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Title: Social Life in the Insect World
Author: Fabre, Jean-Henri, 1823-1915
Language: English
As this book started as an ASCII text book there are no pictures available.
*** Start of this LibraryBlog Digital Book "Social Life in the Insect World" ***
SOCIAL LIFE
IN THE INSECT WORLD
BY
J. H. FABRE
TRANSLATED BY
BERNARD MIALL
WITH 14 ILLUSTRATIONS
LONDON
T. FISHER UNWIN, LTD.
ADELPHI TERRACE
_First Edition_ 1911
_Second Impression_ 1912
_Third Impression_ 1912
_Fourth Impression_ 1913
_Fifth Impression_ 1913
_Sixth Impression_ 1915
_Seventh Impression_ 1916
_Eighth Impression_ 1916
_Ninth Impression_ 1917
_Tenth Impression_ 1918
_Eleventh Impression_ 1918
_Twelfth Impression_ 1919
(_All rights reserved_)
[Illustration: 1. THE MANTIS. A DUEL BETWEEN FEMALES.
2. THE MANTIS DEVOURING A CRICKET.
3. THE MANTIS DEVOURING HER MATE.
4. THE MANTIS IN HER ATTITUDE OF PRAYER.
5. THE MANTIS IN HER "SPECTRAL" ATTITUDE.
(See p. 76.)]
CONTENTS
CHAPTER I PAGE
THE FABLE OF THE CIGALE AND THE ANT 1
CHAPTER II
THE CIGALE LEAVES ITS BURROW 17
CHAPTER III
THE SONG OF THE CIGALE 31
CHAPTER IV
THE CIGALE. THE EGGS AND THEIR HATCHING 45
CHAPTER V
THE MANTIS. THE CHASE 68
CHAPTER VI
THE MANTIS. COURTSHIP 79
CHAPTER VII
THE MANTIS. THE NEST 86
CHAPTER VIII
THE GOLDEN GARDENER. ITS NUTRIMENT 102
CHAPTER IX
THE GOLDEN GARDENER. COURTSHIP 111
CHAPTER X
THE FIELD CRICKET 120
CHAPTER XI
THE ITALIAN CRICKET 130
CHAPTER XII
THE SISYPHUS BEETLE. THE INSTINCT OF PATERNITY 136
CHAPTER XIII
A BEE-HUNTER: THE _PHILANTHUS AVIPORUS_ 150
CHAPTER XIV
THE GREAT PEACOCK, OR EMPEROR MOTH 179
CHAPTER XV
THE OAK EGGAR, OR BANDED MONK 202
CHAPTER XVI
A TRUFFLE-HUNTER: THE _BOLBOCERAS GALLICUS_ 217
CHAPTER XVII
THE ELEPHANT-BEETLE 238
CHAPTER XVIII
THE PEA-WEEVIL 258
CHAPTER XIX
AN INVADER: THE HARICOT-WEEVIL 282
CHAPTER XX
THE GREY LOCUST 300
CHAPTER XXI
THE PINE-CHAFER 317
ILLUSTRATIONS
THE MANTIS: A DUEL BETWEEN FEMALES; DEVOURING
A CRICKET; DEVOURING HER MATE; IN HER ATTITUDE
OF PRAYER; IN HER "SPECTRAL" ATTITUDE _Frontispiece_
DURING THE DROUGHTS OF SUMMER THIRSTING INSECTS,
AND NOTABLY THE ANT, FLOCK TO THE DRINKING-PLACES
OF THE CIGALE 8
THE CIGALE AND THE EMPTY PUPA-SKIN 28
THE ADULT CIGALE, FROM BELOW. THE CIGALE OF
THE FLOWERING ASH, MALE AND FEMALE 36
THE CIGALE LAYING HER EGGS. THE GREEN GRASSHOPPER,
THE FALSE CIGALE OF THE NORTH,
DEVOURING THE TRUE CIGALE, A DWELLER IN
THE SOUTH 48
THE NEST OF THE PRAYING MANTIS; TRANSVERSE SECTION
OF THE SAME; NEST OF EMPUSA PAUPERATA;
TRANSVERSE SECTION OF THE SAME; VERTICAL
SECTION OF THE SAME; NEST OF THE GREY MANTIS;
SCHEFFER'S SISYPHUS (see Chap. XII.); PELLET OF
THE SISYPHUS; PELLET OF THE SISYPHUS, WITH
DEJECTA OF THE LARVA FORCED THROUGH THE
WALLS 88
THE MANTIS DEVOURING THE MALE IN THE ACT OF
MATING; THE MANTIS COMPLETING HER NEST;
GOLDEN SCARABÆI CUTTING UP A LOB-WORM 90
THE GOLDEN GARDENER: THE MATING SEASON OVER,
THE MALES ARE EVISCERATED BY THE FEMALES 114
THE FIELD-CRICKET: A DUEL BETWEEN RIVALS; THE
DEFEATED RIVAL RETIRES, INSULTED BY THE
VICTOR 124
THE ITALIAN CRICKET 132
THE GREAT PEACOCK OR EMPEROR MOTH 180
THE GREAT PEACOCK MOTH. THE PILGRIMS DIVERTED
BY THE LIGHT OF A LAMP 196
THE GREY LOCUST; THE NERVATURES OF THE WING;
THE BALANINUS FALLEN A VICTIM TO THE LENGTH
OF HER PROBOSCIS 244
THE PINE-CHAFER (_MELOLONTHA FULLO_) 318
SOCIAL LIFE IN THE INSECT WORLD
CHAPTER I
THE FABLE OF THE CIGALE AND THE ANT
Fame is the daughter of Legend. In the world of creatures, as in the
world of men, the story precedes and outlives history. There are many
instances of the fact that if an insect attract our attention for this
reason or that, it is given a place in those legends of the people whose
last care is truth.
For example, who is there that does not, at least by hearsay, know the
Cigale? Where in the entomological world shall we find a more famous
reputation? Her fame as an impassioned singer, careless of the future,
was the subject of our earliest lessons in repetition. In short, easily
remembered lines of verse, we learned how she was destitute when the
winter winds arrived, and how she went begging for food to the Ant, her
neighbour. A poor welcome she received, the would-be borrower!--a
welcome that has become proverbial, and her chief title to celebrity.
The petty malice of the two short lines--
Vous chantiez! j'en suis bien aise,
Eh bien, dansez maintenant!
has done more to immortalise the insect than her skill as a musician.
"You sang! I am very glad to hear it! Now you can dance!" The words
lodge in the childish memory, never to be forgotten. To most
Englishmen--to most Frenchmen even--the song of the Cigale is unknown,
for she dwells in the country of the olive-tree; but we all know of the
treatment she received at the hands of the Ant. On such trifles does
Fame depend! A legend of very dubious value, its moral as bad as its
natural history; a nurse's tale whose only merit is its brevity; such is
the basis of a reputation which will survive the wreck of centuries no
less surely than the tale of Puss-in-Boots and of Little Red
Riding-Hood.
The child is the best guardian of tradition, the great conservative.
Custom and tradition become indestructible when confided to the archives
of his memory. To the child we owe the celebrity of the Cigale, of whose
misfortunes he has babbled during his first lessons in recitation. It is
he who will preserve for future generations the absurd nonsense of which
the body of the fable is constructed; the Cigale will always be hungry
when the cold comes, although there were never Cigales in winter; she
will always beg alms in the shape of a few grains of wheat, a diet
absolutely incompatible with her delicate capillary "tongue"; and in
desperation she will hunt for flies and grubs, although she never eats.
Whom shall we hold responsible for these strange mistakes? La Fontaine,
who in most of his fables charms us with his exquisite fineness of
observation, has here been ill-inspired. His earlier subjects he knew
down to the ground: the Fox, the Wolf, the Cat, the Stag, the Crow, the
Rat, the Ferret, and so many others, whose actions and manners he
describes with a delightful precision of detail. These are inhabitants
of his own country; neighbours, fellow-parishioners. Their life, private
and public, is lived under his eyes; but the Cigale is a stranger to the
haunts of Jack Rabbit. La Fontaine had never seen nor heard her. For him
the celebrated songstress was certainly a grasshopper.
Grandville, whose pencil rivals the author's pen, has fallen into the
same error. In his illustration to the fable we see the Ant dressed like
a busy housewife. On her threshold, beside her full sacks of wheat, she
disdainfully turns her back upon the would-be borrower, who holds out
her claw--pardon, her hand. With a wide coachman's hat, a guitar under
her arm, and a skirt wrapped about her knees by the gale, there stands
the second personage of the fable, the perfect portrait of a
grasshopper. Grandville knew no more than La Fontaine of the true
Cigale; he has beautifully expressed the general confusion.
But La Fontaine, in this abbreviated history, is only the echo of
another fabulist. The legend of the Cigale and the cold welcome of the
Ant is as old as selfishness: as old as the world. The children of
Athens, going to school with their baskets of rush-work stuffed with
figs and olives, were already repeating the story under their breath, as
a lesson to be repeated to the teacher. "In winter," they used to say,
"the Ants were putting their damp food to dry in the sun. There came a
starving Cigale to beg from them. She begged for a few grains. The
greedy misers replied: 'You sang in the summer, now dance in the
winter.'" This, although somewhat more arid, is precisely La Fontaine's
story, and is contrary to the facts.
Yet the story comes to us from Greece, which is, like the South of
France, the home of the olive-tree and the Cigale. Was Æsop really its
author, as tradition would have it? It is doubtful, and by no means a
matter of importance; at all events, the author was a Greek, and a
compatriot of the Cigale, which must have been perfectly familiar to
him. There is not a single peasant in my village so blind as to be
unaware of the total absence of Cigales in winter; and every tiller of
the soil, every gardener, is familiar with the first phase of the
insect, the larva, which his spade is perpetually discovering when he
banks up the olives at the approach of the cold weather, and he knows,
having seen it a thousand times by the edge of the country paths, how in
summer this larva issues from the earth from a little round well of its
own making; how it climbs a twig or a stem of grass, turns upon its
back, climbs out of its skin, drier now than parchment, and becomes the
Cigale; a creature of a fresh grass-green colour which is rapidly
replaced by brown.
We cannot suppose that the Greek peasant was so much less intelligent
than the Provençal that he can have failed to see what the least
observant must have noticed. He knew what my rustic neighbours know so
well. The scribe, whoever he may have been, who was responsible for the
fable was in the best possible circumstances for correct knowledge of
the subject. Whence, then, arose the errors of his tale?
Less excusably than La Fontaine, the Greek fabulist wrote of the Cigale
of the books, instead of interrogating the living Cigale, whose cymbals
were resounding on every side; careless of the real, he followed
tradition. He himself echoed a more ancient narrative; he repeated some
legend that had reached him from India, the venerable mother of
civilisations. We do not know precisely what story the reed-pen of the
Hindoo may have confided to writing, in order to show the perils of a
life without foresight; but it is probable that the little animal drama
was nearer the truth than the conversation between the Cigale and the
Ant. India, the friend of animals, was incapable of such a mistake.
Everything seems to suggest that the principal personage of the original
fable was not the Cigale of the Midi, but some other creature, an insect
if you will, whose manners corresponded to the adopted text.
Imported into Greece, after long centuries during which, on the banks of
the Indus, it made the wise reflect and the children laugh, the ancient
anecdote, perhaps as old as the first piece of advice that a father of a
family ever gave in respect of economy, transmitted more or less
faithfully from one memory to another, must have suffered alteration in
its details, as is the fate of all such legends, which the passage of
time adapts to the circumstance of time and place.
The Greek, not finding in his country the insect of which the Hindoo
spoke, introduced the Cigale, as in Paris, the modern Athens, the Cigale
has been replaced by the Grasshopper. The mistake was made; henceforth
indelible. Entrusted as it is to the memory of childhood, error will
prevail against the truth that lies before our eyes.
Let us seek to rehabilitate the songstress so calumniated by the fable.
She is, I grant you, an importunate neighbour. Every summer she takes up
her station in hundreds before my door, attracted thither by the verdure
of two great plane-trees; and there, from sunrise to sunset, she hammers
on my brain with her strident symphony. With this deafening concert
thought is impossible; the mind is in a whirl, is seized with vertigo,
unable to concentrate itself. If I have not profited by the early
morning hours the day is lost.
Ah! Creature possessed, the plague of my dwelling, which I hoped would
be so peaceful!--the Athenians, they say, used to hang you up in a
little cage, the better to enjoy your song. One were well enough, during
the drowsiness of digestion; but hundreds, roaring all at once,
assaulting the hearing until thought recoils--this indeed is torture!
You put forward, as excuse, your rights as the first occupant. Before my
arrival the two plane-trees were yours without reserve; it is I who have
intruded, have thrust myself into their shade. I confess it: yet muffle
your cymbals, moderate your arpeggi, for the sake of your historian! The
truth rejects what the fabulist tells us as an absurd invention. That
there are sometimes dealings between the Cigale and the Ant is perfectly
correct; but these dealings are the reverse of those described in the
fable. They depend not upon the initiative of the former; for the Cigale
never required the help of others in order to make her living: on the
contrary, they are due to the Ant, the greedy exploiter of others, who
fills her granaries with every edible she can find. At no time does the
Cigale plead starvation at the doors of the ant-hills, faithfully
promising a return of principal and interest; the Ant on the contrary,
harassed by drought, begs of the songstress. Begs, do I say! Borrowing
and repayment are no part of the manners of this land-pirate. She
exploits the Cigale; she impudently robs her. Let us consider this
theft; a curious point of history as yet unknown.
In July, during the stifling hours of the afternoon, when the insect
peoples, frantic with drought, wander hither and thither, vainly seeking
to quench their thirst at the faded, exhausted flowers, the Cigale makes
light of the general aridity. With her rostrum, a delicate augur, she
broaches a cask of her inexhaustible store. Crouching, always singing,
on the twig of a suitable shrub or bush, she perforates the firm, glossy
rind, distended by the sap which the sun has matured. Plunging her
proboscis into the bung-hole, she drinks deliciously, motionless, and
wrapt in meditation, abandoned to the charms of syrup and of song.
Let us watch her awhile. Perhaps we shall witness unlooked-for
wretchedness and want. For there are many thirsty creatures wandering
hither and thither; and at last they discover the Cigale's private well,
betrayed by the oozing sap upon the brink. They gather round it, at
first with a certain amount of constraint, confining themselves to
lapping the extravasated liquor. I have seen, crowding around the
honeyed perforation, wasps, flies, earwigs, Sphinx-moths, Pompilidæ,
rose-chafers, and, above all, ants.
The smallest, in order to reach the well, slip under the belly of the
Cigale, who kindly raises herself on her claws, leaving room for the
importunate ones to pass. The larger, stamping with impatience, quickly
snatch a mouthful, withdraw, take a turn on the neighbouring twigs, and
then return, this time more enterprising. Envy grows keener; those who
but now were cautious become turbulent and aggressive, and would
willingly drive from the spring the well-sinker who has caused it to
flow.
In this crowd of brigands the most aggressive are the ants. I have seen
them nibbling the ends of the Cigale's claws; I have caught them tugging
the ends of her wings, climbing on her back, tickling her antennæ. One
audacious individual so far forgot himself under my eyes as to seize her
proboscis, endeavouring to extract it from the well!
Thus hustled by these dwarfs, and at the end of her patience, the
giantess finally abandons the well. She flies away, throwing a jet of
liquid excrement over her tormentors as she goes. But what cares the Ant
for this expression of sovereign contempt? She is left in possession of
the spring--only too soon exhausted when the pump is removed that made
it flow. There is little left, but that little is sweet. So much to the
good; she can wait for another drink, attained in the same manner, as
soon as the occasion presents itself.
[Illustration: DURING THE DROUGHTS OF SUMMER THIRSTING INSECTS, AND
NOTABLY THE ANT, FLOCK TO THE DRINKING-PLACES OF THE CIGALE.]
As we see, reality completely reverses the action described by the
fable. The shameless beggar, who does not hesitate at theft, is the Ant;
the industrious worker, willingly sharing her goods with the suffering,
is the Cigale. Yet another detail, and the reversal of the fable is
further emphasised. After five or six weeks of gaiety, the songstress
falls from the tree, exhausted by the fever of life. The sun shrivels
her body; the feet of the passers-by crush it. A bandit always in search
of booty, the Ant discovers the remains. She divides the rich find,
dissects it, and cuts it up into tiny fragments, which go to swell her
stock of provisions. It is not uncommon to see a dying Cigale, whose
wings are still trembling in the dust, drawn and quartered by a gang of
knackers. Her body is black with them. After this instance of
cannibalism the truth of the relations between the two insects is
obvious.
Antiquity held the Cigale in high esteem. The Greek Béranger, Anacreon,
devoted an ode to her, in which his praise of her is singularly
exaggerated. "Thou art almost like unto the Gods," he says. The reasons
which he has given for this apotheosis are none of the best. They
consist in these three privileges: [Greek: gêgenês, apathês,
hanaimosarke]; born of the earth, insensible to pain, bloodless. We will
not reproach the poet for these mistakes; they were then generally
believed, and were perpetuated long afterwards, until the exploring eye
of scientific observation was directed upon them. And in minor poetry,
whose principal merit lies in rhythm and harmony, we must not look at
things too closely.
Even in our days, the Provençal poets, who know the Cigale as Anacreon
never did, are scarcely more careful of the truth in celebrating the
insect which they have taken for their emblem. A friend of mine, an
eager observer and a scrupulous realist, does not deserve this reproach.
He gives me permission to take from his pigeon-holes the following
Provençal poem, in which the relations between the Cigale and the Ant
are expounded with all the rigour of science. I leave to him the
responsibility for his poetic images and his moral reflections, blossoms
unknown to my naturalist's garden; but I can swear to the truth of all
he says, for it corresponds with what I see each summer on the
lilac-trees of my garden.
LA CIGALO E LA FOURNIGO.
I.
Jour de Dièu, queto caud! Bèu tèms pèr la Cigalo,
Que, trefoulido, se regalo
D'uno raisso de fio; bèu tèms per la meissoun.
Dins lis erso d'or, lou segaire,
Ren plega, pitre au vent, rustico e canto gaire;
Dins soun gousiè, la set estranglo la cansoun.
Tèms benesi pèr tu. Dounc, ardit! cigaleto,
Fai-lei brusi, ti chimbaleto,
E brandusso lou ventre à creba ti mirau.
L'Ome enterin mando le daio,
Que vai balin-balan de longo e que dardaio
L'ulau de soun acié sus li rous espigau.
Plèn d'aigo pèr la péiro e tampouna d'erbiho
Lou coufié sus l'anco pendiho.
Si la péiro es au frès dins soun estui de bos,
E se de longo es abèurado,
L'Ome barbelo au fio d'aqueli souleiado
Que fan bouli de fes la mesoulo dis os.
Tu, Cigalo, as un biais pèr la set: dins la rusco
Tendro e jutouso d'uno busco,
L'aguio de toun bè cabusso e cavo un pous.
Lou siro monto pèr la draio.
T'amourres à la fon melicouso que raio,
E dou sourgènt sucra bèves lou teta-dous.
Mai pas toujour en pas. Oh! que nàni; de laire,
Vesin, vesino o barrulaire,
T'an vist cava lou pous. An set; vènon, doulènt,
Te prène un degout pèr si tasso.
Mesfiso-te, ma bello: aqueli curo-biasso,
Umble d'abord, soun lèu de gusas insoulènt.
Quiston un chicouloun di rèn, pièi de ti resto
Soun plus countènt, ausson la testo
E volon tout: L'auran. Sis arpioun en rastèu
Te gatihoun lou bout de l'alo.
Sus tu larjo esquinasso es un mounto-davalo;
T'aganton pèr lou bè, li bano, lis artèu;
Tiron d'eici, d'eilà. L'impaciènci te gagno.
Pst! pst! d'un giscle de pissagno
Aspèrges l'assemblado e quites lou ramèu.
T'en vas bèn liuen de la racaio,
Que t'a rauba lou pous, e ris, e se gougaio,
E se lipo li brego enviscado de mèu.
Or d'aqueli boumian abèura sens fatigo,
Lou mai tihous es la fournigo.
Mousco, cabrian, guespo e tavan embana,
Espeloufi de touto meno,
Costo-en-long qu'à toun pous lou soulcias ameno,
N'an pas soun testardige à te faire enana.
Pèr l'esquicha l'artèu, te coutiga lou mourre,
Te pessuga lou nas, pèr courre
A l'oumbro du toun ventre, osco! degun la vau.
Lou marrit-pèu prend pèr escalo
Uno patto e te monto, ardido, sus lis alo,
E s'espasso, insoulènto, e vai d'amont, d'avau.
II.
Aro veici qu'es pas de crèire.
Ancian tèms, nous dison li rèire,
Un jour d'ivèr; la fam te prenguè. Lou front bas
E d'escoundoun anères vèire,
Dins si grand magasin, la fournigo, eilàbas.
L'endrudido au soulèu secavo,
Avans de lis escoundre en cavo,
Si blad qu'aviè mousi l'eigagno de la niue.
Quand èron lest lis ensacavo.
Tu survènes alor, emé de plour is iue.
Iè disés: "Fai bèn fre; l'aurasso
D'un caire à l'autre me tirasso
Avanido de fam. A toun riche mouloun
Leisso-me prène pèr ma biasso.
Te lou rendrai segur au bèu tèms di meloun.
"Presto-me un pan de gran." Mai, bouto,
Se cresès que l'autro t'escouto,
T'enganes. Di gros sa, rèn de rèn sara tièu.
"Vai-t'en plus liuen rascla de bouto;
Crebo de fam l'ivèr, tu que cantes l'estièu."
Ansin charro la fablo antico
Pèr nous counséia la pratico
Di sarro-piastro, urous de nousa li cordoun
De si bourso.--Que la coulico
Rousiguè la tripaio en aqueli coudoun!
Me fai susa, lou fabulisto,
Quand dis que l'ivèr vas en quisto
De mousco, verme, gran, tu que manges jamai.
De blad! Que n'en fariès, ma fisto!
As ta fon melicouso e demandes rèn mai.
Que t'enchau l'ivèr! Ta famiho
A la sousto en terro soumiho,
Et tu dormes la som que n'a ges de revèi;
Toun cadabre toumbo en douliho.
Un jour, en tafurant, la fournigo lou véi,
De tu magro péu dessecado
La marriasso fai becado;
Te curo lou perus, te chapouto à moucèu,
T'encafourno pèr car-salado,
Requisto prouvisioun, l'ivèr, en tèms de neu.
III.
Vaqui l'istori veritablo
Bèn liuen dôu conte de la fablo.
Que n'en pensas, canèu de sort!
--O rammaissaire de dardeno
Det croucu, boumbudo bedeno
Que gouvernas lou mounde emé lou coffre-fort,
Fasès courre lou bru, canaio,
Que l'artisto jamai travaio
E dèu pati, lou bedigas.
Teisas-vous dounc: quand di lambrusco
La Cigalo a cava la rusco,
Raubas soun bèure, e pièi, morto, la rousigas.
So speaks my friend in the expressive Provençal idiom, rehabilitating
the creature so libelled by the fabulist.
Translated with a little necessary freedom, the English of it is as
follows:--
I.
Fine weather for the Cigale! God, what heat!
Half drunken with her joy, she feasts
In a hail of fire. Pays for the harvest meet;
A golden sea the reaper breasts,
Loins bent, throat bare; silent, he labours long,
For thirst within his throat has stilled the song.
A blessed time for thee, little Cigale.
Thy little cymbals shake and sound,
Shake, shake thy stomach till thy mirrors fall!
Man meanwhile swings his scythe around;
Continually back and forth it veers,
Flashing its steel amidst the ruddy ears.
Grass-plugged, with water for the grinder full,
A flask is hung upon his hip;
The stone within its wooden trough is cool,
Free all the day to sip and sip;
But man is gasping in the fiery sun,
That makes his very marrow melt and run.
Thou, Cigale, hast a cure for thirst: the bark,
Tender and juicy, of the bough.
Thy beak, a very needle, stabs it. Mark
The narrow passage welling now;
The sugared stream is flowing, thee beside,
Who drinkest of the flood, the honeyed tide.
Not in peace always; nay, for thieves arrive,
Neighbours and wives, or wanderers vile;
They saw thee sink the well, and ill they thrive
Thirsting; they seek to drink awhile;
Beauty, beware! the wallet-snatcher's face,
Humble at first, grows insolent apace.
They seek the merest drop; thy leavings take;
Soon discontent, their heads they toss;
They crave for all, and all will have. They rake
Their claws thy folded wings across;
Thy back a mountain, up and down each goes;
They seize thee by the beak, the horns, the toes.
This way and that they pull. Impatient thou:
Pst! Pst! a jet of nauseous taste
O'er the assembly sprinklest. Leave the bough
And fly the rascals thus disgraced,
Who stole thy well, and with malicious pleasure
Now lick their honey'd lips, and feed at leisure.
See these Bohemians without labour fed!
The ant the worst of all the crew--
Fly, drone, wasp, beetle too with horned head,
All of them sharpers thro' and thro',
Idlers the sun drew to thy well apace--
None more than she was eager for thy place,
More apt thy face to tickle, toe to tread,
Or nose to pinch, and then to run
Under the shade thine ample belly spread;
Or climb thy leg for ladder; sun
Herself audacious on thy wings, and go
Most insolently o'er thee to and fro.
II.
Now comes a tale that no one should believe.
In other times, the ancients say,
The winter came, and hunger made thee grieve.
Thou didst in secret see one day
The ant below the ground her treasure store away.
The wealthy ant was drying in the sun
Her corn the dew had wet by night,
Ere storing it again; and one by one
She filled her sacks as it dried aright.
Thou camest then, and tears bedimmed thy sight,
Saying: "'Tis very cold; the bitter bise
Blows me this way and that to-day.
I die of hunger. Of your riches please
Fill me my bag, and I'll repay,
When summer and its melons come this way.
"Lend me a little corn." Go to, go to!
Think you the ant will lend an ear?
You are deceived. Great sacks, but nought for you!
"Be off, and scrape some barrel clear!
You sing of summer: starve, for winter's here!"
'Tis thus the ancient fable sings
To teach us all the prudence ripe
Of farthing-snatchers, glad to knot the string
That tie their purses. May the gripe
Of colic twist the guts of all such tripe!
He angers me, this fable-teller does,
Saying in winter thou dost seek
Flies, grubs, corn--thou dost never eat like us!
--Corn! Couldst thou eat it, with thy beak?
Thou hast thy fountain with its honey'd reek.
To thee what matters winter? Underground
Slumber thy children, sheltered; thou
The sleep that knows no waking sleepest sound.
Thy body, fallen from the bough,
Crumbles; the questing ant has found thee now.
The wicked ant of thy poor withered hide
A banquet makes; in little bits
She cuts thee up, and empties thine inside,
And stores thee where in wealth she sits:
Choice diet when the winter numbs the wits.
III.
Here is the tale related duly,
And little resembling the fable, truly!
Hoarders of farthings, I know, deuce take it.
It isn't the story as you would make it!
Crook-fingers, big-bellies, what do you say,
Who govern the world with the cash-box--hey?
You have spread the story, with shrug and smirk,
That the artist ne'er does a stroke of work;
And so let him suffer, the imbecile!
Be you silent! 'Tis you, I think,
When the Cigale pierces the vine to drink,
Drive her away, her drink to steal;
And when she is dead--you make your meal!
CHAPTER II
THE CIGALE LEAVES ITS BURROW
The first Cigales appear about the summer solstice. Along the beaten
paths, calcined by the sun, hardened by the passage of frequent feet, we
see little circular orifices almost large enough to admit the thumb.
These are the holes by which the larvæ of the Cigale have come up from
the depths to undergo metamorphosis. We see them more or less
everywhere, except in fields where the soil has been disturbed by
ploughing. Their usual position is in the driest and hottest situations,
especially by the sides of roads or the borders of footpaths. Powerfully
equipped for the purpose, able at need to pierce the turf or sun-dried
clay, the larva, upon leaving the earth, seems to prefer the hardest
spots.
A garden alley, converted into a little Arabia Petræa by reflection from
a wall facing the south, abounds in such holes. During the last days of
June I have made an examination of these recently abandoned pits. The
soil is so compact that I needed a pick to tackle it.
The orifices are round, and close upon an inch in diameter. There is
absolutely no debris round them; no earth thrown up from within. This is
always the case; the holes of the Cigales are never surrounded by
dumping-heaps, as are the burrows of the Geotrupes, another notable
excavator. The way in which the work is done is responsible for this
difference. The dung-beetle works from without inwards; she begins to
dig at the mouth of the burrow, and afterwards re-ascends and
accumulates the excavated material on the surface. The larva of the
Cigale, on the contrary, works outward from within, upward from below;
it opens the door of exit at the last moment, so that it is not free for
the discharge of excavated material until the work is done. The first
enters and raises a little rubbish-heap at the threshold of her burrow;
the second emerges, and cannot, while working, pile up its rubbish on a
threshold which as yet has no existence.
The burrow of the Cigale descends about fifteen inches. It is
cylindrical, slightly twisted, according to the exigencies of the soil,
and always approaches the vertical, or the direction of the shortest
passage. It is perfectly free along its entire length. We shall search
in vain for the rubbish which such an excavation must apparently
produce; we shall find nothing of the sort. The burrow terminates in a
cul-de-sac, in a fairly roomy chamber with unbroken walls, which shows
not the least vestige of communication with any other burrow or
prolongation of the shaft.
Taking its length and diameter into account, we find the excavation has
a total volume of about twelve cubic inches. What becomes of the earth
which is removed?
Sunk in a very dry, crumbling soil, we should expect the shaft and the
chamber at the bottom to have soft, powdery walls, subject to petty
landslips, if no work were done but that of excavation. On the contrary,
the walls are neatly daubed, plastered with a sort of clay-like mortar.
They are not precisely smooth, indeed they are distinctly rough; but
their irregularities are covered with a layer of plaster, and the
crumbling material, soaked in some glutinous liquid and dried, is held
firmly in place.
The larva can climb up and down, ascend nearly to the surface, and go
down into its chamber of refuge, without bringing down, with his claws,
the continual falls of material which would block the burrow, make
ascent a matter of difficulty, and retreat impossible. The miner shores
up his galleries with uprights and cross-timbers; the builder of
underground railways supports the sides and roofs of his tunnels with a
lining of brick or masonry or segments of iron tube; the larva of the
Cigale, no less prudent an engineer, plasters the walls of its burrow
with cement, so that the passage is always free and ready for use.
If I surprise the creature just as it is emerging from the soil in order
to gain a neighbouring bough and there undergo transformation, I see it
immediately make a prudent retreat, descending to the bottom of its
burrow without the slightest difficulty--a proof that even when about to
be abandoned for ever the refuge is not encumbered with rubbish.
The ascending shaft is not a hurried piece of work, scamped by a
creature impatient to reach the sunlight. It is a true dwelling, in
which the larva may make a long stay. The plastered walls betray as
much. Such precautions would be useless in the case of a simple exit
abandoned as soon as made. We cannot doubt that the burrow is a kind of
meteorological observatory, and that its inhabitant takes note of the
weather without. Buried underground at a depth of twelve or fifteen
inches, the larva, when ripe for escape, could hardly judge whether the
meteorological conditions were favourable. The subterranean climate
varies too little, changes too slowly, and would not afford it the
precise information required for the most important action of its
life--the escape into the sunshine at the time of metamorphosis.
Patiently, for weeks, perhaps for months, it digs, clears, and
strengthens a vertical shaft, leaving only a layer of earth a finger's
breadth in thickness to isolate it from the outer world. At the bottom
it prepares a carefully built recess. This is its refuge, its place of
waiting, where it reposes in peace if its observations decide it to
postpone its final departure. At the least sign of fine weather it
climbs to the top of its burrow, sounds the outer world through the thin
layer of earth which covers the shaft, and informs itself of the
temperature and humidity of the outer air.
If things are not going well--if there are threats of a flood or the
dreaded _bise_--events of mortal gravity when the delicate insect issues
from its cerements--the prudent creature re-descends to the bottom of
its burrow for a longer wait. If, on the contrary, the state of the
atmosphere is favourable, the roof is broken through by a few strokes of
its claws, and the larva emerges from its tunnel.
Everything seems to prove that the burrow of the Cigale is a
waiting-room, a meteorological station, in which the larva makes a
prolonged stay; sometimes hoisting itself to the neighbourhood of the
surface in order to ascertain the external climate; sometimes retiring
to the depths the better to shelter itself. This explains the chamber
at the base of the shaft, and the necessity of a cement to hold the
walls together, for otherwise the creature's continual comings and
goings would result in a landslip.
A matter less easy of explanation is the complete disappearance of the
material which originally filled the excavated space. Where are the
twelve cubic inches of earth that represent the average volume of the
original contents of the shaft? There is not a trace of this material
outside, nor inside either. And how, in a soil as dry as a cinder, is
the plaster made with which the walls are covered?
Larvæ which burrow in wood, such as those of Capricornis and Buprestes,
will apparently answer our first question. They make their way through
the substance of a tree-trunk, boring their galleries by the simple
method of eating the material in front of them. Detached by their
mandibles, fragment by fragment, the material is digested. It passes
from end to end through the body of the pioneer, yields during its
passage its meagre nutritive principles, and accumulates behind it,
obstructing the passage, by which the larva will never return. The work
of extreme division, effected partly by the mandibles and partly by the
stomach, makes the digested material more compact than the intact wood,
from which it follows that there is always a little free space at the
head of the gallery, in which the caterpillar works and lives; it is not
of any great length, but just suffices for the movements of the
prisoner.
Must not the larva of the Cigale bore its passage in some such fashion?
I do not mean that the results of excavation pass through its body--for
earth, even the softest mould, could form no possible part of its diet.
But is not the material detached simply thrust back behind the excavator
as the work progresses?
The Cigale passes four years under ground. This long life is not spent,
of course, at the bottom of the well I have just described; that is
merely a resting-place preparatory to its appearance on the face of the
earth. The larva comes from elsewhere; doubtless from a considerable
distance. It is a vagabond, roaming from one root to another and
implanting its rostrum. When it moves, either to flee from the upper
layers of the soil, which in winter become too cold, or to install
itself upon a more juicy root, it makes a road by rejecting behind it
the material broken up by the teeth of its picks. That this is its
method is incontestable.
As with the larvæ of Capricornis and Buprestes, it is enough for the
traveller to have around it the small amount of free space necessitated
by its movements. Moist, soft, and easily compressible soil is to the
larva of the Cigale what digested wood-pulp is to the others. It is
compressed without difficulty, and so leaves a vacant space.
The difficulty is that sometimes the burrow of exit from the
waiting-place is driven through a very arid soil, which is extremely
refractory to compression so long as it retains its aridity. That the
larva, when commencing the excavation of its burrow, has already thrust
part of the detached material into a previously made gallery, now filled
up and disappeared, is probable enough, although nothing in the actual
condition of things goes to support the theory; but if we consider the
capacity of the shaft and the extreme difficulty of making room for such
a volume of debris, we feel dubious once more; for to hide such a
quantity of earth a considerable empty space would be necessary, which
could only be obtained by the disposal of more debris. Thus we are
caught in a vicious circle. The mere packing of the powdered earth
rejected behind the excavator would not account for so large a void. The
Cigale must have a special method of disposing of the waste earth. Let
us see if we can discover the secret.
Let us examine a larva at the moment of emerging from the soil. It is
almost always more or less smeared with mud, sometimes dried, sometimes
moist. The implements of excavation, the claws of the fore-feet, have
their points covered by little globules of mortar; the others bear
leggings of mud; the back is spotted with clay. One is reminded of a
scavenger who has been scooping up mud all day. This condition is the
more striking in that the insect comes from an absolutely dry soil. We
should expect to see it dusty; we find it muddy.
One more step, and the problem of the well is solved. I exhume a larva
which is working at its gallery of exit. Chance postpones this piece of
luck, which I cannot expect to achieve at once, since nothing on the
surface guides my search. But at last I am rewarded, and the larva is
just beginning its excavation. An inch of tunnel, free of all waste or
rubbish, and at the bottom the chamber, the place of rest; so far has
the work proceeded. And the worker--in what condition is it? Let us see.
The larva is much paler in colour than those which I have caught as they
emerged. The large eyes in particular are whitish, cloudy, blurred, and
apparently blind. What would be the use of sight underground? The eyes
of the larvæ leaving their burrows are black and shining, and evidently
capable of sight. When it issues into the sunlight the future Cigale
must find, often at some distance from its burrow, a suitable twig from
which to hang during its metamorphosis, so that sight is obviously of
the greatest utility. The maturity of the eyes, attained during the time
of preparation before deliverance, proves that the larva, far from
boring its tunnel in haste, has spent a long time labouring at it.
What else do we notice? The blind, pale larva is far more voluminous
than in the mature state; it is swollen with liquid as though it had
dropsy. Taken in the fingers, a limpid serum oozes from the hinder part
of the body, which moistens the whole surface. Is this fluid, evacuated
by the intestine, a product of urinary secretion--simply the contents of
a stomach nourished entirely upon sap? I will not attempt to decide, but
for convenience will content myself with calling it urine.
Well, this fountain of urine is the key to the enigma. As it digs and
advances the larva waters the powdery debris and converts it into a
paste, which is immediately applied to the walls by the pressure of the
abdomen. Aridity is followed by plasticity. The mud thus obtained
penetrates the interstices of the rough soil; the more liquid portion
enters the substance of the soil by infiltration; the remainder becomes
tightly packed and fills up the inequalities of the walls. Thus the
insect obtains an empty tunnel, with no loose waste, as all the loosened
soil is utilised on the spot, converted into a mortar which is more
compact and homogeneous than the soil through which the shaft is
driven.
Thus the larva works in the midst of a coating of mud, which is the
cause of its dirtiness, so astonishing when we see it issue from an
excessively dry soil. The perfect insect, although henceforth liberated
from the work of a sapper and miner, does not entirely abandon the use
of urine as a weapon, employing it as a means of defence. Too closely
observed it throws a jet of liquid upon the importunate enemy and flies
away. In both its forms the Cigale, in spite of its dry temperament, is
a famous irrigator.
Dropsical as it is, the larva cannot contain sufficient liquid to
moisten and convert into easily compressible mud the long column of
earth which must be removed from the burrow. The reservoir becomes
exhausted, and the provision must be renewed. Where, and how? I think I
can answer the question.
The few burrows uncovered along their entirety, with the meticulous care
such a task demands, have revealed at the bottom, encrusted in the wall
of the terminal chamber, a living root, sometimes of the thickness of a
pencil, sometimes no bigger than a straw. The visible portion of this
root is only a fraction of an inch in length; the rest is hidden by the
surrounding earth. Is the presence of this source of sap fortuitous? Or
is it the result of deliberate choice on the part of the larva? I
incline towards the second alternative, so repeatedly was the presence
of a root verified, at least when my search was skilfully conducted.
Yes, the Cigale, digging its chamber, the nucleus of the future shaft,
seeks out the immediate neighbourhood of a small living root; it lays
bare a certain portion, which forms part of the wall, without
projecting. This living spot in the wall is the fountain where the
supply of moisture is renewed. When its reservoir is exhausted by the
conversion of dry dust into mud the miner descends to its chamber,
thrusts its proboscis into the root, and drinks deep from the vat built
into the wall. Its organs well filled, it re-ascends. It resumes work,
damping the hard soil the better to remove it with its talons, reducing
the debris to mud, in order to pack it tightly around it and obtain a
free passage. In this manner the shaft is driven upwards; logic and the
facts of the case, in the absence of direct observation, justify the
assertion.
If the root were to fail, and the reservoir of the intestine were
exhausted, what would happen? The following experiment will inform us: a
larva is caught as it leaves the earth. I place it at the bottom of a
test-tube, and cover it with a column of dry earth, which is rather
lightly packed. This column is about six inches in height. The larva has
just left an excavation three times as deep, made in soil of the same
kind, but offering a far greater resistance. Buried under this short
column of powdery earth, will it be able to gain the surface? If its
strength hold out the issue should be certain; having but lately made
its way through the hard earth, this obstacle should be easily removed.
But I am not so sure. In removing the stopper which divided it from the
outside world, the larva has expended its final store of liquid. The
cistern is dry, and in default of a living root there is no means of
replenishing it. My suspicions are well founded. For three days the
prisoner struggles desperately, but cannot ascend by so much as an inch.
It is impossible to fix the material removed in the absence of
moisture; as soon as it is thrust aside it slips back again. The labour
has no visible result; it is a labour of Sisyphus, always to be
commenced anew. On the fourth day the creature succumbs.
With the intestines full the result is very different.
I make the same experiment with an insect which is only beginning its
work of liberation. It is swollen with fluid, which oozes from it and
moistens the whole body. Its task is easy; the overlying earth offers
little resistance. A small quantity of liquid from the intestines
converts it into mud; forms a sticky paste which can be thrust aside
with the assurance that it will remain where it is placed. The shaft is
gradually opened; very unevenly, to be sure, and it is almost choked up
behind the insect as it climbs upwards. It seems as though the creature
recognises the impossibility of renewing its store of liquid, and so
economises the little it possesses, using only just so much as is
necessary in order to escape as quickly as possible from surroundings
which are strange to its inherited instincts. This parsimony is so well
judged that the insect gains the surface at the end of twelve days.
The gate of issue is opened and left gaping, like a hole made with an
augur. For some little time the larva wanders about the neighbourhood of
its burrow, seeking an eyrie on some low-growing bush or tuft of thyme,
on a stem of grass or grain, or the twig of a shrub. Once found, it
climbs and firmly clasps its support, the head upwards, while the talons
of the fore feet close with an unyielding grip. The other claws, if the
direction of the twig is convenient, assist in supporting it; otherwise
the claws of the two fore legs will suffice. There follows a moment of
repose, while the supporting limbs stiffen in an unbreakable hold. Then
the thorax splits along the back, and through the fissure the insect
slowly emerges. The whole process lasts perhaps half an hour.
There is the adult insect, freed of its mask, and how different from
what it was but how! The wings are heavy, moist, transparent, with
nervures of a tender green. The thorax is barely clouded with brown. All
the rest of the body is a pale green, whitish in places. Heat and a
prolonged air-bath are necessary to harden and colour the fragile
creature. Some two hours pass without any perceptible change. Hanging to
its deserted shell by the two fore limbs, the Cigale sways to the least
breath of air, still feeble and still green. Finally, the brown colour
appears and rapidly covers the whole body; the change of colour is
completed in half an hour. Fastening upon its chosen twig at nine
o'clock in the morning, the Cigale flies away under my eyes at half-past
twelve.
The empty shell remains, intact except for the fissure in the back;
clasping the twig so firmly that the winds of autumn do not always
succeed in detaching it. For some months yet and even during the winter
you will often find these forsaken skins hanging from the twigs in the
precise attitude assumed by the larva at the moment of metamorphosis.
They are of a horny texture, not unlike dry parchment, and do not
readily decay.
I could gather some wonderful information regarding the Cigale were I to
listen to all that my neighbours, the peasants, tell me. I will give one
instance of rustic natural history.
[Illustration: THE CIGALE AND THE EMPTY PUPA-SKIN.]
Are you afflicted with any kidney trouble, or are you swollen with
dropsy, or have you need of some powerful diuretic? The village
pharmacopoeia is unanimous in recommending the Cigale as a sovereign
remedy. The insects in the adult form are collected in summer. They are
strung into necklaces which are dried in the sun and carefully preserved
in some cupboard or drawer. A good housewife would consider it imprudent
to allow July to pass without threading a few of these insects.
Do you suffer from any nephritic irritation or from stricture? Drink an
infusion of Cigales. Nothing, they say, is more effectual. I must take
this opportunity of thanking the good soul who once upon a time, so I
was afterwards informed, made me drink such a concoction unawares for
the cure of some such trouble; but I still remain incredulous. I have
been greatly struck by the fact that the ancient physician of Anazarbus
used to recommend the same remedy. Dioscorides tells us: _Cicadæ, quae
inassatae manduntur, vesicae doloribus prosunt_. Since the distant days
of this patriarch of _materia medica_ the Provençal peasant has retained
his faith in the remedy revealed to him by the Greeks, who came from
Phocæa with the olive, the fig, and the vine. Only one thing is changed:
Dioscorides advises us to eat the Cigales roasted, but now they are
boiled, and the decoction is administered as medicine. The explanation
which is given of the diuretic properties of the insect is a marvel of
ingenuousness. The Cigale, as every one knows who has tried to catch it,
throws a jet of liquid excrement in one's face as it flies away. It
therefore endows us with its faculties of evacuation. Thus Dioscorides
and his contemporaries must have reasoned; so reasons the peasant of
Provence to-day.
What would you say, worthy neighbours, if you knew of the virtues of the
larva, which is able to mix sufficient mortar with its urine to build a
meteorological station and a shaft connecting with the outer world? Your
powers should equal those of Rabelais' Gargantua, who, seated upon the
towers of Notre Dame, drowned so many thousands of the inquisitive
Parisians.
CHAPTER III
THE SONG OF THE CIGALE
Where I live I can capture five species of Cigale, the two principal
species being the common Cigale and the variety which lives on the
flowering ash. Both of these are widely distributed and are the only
species known to the country folk. The larger of the two is the common
Cigale. Let me briefly describe the mechanism with which it produces its
familiar note.
On the under side of the body of the male, immediately behind the
posterior limbs, are two wide semicircular plates which slightly overlap
one another, the right hand lying over the left hand plate. These are
the shutters, the lids, the dampers of the musical-box. Let us remove
them. To the right and left lie two spacious cavities which are known in
Provençal as the chapels (_li capello_). Together they form the church
(_la glèiso_). Their forward limit is formed by a creamy yellow
membrane, soft and thin; the hinder limit by a dry membrane coloured
like a soap bubble and known in Provençal as the mirror (_mirau_).
The church, the mirrors, and the dampers are commonly regarded as the
organs which produce the cry of the Cigale. Of a singer out of breath
one says that he has broken his mirrors (_a li mirau creba_). The same
phrase is used of a poet without inspiration. Acoustics give the lie to
the popular belief. You may break the mirrors, remove the covers with a
snip of the scissors, and tear the yellow anterior membrane, but these
mutilations do not silence the song of the Cigale; they merely change
its quality and weaken it. The chapels are resonators; they do not
produce the sound, but merely reinforce it by the vibration of their
anterior and posterior membranes; while the sound is modified by the
dampers as they are opened more or less widely.
The actual source of the sound is elsewhere, and is somewhat difficult
for a novice to find. On the outer wall of either chapel, at the ridge
formed by the junction of back and belly, is a tiny aperture with a
horny circumference masked by the overlapping damper. We will call this
the window. This opening gives access to a cavity or sound-chamber,
deeper than the "chapels," but of much smaller capacity. Immediately
behind the attachment of the posterior wings is a slight protuberance,
almost egg-shaped, which is distinguishable, on account of its dull
black colour, from the neighbouring integuments, which are covered with
a silvery down. This protuberance is the outer wall of the
sound-chamber.
Let us cut it boldly away. We shall then lay bare the mechanism which
produces the sound, the _cymbal_. This is a small dry, white membrane,
oval in shape, convex on the outer side, and crossed along its larger
diameter by a bundle of three or four brown nervures, which give it
elasticity. Its entire circumference is rigidly fixed. Let us suppose
that this convex scale is pulled out of shape from the interior, so
that it is slightly flattened and as quickly released; it will
immediately regain its original convexity owing to the elasticity of the
nervures. From this oscillation a ticking sound will result.
Twenty years ago all Paris was buying a silly toy, called, I think, the
cricket or _cri-cri_. It was a short slip of steel fixed by one end to a
metallic base. Pressed out of shape by the thumb and released, it
yielded a very distressing, tinkling _click_. Nothing else was needed to
take the popular mind by storm. The "cricket" had its day of glory.
Oblivion has executed justice upon it so effectually that I fear I shall
not be understood when I recall this celebrated device.
The membranous cymbal and the steel cricket are analogous instruments.
Both produce a sound by reason of the rapid deformation and recovery of
an elastic substance--in one case a convex membrane; in the other a slip
of steel. The "cricket" was bent out of shape by the thumb. How is the
convexity of the cymbals altered? Let us return to the "church" and
break down the yellow curtain which closes the front of each chapel. Two
thick muscular pillars are visible, of a pale orange colour; they join
at an angle, forming a ~V~, of which the point lies on the median line
of the insect, against the lower face of the thorax. Each of these
pillars of flesh terminates suddenly at its upper extremity, as though
cut short, and from the truncated portion rises a short, slender tendon,
which is attached laterally to the corresponding cymbal.
There is the whole mechanism, no less simple than that of the steel
"cricket." The two muscular columns contract and relax, shorten and
lengthen. By means of its terminal thread each sounds its cymbal, by
depressing it and immediately releasing it, when its own elasticity
makes it spring back into shape. These two vibrating scales are the
source of the Cigale's cry.
Do you wish to convince yourself of the efficiency of this mechanism?
Take a Cigale but newly dead and make it sing. Nothing is simpler. Seize
one of these muscular columns with the forceps and pull it in a series
of careful jerks. The extinct _cri-cri_ comes to life again; at each
jerk there is a clash of the cymbal. The sound is feeble, to be sure,
deprived of the amplitude which the living performer is able to give it
by means of his resonating chambers; none the less, the fundamental
element of the song is produced by this anatomist's trick.
Would you, on the other hand, silence a living Cigale?--that obstinate
melomaniac, who, seized in the fingers, deplores his misfortune as
loquaciously as ever he sang the joys of freedom in his tree? It is
useless to violate his chapels, to break his mirrors; the atrocious
mutilation would not quiet him. But introduce a needle by the lateral
aperture which we have named the "window" and prick the cymbal at the
bottom of the sound-box. A little touch and the perforated cymbal is
silent. A similar operation on the other side of the insect and the
insect is dumb, though otherwise as vigorous as before and without any
perceptible wound. Any one not in the secret would be amazed at the
result of my pin-prick, when the destruction of the mirrors and the
other dependencies of the "church" do not cause silence. A tiny
perforation of no importance to the insect is more effectual than
evisceration.
The dampers, which are rigid and solidly built, are motionless. It is
the abdomen itself which, by rising and falling, opens or closes the
doors of the "church." When the abdomen is lowered the dampers exactly
cover the chapels as well as the windows of the sound-boxes. The sound
is then muted, muffled, diminished. When the abdomen rises the chapels
are open, the windows unobstructed, and the sound acquires its full
volume. The rapid oscillations of the abdomen, synchronising with the
contractions of the motor muscles of the cymbals, determine the changing
volume of the sound, which seems to be caused by rapidly repeated
strokes of a fiddlestick.
If the weather is calm and hot, towards mid-day the song of the Cigale
is divided into strophes of several seconds' duration, which are
separated by brief intervals of silence. The strophe begins suddenly. In
a rapid crescendo, the abdomen oscillating with increasing rapidity, it
acquires its maximum volume; it remains for a few seconds at the same
degree of intensity, then becomes weaker by degrees, and degenerates
into a shake, which decreases as the abdomen returns to rest. With the
last pulsations of the belly comes silence; the length of the silent
interval varies according to the state of the atmosphere. Then, of a
sudden, begins a new strophe, a monotonous repetition of the first; and
so on indefinitely.
It often happens, especially during the hours of the sultry afternoons,
that the insect, intoxicated with sunlight, shortens and even suppresses
the intervals of silence. The song is then continuous, but always with
an alternation of crescendo and diminuendo. The first notes are heard
about seven or eight o'clock in the morning, and the orchestra ceases
only when the twilight fails, about eight o'clock at night. The concert
lasts a whole round of the clock. But if the sky is grey and the wind
chilly the Cigale is silent.
The second species, only half the size of the common Cigale, is known in
Provence as the _Cacan_; the name, being a fairly exact imitation of the
sound emitted by the insect. This is the Cigale of the flowering ash,
far more alert and far more suspicious than the common species. Its
harsh, loud song consists of a series of cries--_can! can! can!
can!_--with no intervals of silence subdividing the poem into stanzas.
Thanks to its monotony and its harsh shrillness, it is a most odious
sound, especially when the orchestra consists of hundreds of performers,
as is often the case in my two plane-trees during the dog-days. It is as
though a heap of dry walnuts were being shaken up in a bag until the
shells broke. This painful concert, which is a real torment, offers only
one compensation: the Cigale of the flowering ash does not begin his
song so early as the common Cigale, and does not sing so late in the
evening.
Although constructed on the same fundamental principles, the vocal
organs exhibit a number of peculiarities which give the song its special
character. The sound-box is lacking, which suppresses the entrance to
it, or the window. The cymbal is uncovered, and is visible just behind
the attachment of the hinder wing. It is, as before, a dry white scale,
convex on the outside, and crossed by a bundle of fine reddish-brown
nervures.
[Illustration: 1. THE ADULT CIGALE, FROM BELOW.
2. THE ADULT CIGALE, FROM BELOW.
3. THE CIGALE OF THE FLOWERING ASH, MALE AND FEMALE.]
From the forward side of the first segment of the abdomen project two
short, wide, tongue-shaped projections, the free extremities of which
rest on the cymbals. These tongues may be compared to the blade of a
watchman's rattle, only instead of engaging with the teeth of a rotating
wheel they touch the nervures of the vibrating cymbal. From this fact, I
imagine, results the harsh, grating quality of the cry. It is hardly
possible to verify the fact by holding the insect in the fingers; the
terrified _Cacan_ does not go on singing his usual song.
The dampers do not overlap; on the contrary, they are separated by a
fairly wide interval. With the rigid tongues, appendages of the abdomen,
they half shelter the cymbals, half of which is completely bare. Under
the pressure of the finger the abdomen opens a little at its
articulation with the thorax. But the insect is motionless when it
sings; there is nothing of the rapid vibrations of the belly which
modulate the song of the common Cigale. The chapels are very small;
almost negligible as resonators. There are mirrors, as in the common
Cigale, but they are very small; scarcely a twenty-fifth of an inch in
diameter. In short, the resonating mechanism, so highly developed in the
common Cigale, is here extremely rudimentary. How then is the feeble
vibration of the cymbals re-enforced until it becomes intolerable?
This species of Cigale is a ventriloquist. If we examine the abdomen by
transmitted light, we shall see that the anterior two-thirds of the
abdomen are translucent. With a snip of the scissors we will cut off the
posterior third, to which are relegated, reduced to the strictly
indispensable, the organs necessary to the propagation of the species
and the preservation of the individual. The rest of the abdomen presents
a spacious cavity, and consists simply of the integuments of the walls,
except on the dorsal side, which is lined with a thin muscular layer,
and supports a fine digestive canal, almost a thread. This large cavity,
equal to nearly half the total volume of the insect, is thus almost
absolutely empty. At the back are seen the two motor muscles of the
cymbals, two muscular columns arranged like the limbs of a ~V~. To right
and left of the point of this ~V~ shine the tiny mirrors; and between
the two branches of muscle the empty cavity is prolonged into the depths
of the thorax.
This empty abdomen with its thoracic annex forms an enormous resonator,
such as no other performer in our countryside can boast of. If I close
with my finger the orifice of the truncated abdomen the sound becomes
flatter, in conformity with the laws affecting musical resonators; if I
fit into the aperture of the open body a tube or trumpet of paper the
sound grows louder as well as deeper. With a paper cone corresponding
to the pitch of the note, with its large end held in the mouth of a
test-tube acting as a resonator, we have no longer the cry of the
Cigale, but almost the bellowing of a bull. My little children,
coming up to me by chance at the moment of this acoustic experiment,
fled in terror.
The grating quality of the sound appears to be due to the little tongues
which press on the nervures of the vibrating cymbals; the cause of its
intensity is of course the ample resonator in the abdomen. We must admit
that one must truly have a real passion for song before one would empty
one's chest and stomach in order to make room for a musical-box. The
necessary vital organs are extremely small, confined to a mere corner of
the body, in order to increase the amplitude of the resonating cavity.
Song comes first of all; other matters take the second rank.
It is lucky that the _Cacan_ does not follow the laws of evolution. If,
more enthusiastic in each generation, it could acquire, in the course of
progress, a ventral resonator comparable to my paper trumpets, the South
of France would sooner or later become uninhabitable, and the _Cacan_
would have Provence to itself.
After the details already given concerning the common Cigale it is
hardly needful to tell you how the insupportable _Cacan_ can be reduced
to silence. The cymbals are plainly visible on the exterior. Pierce them
with the point of a needle, and immediately you have perfect silence. If
only there were, in my plane-trees, among the insects which carry
gimlets, some friends of silence like myself, who would devote
themselves to such a task! But no: a note would be lacking in the
majestic symphony of harvest-tide.
We are now familiar with the structure of the musical organ of the
Cigale. Now the question arises: What is the object of these musical
orgies? The reply seems obvious: they are the call of the males inviting
their mates; they constitute a lovers' cantata.
I am going to consider this reply, which is certainly a very natural
one. For thirty years the common Cigale and his unmusical friend the
_Cacan_ have thrust their society upon me. For two months every summer I
have them under my eyes, and their voice in my ears. If I do not listen
to them very willingly I observe them with considerable zeal. I see
them ranged in rows on the smooth rind of the plane-trees, all with
their heads uppermost, the two sexes mingled, and only a few inches
apart.
The proboscis thrust into the bark, they drink, motionless. As the sun
moves, and with it the shadow, they also move round the branch with slow
lateral steps, so as to keep upon that side which is most brilliantly
illuminated, most fiercely heated. Whether the proboscis is at work or
not the song is never interrupted.
Now are we to take their interminable chant for a passionate love-song?
I hesitate. In this gathering the two sexes are side by side. One does
not spend months in calling a person who is at one's elbow. Moreover, I
have never seen a female rush into the midst of even the most deafening
orchestra. Sight is a sufficient prelude to marriage, for their sight is
excellent. There is no need for the lover to make an everlasting
declaration, for his mistress is his next-door neighbour.
Is the song a means of charming, of touching the hard of heart? I doubt
it. I observe no sign of satisfaction in the females; I have never seen
them tremble or sway upon their feet, though their lovers have clashed
their cymbals with the most deafening vigour.
My neighbours the peasants say that at harvest-time the Cigale sings to
them: _Sego, sego, sego!_ (Reap, reap, reap!) to encourage them in their
work. Harvesters of ideas and of ears of grain, we follow the same
calling; the latter produce food for the stomach, the former food for
the mind. Thus I understand their explanation and welcome it as an
example of gracious simplicity.
Science asks for a better explanation, but finds in the insect a world
which is closed to us. There is no possibility of foreseeing, or even
of suggesting the impression produced by this clashing of cymbals upon
those who inspire it. The most I can say is that their impassive
exterior seems to denote a complete indifference. I do not insist that
this is so; the intimate feelings of the insect are an insoluble
mystery.
Another reason for doubt is this: all creatures affected by song have
acute hearing, and this sense of hearing, a vigilant sentinel, should
give warning of danger at the slightest sound. The birds have an
exquisite delicacy of hearing. If a leaf stirs among the branches, if
two passers-by exchange a word, they are suddenly silent, anxious, and
on their guard. But the Cigale is far from sharing in such emotions. It
has excellent sight. Its great faceted eyes inform it of all that
happens to right and left; its three stemmata, like little ruby
telescopes, explore the sky above its head. If it sees us coming it is
silent at once, and flies away. But let us get behind the branch on
which it is singing; let us manoeuvre so as to avoid the five centres
of vision, and then let us speak, whistle, clap the hands, beat two
stones together. For far less a bird which could not see you would stop
its song and fly away terrified. The Cigale imperturbably continues to
sing as if nothing had occurred.
Of my experiences of this kind I will mention only one, the most
remarkable of many.
I borrowed the municipal artillery; that is, the iron boxes which are
charged with gunpowder on the day of the patron saint. The artilleryman
was delighted to load them for the benefit of the Cigales, and to fire
them off for me before my house. There were two of these boxes stuffed
full of powder as though for the most solemn rejoicing. Never was
politician making his electoral progress favoured with a bigger charge.
To prevent damage to my windows the sashes were all left open. The two
engines of detonation were placed at the foot of the plane-trees before
my door, no precautions being taken to mask them. The Cigales singing in
the branches above could not see what was happening below.
There were six of us, spectators and auditors. We waited for a moment of
relative quiet. The number of singers was counted by each of us, as well
as the volume and rhythm of the song. We stood ready, our ears attentive
to the aerial orchestra. The box exploded with a clap of thunder.
No disturbance ensued above. The number of performers was the same, the
rhythm the same, the volume the same. The six witnesses were unanimous:
the loud explosion had not modified the song of the Cigales in the
least. The second box gave an identical result.
What are we to conclude from this persistence of the orchestra, its lack
of surprise or alarm at the firing of a charge? Shall we conclude that
the Cigale is deaf? I am not going to venture so far as that; but if any
one bolder than myself were to make the assertion I really do not know
what reasons I could invoke to disprove it. I should at least be forced
to admit that it is very hard of hearing, and that we may well apply to
it the homely and familiar phrase: to shout like a deaf man.
When the blue-winged cricket, basking on the pebbles of some country
footpath, grows deliciously intoxicated with the heat of the sun and
rubs its great posterior thighs against the roughened edge of its
wing-covers; when the green tree-frog swells its throat in the foliage
of the bushes, distending it to form a resonant cavity when the rain is
imminent, is it calling to its absent mate? By no means. The efforts of
the former produce a scarcely perceptible stridulation; the palpitating
throat of the latter is as ineffectual; and the desired one does not
come.
Does the insect really require to emit these resounding effusions, these
vociferous avowals, in order to declare its passion? Consult the immense
majority whom the conjunction of the sexes leaves silent. In the violin
of the grasshopper, the bagpipe of the tree-frog, and the cymbals of the
_Cacan_ I see only their peculiar means of expressing the joy of living,
the universal joy which every species of animal expresses after its
kind.
If you were to tell me that the Cigales play on their noisy instruments
careless of the sound produced, and merely for the pleasure of feeling
themselves alive, just as we rub our hands in a moment of satisfaction,
I should not be particularly shocked. That there is a secondary object
in their conceit, in which the silent sex is interested, is very
possible and very natural, but it is not as yet proven.[1]
CHAPTER IV
THE CIGALE. THE EGGS AND THEIR HATCHING
The Cigale confides its eggs to dry, slender twigs. All the branches
examined by Réaumur which bore such eggs were branches of the mulberry:
a proof that the person entrusted with the search for these eggs in the
neighbourhood of Avignon did not bring much variety to his quest. I find
these eggs not only on the mulberry-tree, but on the peach, the cherry,
the willow, the Japanese privet, and other trees. But these are
exceptions; what the Cigale really prefers is a slender twig of a
thickness varying from that of a straw to that of a pencil. It should
have a thin woody layer and plenty of pith. If these conditions are
fulfilled the species matters little. I should pass in review all the
semi-ligneous plants of the country were I to catalogue the various
supports which are utilised by the gravid female.
Its chosen twig never lies along the ground; it is always in a more or
less vertical position. It is usually growing in its natural position,
but is sometimes detached; in the latter case it will by chance have
fallen so that it retains its upright position. The insect prefers a
long, smooth, regular twig which can receive the whole of its eggs. The
best batches of eggs which I have found have been laid upon twigs of
the _Spartium junceum_, which are like straws stuffed with pith, and
especially on the upper twigs of the _Asphodelus cerasiferus_, which
rises nearly a yard from the ground before ramifying.
It is essential that the support, no matter what its nature, should be
dead and perfectly dry.
The first operation performed by the Cigale consists in making a series
of slight lacerations, such as one might make with the point of a pin,
which, if plunged obliquely downwards into the twig, would tear the
woody fibres and would compress them so as to form a slight
protuberance.
If the twig is irregular in shape, or if several Cigales have been
working successively at the same point, the distribution of the
punctures is confused; the eye wanders, incapable of recognising the
order of their succession or the work of the individual. One
characteristic is always present, namely, the oblique direction of the
woody fragment which is raised by the perforation, showing that the
Cigale always works in an upright position and plunges its rostrum
downwards in the direction of the twig.
If the twig is regular, smooth, and conveniently long the perforations
are almost equidistant and lie very nearly in a straight line. Their
number varies; it is small when the mother, disturbed in her operations,
has flown away to continue her work elsewhere; but they number thirty or
forty, more or less, when they contain the whole of her eggs.
Each one of the perforations is the entrance to an oblique tunnel, which
is bored in the medullary sheath of the twig. The aperture is not
closed, except by the bunch of woody fibres, which, parted at the moment
when the eggs are laid, recover themselves when the double saw of the
oviduct is removed. Sometimes, but by no means always, you may see
between the fibres a tiny glistening patch like a touch of dried white
of egg. This is only an insignificant trace of some albuminous secretion
accompanying the egg or facilitating the work of the double saw of the
oviduct.
Immediately below the aperture of the perforation is the egg chamber: a
short, tunnel-shaped cavity which occupies almost the whole distance
between one opening and that lying below it. Sometimes the separating
partition is lacking, and the various chambers run into one another, so
that the eggs, although introduced by the various apertures, are
arranged in an uninterrupted row. This arrangement, however, is not the
most usual.
The contents of the chambers vary greatly. I find in each from six to
fifteen eggs. The average is ten. The total number of chambers varying
from thirty to forty, it follows that the Cigale lays from three to four
hundred eggs. Réaumur arrived at the same figures from an examination of
the ovaries.
This is truly a fine family, capable by sheer force of numbers of
surviving the most serious dangers. I do not see that the adult Cigale
is exposed to greater dangers than any other insect: its eye is
vigilant, its departure sudden, and its flight rapid; and it inhabits
heights at which the prowling brigands of the turf are not to be feared.
The sparrow, it is true, will greedily devour it. From time to time he
will deliberately and meditatively descend upon the plane-trees from the
neighbouring roof and snatch up the singer, who squeaks despairingly. A
few blows of the beak and the Cigale is cut into quarters, delicious
morsels for the nestlings. But how often does the bird return without
his prey! The Cigale, foreseeing his attack, empties its intestine in
the eyes of its assailant and flies away.
But the Cigale has a far more terrible enemy than the sparrow. This is
the green grasshopper. It is late, and the Cigales are silent. Drowsy
with light and heat, they have exhausted themselves in producing their
symphonies all day long. Night has come, and with it repose; but a
repose frequently troubled. In the thick foliage of the plane-trees
there is a sudden sound like a cry of anguish, short and strident. It is
the despairing lamentation of the Cigale surprised in the silence by the
grasshopper, that ardent hunter of the night, which leaps upon the
Cigale, seizes it by the flank, tears it open, and devours the contents
of the stomach. After the orgy of music comes night and assassination.
I obtained an insight into this tragedy in the following manner: I was
walking up and down before my door at daybreak when something fell from
the neighbouring plane-tree uttering shrill squeaks. I ran to see what
it was. I found a green grasshopper eviscerating a struggling Cigale. In
vain did the latter squeak and gesticulate; the other never loosed its
hold, but plunged its head into the entrails of the victim and removed
them by little mouthfuls.
[Illustration: 1. THE CIGALE LAYING HER EGGS.
2. THE GREEN GRASSHOPPER, THE FALSE CIGALE OF THE NORTH, DEVOURING THE
TRUE CIGALE, A DWELLER IN THE SOUTH.]
This was instructive. The attack was delivered high up above my head, in
the early morning, while the Cigale was resting; and the struggles of
the unfortunate creature as it was dissected alive had resulted in the
fall of assailant and assailed together. Since then I have often been
the witness of similar assassinations.
I have even seen the grasshopper, full of audacity, launch itself in
pursuit of the Cigale, who fled in terror. So the sparrow-hawk pursues
the skylark in the open sky. But the bird of prey is less ferocious than
the insect; it pursues a creature smaller than itself. The locust, on
the contrary, assails a colossus, far larger and far more vigorous than
its enemy; yet the result is a foregone conclusion, in spite of this
disproportion. With its powerful mandibles, like pincers of steel, the
grasshopper rarely fails to eviscerate its captive, which, being
weaponless, can only shriek and struggle.
The Cigale is an easy prey during its hours of somnolence. Every Cigale
encountered by the ferocious grasshopper on its nocturnal round must
miserably perish. Thus are explained those sudden squeaks of anguish
which are sometimes heard in the boughs during the hours of the night
and early morning, although the cymbals have long been silent. The
sea-green bandit has fallen upon some slumbering Cigale. When I wished
to rear some green grasshoppers I had not far to seek for the diet of my
pensioners; I fed them on Cigales, of which enormous numbers were
consumed in my breeding-cages. It is therefore an established fact that
the green grasshopper, the false Cigale of the North, will eagerly
devour the true Cigale, the inhabitant of the Midi.
But it is neither the sparrow nor the green grasshopper that has forced
the Cigale to produce such a vast number of offspring. The real danger
is elsewhere, as we shall see. The risk is enormous at the moment of
hatching and also when the egg is laid.
Two or three weeks after its escape from the earth--that is, about the
middle of July--the Cigale begins to lay. In order to observe the
process without trusting too much to chance, I took certain precautions
which would, I felt sure, prove successful. The dry Asphodelus is the
support preferred by the insect, as previous observations had assured
me. It was also the plant which best lent itself to my experiments, on
account of its long, smooth stems. Now, during the first years of my
residence in the South I replaced the thistles in my paddock by other
native plants of a less stubborn and prickly species. Among the new
occupants was the asphodel. This was precisely what I needed for my
experiments. I left the dry stems of the preceding year in place, and
when the breeding season arrived I inspected them daily.
I had not long to wait. As early as July 15th I found as many Cigales as
I could wish on the stems of the asphodel, all in process of laying. The
gravid female is always solitary. Each mother has her twig to herself,
and is in no danger of being disturbed during the delicate operation of
laying. When the first occupant has departed another may take her place,
and so on indefinitely. There is abundance of room for all; but each
prefers to be alone as her turn arrives. There is, however, no
unpleasantness of any kind; everything passes most peacefully. If a
female Cigale finds a place which has been already taken she flies away
and seeks another twig directly she discovers her mistake.
The gravid female always retains an upright position at this time, as
indeed she does at other times. She is so absorbed in her task that she
may readily be watched, even through a magnifying glass. The ovipositor,
which is about four-tenths of an inch in length, is plunged obliquely
and up to the hilt into the twig. So perfect is the tool that the
operation is by no means troublesome. We see the Cigale tremble
slightly, dilating and contracting the extremity of the abdomen in
frequent palpitations. This is all that can be seen. The boring
instrument, consisting of a double saw, alternately rises and sinks in
the rind of the twig with a gentle, almost imperceptible movement.
Nothing in particular occurs during the process of laying the eggs. The
insect is motionless, and hardly ten minutes elapse between the first
cut of the ovipositor and the filling of the egg-chamber with eggs.
The ovipositor is then withdrawn with methodical deliberation, in order
that it may not be strained or bent. The egg-chamber closes of its own
accord as the woody fibres which have been displaced return to their
position, and the Cigale climbs a little higher, moving upwards in a
straight line, by about the length of its ovipositor. It then makes
another puncture and a fresh chamber for another ten or twelve eggs. In
this way it scales the twig from bottom to top.
These facts being understood, we are able to explain the remarkable
arrangement of the eggs. The openings in the rind of the twig are
practically equidistant, since each time the Cigale moves upward it is
by a given length, namely, that of the ovipositor. Very rapid in flight,
she is a very idle walker. At the most you may see her, on the living
twig from which she is drinking, moving at a slow, almost solemn pace,
to gain a more sunny point close at hand. On the dry twig in which she
deposits her eggs she observes the same formal habits, and even
exaggerates them, in view of the importance of the operation. She moves
as little as possible, just so far as she must in order to avoid running
two adjacent egg-chambers into one. The extent of each movement upwards
is approximately determined by the depth of the perforation.
The apertures are arranged in a straight line when their number is not
very large. Why, indeed, should the insect wander to right or to left
upon a twig which presents the same surface all over? A lover of the
sun, she chooses that side of the twig which is most exposed to it. So
long as she feels the heat, her supreme joy, upon her back, she will
take good care not to change the position which she finds so delightful
for another in which the sun would fall upon her less directly.
The process of depositing the eggs is a lengthy one when it is carried
out entirely on the same twig. Counting ten minutes for each
egg-chamber, the full series of forty would represent a period of six or
seven hours. The sun will of course move through a considerable distance
before the Cigale can finish her work. In such cases the series of
apertures follows a spiral curve. The insect turns round the stalk as
the sun turns.
Very often as the Cigale is absorbed in her maternal task a diminutive
fly, also full of eggs, busily exterminates the Cigale's eggs as fast as
they are laid.
This insect was known to Réaumur. In nearly all the twigs examined he
found its grub, the cause of a misunderstanding at the beginning of his
researches. But he did not, could not see the audacious insect at work.
It is one of the Chalcididæ, about one-fifth or one-sixth of an inch in
length; entirely black, with knotty antennæ, which are slightly thicker
towards their extremities. The unsheathed ovipositor is implanted in the
under portion of the abdomen, about the middle, and at right angles to
the axis of the body, as in the case of the Leucospis, the pest of the
apiary. Not having taken the precaution to capture it, I do not know
what name the entomologists have bestowed upon it, or even if this dwarf
exterminator of the Cigale has as yet been catalogued. What I am
familiar with is its calm temerity, its impudent audacity in the
presence of the colossus who could crush it with a foot. I have seen as
many as three at once exploiting the unfortunate female. They keep close
behind the Cigale, working busily with their probes, or waiting until
their victim deposits her eggs.
The Cigale fills one of her egg-chambers and climbs a little higher in
order to bore another hole. One of the bandits runs to the abandoned
station, and there, almost under the claws of the giant, and without the
least nervousness, as if it were accomplishing some meritorious action,
it unsheathes its probe and thrusts it into the column of eggs, not by
the open aperture, which is bristling with broken fibres, but by a
lateral fissure. The probes works slowly, as the wood is almost intact.
The Cigale has time to fill the adjacent chamber.
As soon as she has finished one of these midges, the very same that has
been performing its task below her, replaces her and introduces its
disastrous egg. By the time the Cigale departs, her ovaries empty, the
majority of the egg-chambers have thus received the alien egg which will
work the destruction of their contents. A small, quick-hatching grub,
richly nourished on a dozen eggs, will replace the family of the Cigale.
The experience of centuries has taught the Cigale nothing. With her
excellent eyesight she must be able to perceive these terrible sappers
as they hover about her, meditating their crime. Too peaceable giantess!
if you see them why do you not seize them in your talons, crush the
pigmies at their work, so that you may proceed with your travail in
security? But no, you will leave them untouched; you cannot modify your
instincts, even to alleviate your maternal misfortunes.
The eggs of the common Cigale are of a shining ivory white. Conical at
the ends, and elongated in form, they might be compared in shape to the
weaver's shuttle. Their length is about one-tenth of an inch, their
diameter about one-fiftieth. They are packed in a row, slightly
overlapping one another. The eggs of the Cacan are slightly smaller, and
are assembled in regular groups which remind one of microscopical
bundles of cigars. We will consider the eggs of the common Cigale to the
exclusion of the others, as their history is the history of all.
September is not yet over when the shining white as of ivory gives way
to the yellow hue of cheese. During the first days of October you may
see, at the forward end of the egg, two tiny points of chestnut brown,
which are the eyes of the embryo in formation. These two shining eyes,
which almost seem to gaze at one, and the cone-shaped head of the egg,
give it the look of a tiny fish without fins--a fish for whom half a
nut-shell would make a capacious aquarium.
About the same time I notice frequently, on the asphodels in the paddock
and on those of the neighbouring hills, certain indications that the
eggs have recently hatched out. There are certain cast-off articles of
clothing, certain rags and tatters, left on the threshold of the
egg-chamber by the new-born grubs as they leave it and hurry in search
of a new lodging. We shall see in a moment what these vestiges mean.
But in spite of my visits, which were so assiduous as to deserve
success, I had never contrived to see the young Cigales emerge from
their egg-chambers. My domestic researches had been pursued in vain. Two
years running I had collected, in boxes, tubes, and bottles, a hundred
twigs of every kind which were peopled by the eggs of the Cigale; but
not one had shown me what I so desired to witness: the issue of the
new-born Cigales.
Réaumur experienced the same disappointment. He tells us how all the
eggs supplied by his friends were abortive, even when he placed them in
a glass tube thrust under his armpit, in order to keep them at a high
temperature. No, venerable master! neither the temperate shelter of our
studies and laboratories, nor the incubating warmth of our bodies is
sufficient here; we need the supreme stimulant, the kiss of the sun;
after the cool of the mornings, which are already sharp, the sudden
blaze of the superb autumn weather, the last endearments of summer.
It was under such circumstances, when a blazing sun followed a cold
night, that I found the signs of completed incubation; but I always came
too late; the young Cigales had departed. At most I sometimes found one
hanging by a thread to its natal stem and struggling in the air. I
supposed it to be caught in a thread of gossamer, or some shred of
cobweb.
At last, on the 27th of October, despairing of success, I gathered some
asphodels from the orchard, and the armful of dry twigs in which the
Cigales had laid their eggs was taken up to my study. Before giving up
all hope I proposed once more to examine the egg-chambers and their
contents. The morning was cold, and the first fire of the season had
been lit in my room. I placed my little bundle on a chair before the
fire, but without any intention of testing the effect of the heat of the
flames upon the concealed eggs. The twigs, which I was about to cut
open, one by one, were placed there to be within easy reach of my hand,
and for no other reason.
Then, while I was examining a split twig with my magnifying-glass, the
phenomenon which I had given up all hope of observing took place under
my eyes. My bundle of twigs was suddenly alive; scores and scores of the
young larvæ were emerging from their egg-chambers. Their numbers were
such that my ambition as observer was amply satisfied. The eggs were
ripe, on the point of hatching, and the warmth of the fire, bright and
penetrating, had the effect of sunlight in the open. I was quick to
profit by the unexpected piece of good fortune.
At the orifice of the egg-chamber, among the torn fibres of the bark, a
little cone-shaped body is visible, with two black eye-spots; in
appearance it is precisely like the fore portion of the butter-coloured
egg; or, as I have said, like the fore portion of a tiny fish. You would
think that an egg had been somehow displaced, had been removed from the
bottom of the chamber to its aperture. An egg to move in this narrow
passage! a walking egg! No, that is impossible; eggs "do not do such
things!" This is some mistake. We will break open the twig, and the
mystery is unveiled. The actual eggs are where they always were, though
they are slightly disarranged. They are empty, reduced to the condition
of transparent skins, split wide open at the upper end. From them has
issued the singular organism whose most notable characteristics are as
follows:--
In its general form, the configuration of the head and the great black
eyes, the creature, still more than the egg, has the appearance of an
extremely minute fish. A simulacrum of a ventral fin increases the
resemblance. This apparent fin in reality consists of the two
fore-limbs, which, packed in a special sheath, are bent backwards,
stretched out against one another in a straight line. Its small degree
of mobility must enable the grub to escape from the egg-shell and, with
greater difficulty, from the woody tunnel leading to the open air.
Moving outwards a little from the body, and then moving back again, this
lever serves as a means of progression, its terminal hooks being already
fairly strong. The four other feet are still covered by the common
envelope, and are absolutely inert. It is the same with the antennæ,
which can scarcely be seen through the magnifying-glass. The organism
which has issued from the egg is a boat-shaped body with a fin-shaped
limb pointing backwards on the ventral face, formed by the junction of
the two fore-limbs. The segmentation of the body is very clear,
especially on the abdomen. The whole body is perfectly smooth, without
the least suspicion of hair.
What name are we to give to this initial phase of the Cigale--a phase so
strange, so unforeseen, and hitherto unsuspected? Must I amalgamate some
more or less appropriate words of Greek and fabricate a portentous
nomenclature? No, for I feel sure that barbarous alien phrases are only
a hindrance to science. I will call it simply the _primary larva_, as I
have done in the case of the Meloides, the Leucospis, and the Anthrax.
The form of the primary larva of the Cigale is eminently adapted to its
conditions and facilitates its escape. The tunnel in which the egg is
hatched is very narrow, leaving only just room for passage. Moreover,
the eggs are arranged in a row, not end to end, but partially
overlapping. The larva escaping from the hinder ranks has to squeeze
past the empty shells, still in position, of the eggs which have already
hatched, so that the narrowness of the passage is increased by the empty
egg-shells. Under these conditions the larva as it will be presently,
when it has torn its temporary wrappings, would be unable to effect the
difficult passage. With the encumbrance of antennæ, with long limbs
spreading far out from the axis of the body, with curved, pointed talons
which hook themselves into their medium of support, everything would
militate against a prompt liberation. The eggs in one chamber hatch
almost simultaneously. It is therefore essential that the first-born
larvæ should hurry out of their shelter as quickly as possible, leaving
the passage free for those behind them. Hence the boat-like shape, the
smooth hairless body without projections, which easily squeezes its way
past obstructions. The primary larva, with its various appendages
closely wrapped against its body by a common sheath, with its fish-like
form and its single and only partially movable limb, is perfectly
adapted to make the difficult passage to the outer air.
This phase is of short duration. Here, for instance, a migrating larva
shows its head, with its big black eyes, and raises the broken fibres of
the entrance. It gradually works itself forward, but so slowly that the
magnifying-glass scarcely reveals its progress. At the end of half an
hour at the shortest we see the entire body of the creature; but the
orifice by which it is escaping still holds it by the hinder end of the
body.
Then, without further delay, the coat which it wears for this rough
piece of work begins to split, and the larva skins itself, coming out of
its wrappings head first. It is then the normal larva; the only form
known to Réaumur. The rejected coat forms a suspensory thread, expanding
at its free end to form a little cup. In this cup is inserted the end of
the abdomen of the larva, which, before allowing itself to fall to
earth, takes a sun-bath, grows harder, stretches itself, and tries its
strength, lightly swinging at the end of its life-line.
This little flea, as Réaumur calls it, first white, then amber-coloured,
is precisely the larva which will delve in the earth. The antennæ, of
fair length, are free and waving to and fro; the limbs are bending at
their articulations; the fore-limbs, which are relatively powerful, open
and shut their talons. I can scarcely think of any more curious
spectacle than that of this tiny gymnast hanging by its tail, swinging
to the faintest breath, and preparing in the air for its entry into the
world. It hangs there for a variable period; some larvæ let themselves
fall at the end of half an hour; others spend hours in their
long-stemmed cup; some even remain suspended until the following day.
Whether soon or late, the fall of the larva leaves suspended the thread
by which it hung, the wrappings of the primary larva. When all the brood
have disappeared, the aperture of the nest is thus hung with a branch of
fine, short threads, twisted and knotted together, like dried white of
egg. Each thread is expanded into a tiny cup at its free end. These are
very delicate and ephemeral relics, which perish at a touch. The least
wind quickly blows them away.
Let us return to the larva. Sooner or later, as we have seen, it falls
to the ground, either by accident or intention. The tiny creature, no
bigger than a flea, has preserved its tender newly-hatched flesh from
contact with the rough earth by hanging in the air until its tissues
have hardened. Now it plunges into the troubles of life.
I foresee a thousand dangers ahead. A mere breath of wind may carry this
atom away, and cast it on that inaccessible rock in the midst of a rut
in the road which still contains a little water; or on the sand, the
region of famine where nothing grows; or upon a soil of clay, too
tenacious to be tunnelled. These mortal accidents are frequent, for
gusts of wind are frequent in the windy and already severe weather of
the end of October.
This delicate organism requires a very soft soil, which can easily be
entered, so that it may immediately obtain a suitable shelter. The cold
days are coming; soon the frosts will be here. To wander on the surface
would expose it to grave perils. It must contrive without delay to
descend into the earth, and that to no trivial depth. This is the unique
and imperative condition of safety, and in many cases it is impossible
of realisation. What use are the claws of this tiny flea against rock,
sandstone, or hardened clay? The creature must perish if it cannot find
a subterranean refuge in good time.
Everything goes to show that the necessity of this first foothold on the
soil, subject as it is to so many accidents, is the cause of the great
mortality in the Cigale family. The little black parasite, the destroyer
of eggs, in itself evokes the necessity of a large batch of eggs; and
the difficulty which the larva experiences in effecting a safe lodgment
in the earth is yet another explanation of the fact that the maintenance
of the race at its proper strength requires a batch of three or four
hundred eggs from each mother. Subject to many accidents, the Cigale is
fertile to excess. By the prodigality of her ovaries she conjures the
host of perils which threaten her offspring.
During the rest of my experiment I can at least spare the larvæ the
worst difficulties of their first establishment underground. I take some
soil from the heath, which is very soft and almost black, and I pass it
through a fine sieve. Its colour will enable me more easily to find the
tiny fair-skinned larvæ when I wish to inform myself of passing events;
its lightness makes it a suitable refuge for such weak and fragile
beings. I pack it Pretty firmly in a glass vase; I plant in it a little
tuft of thyme; I sow in it a few grains of wheat. There is no hole at
the bottom of the vase, although there should be one for the benefit of
the thyme and the corn; but the captives would find it and escape by it.
The plantation and the crop will suffer from this lack of drainage, but
at least I am sure of recovering my larvæ with the help of patience and
a magnifying-glass. Moreover, I shall go gently in the matter of
irrigation, giving only just enough water to save the plants from
perishing.
When all is in order, and when the wheat is beginning to shoot, I place
six young larvæ of the Cigale on the surface of the soil. The tiny
creatures begin to pace hither and thither; they soon explore the
surface of their world, and some try vainly to climb the sides of the
vase. Not one of them seems inclined to bury itself; so that I ask
myself anxiously what can be the object of their prolonged and active
explorations. Two hours go by, but their wanderings continue.
What do they want? Food? I offer them some tiny bulbs with bundles of
sprouting roots, a few fragments of leaves and some fresh blades of
grass. Nothing tempts them; nothing brings them to a standstill.
Apparently they are seeking for a favourable point before descending
into the earth. But there is no need for this hesitating exploration on
the soil I have prepared for them; the whole area, or so it seems to me,
lends itself excellently to the operations which I am expecting to see
them commence. Yet apparently it will not answer the purpose.
Under natural conditions a little wandering might well be indispensable.
Spots as soft as my bed of earth from the roots of the briar-heather,
purged of all hard bodies and finely sifted, are rare in nature. Coarse
soils are more usual, on which the tiny creatures could make no
impression. The larva must wander at hazard, must make a pilgrimage of
indefinite duration before finding a favourable place. Very many, no
doubt, perish, exhausted by their fruitless search. A voyage of
exploration in a country a few inches wide evidently forms part of the
curriculum of young Cigales. In my glass prison, so luxuriously
furnished, this pilgrimage is useless. Never mind: it must be
accomplished according to the consecrated rites.
At last my wanderers grow less excited. I see them attack the earth with
the curved talons of their fore-limbs, digging their claws into it and
making such an excavation as the point of a thick needle would enter.
With a magnifying-glass I watch their picks at work. I see their talons
raking atom after atom of earth to the surface. In a few minutes there
is a little gaping well. The larva climbs downwards and buries itself,
henceforth invisible.
On the morrow I turn out the contents of the vase without breaking the
mould, which is held together by the roots of the thyme and the wheat. I
find all my larvæ at the bottom, arrested by the glass. In twenty-four
hours they had sunk themselves through the entire thickness of the
earth--a matter of some four inches. But for obstacle at the bottom they
would have sunk even further.
On the way they have probably encountered the rootlets of my little
plantation. Did they halt in order to take a little nourishment by
implanting their proboscis? This is hardly probable, for a few rootlets
were pressed against the bottom of the glass, but none of my prisoners
were feeding. Perhaps the shock of reversing the pot detached them.
It is obvious that underground there is no other nourishment for them
than the sap of roots. Adult or larva, the Cigale is a strict
vegetarian. As an adult insect it drinks the sap of twigs and branches;
as a larva it sucks the sap of roots. But at what stage does it take the
first sip? That I do not know as yet, but the foregoing experiment seems
to show that the newly hatched larva is in greater haste to burrow deep
into the soil, so as to obtain shelter from the coming winter, than to
station itself at the roots encountered in its passage downwards.
I replace the mass of soil in the vase, and the six exhumed larvæ are
once more placed on the surface of the soil. This time they commence to
dig at once, and have soon disappeared. Finally the vase is placed in my
study window, where it will be subject to the influences, good and ill,
of the outer air.
A month later, at the end of November, I pay the young Cigales a second
visit. They are crouching, isolated at the bottom of the mould. They do
not adhere to the roots; they have not grown; their appearance has not
altered. Such as they were at the beginning of the experiment, such they
are now, but rather less active. Does not this lack of growth during
November, the mildest month of winter, prove that no nourishment is
taken until the spring?
The young Sitares, which are also very minute, directly they issue from
the egg at the entrance of the tubes of the Anthrophorus, remain
motionless, assembled in a heap, and pass the whole of the winter in a
state of complete abstinence. The young Cigales apparently behave in a
very similar fashion. Once they have burrowed to such depths as will
safeguard them from the frosts they sleep in solitude in their winter
quarters, and await the return of spring before piercing some
neighbouring root and taking their first repast.
I have tried unsuccessfully to confirm these deductions by observation.
In April I unpotted my plant of thyme for the third time. I broke up the
mould and spread it under the magnifying-glass. It was like looking for
needles in a haystack; but at last I recovered my little Cigales. They
were dead, perhaps of cold, in spite of the bell-glass with which I had
covered the pot, or perhaps of starvation, if the thyme was not a
suitable food-plant. I give up the problem as too difficult of solution.
To rear such larvæ successfully one would require a deep, extensive bed
of earth which would shelter them from the winter cold; and, as I do not
know what roots they prefer, a varied vegetation, so that the little
creatures could choose according to their taste. These conditions are by
no means impracticable, but how, in the large earthy mass, containing at
least a cubic yard of soil, should we recover the atoms I had so much
trouble to find in a handful of black soil from the heath? Moreover,
such a laborious search would certainly detach the larva from its root.
The early subterranean life of the Cigale escapes us. That of the
maturer larva is no better known. Nothing is more common, while digging
in the fields to any depth, to find these impetuous excavators under the
spade; but to surprise them fixed upon the roots which incontestably
nourish them is quite another matter. The disturbance of the soil warns
the larva of danger. It withdraws its proboscis in order to retreat
along its galleries, and when the spade uncovers it has ceased to feed.
If the hazards of field-work, with its inevitable disturbance of the
larvæ, cannot teach us anything of their subterranean habits, we can at
least learn something of the duration of the larval stage. Some obliging
farmers, who were making some deep excavations in March, were good
enough to collect for me all the larvæ, large and small, unearthed in
the course of their labour. The total collection amounted to several
hundreds. They were divided, by very clearly marked differences of size,
into three categories: the large larvæ, with rudiments of wings, such as
those larvæ caught upon leaving the earth possess; the medium-sized, and
the small. Each of these stages must correspond to a different age. To
these we may add the larvæ produced by the last hatching of eggs,
creatures too minute to be noticed by my rustic helpers, and we obtain
four years as the probable term of the larvæ underground.
The length of their aerial existence is more easily computed. I hear the
first Cigales about the summer solstice. A month later the orchestra has
attained its full power. A very few late singers execute their feeble
solos until the middle of September. This is the end of the concert. As
all the larvæ do not issue from the ground at the same time, it is
evident that the singers of September are not contemporary with those
that began to sing at the solstice. Taking the average between these two
dates, we get five weeks as the probable duration of the Cigales' life
on earth.
Four years of hard labour underground, and a month of feasting in the
sun; such is the life of the Cigale. Do not let us again reproach the
adult insect with his triumphant delirium. For four years, in the
darkness he has worn a dirty parchment overall; for four years he has
mined the soil with his talons, and now the mud-stained sapper is
suddenly clad in the finest raiment, and provided with wings that rival
the bird's; moreover, he is drunken with heat and flooded with light,
the supreme terrestrial joy. His cymbals will never suffice to celebrate
such felicity, so well earned although so ephemeral.
CHAPTER V
THE MANTIS.--THE CHASE
There is another creature of the Midi which is quite as curious and
interesting as the Cigale, but much less famous, as it is voiceless. If
Providence had provided it with cymbals, which are a prime element of
popularity, it would soon have eclipsed the renown of the celebrated
singer, so strange is its shape, and so peculiar its manners. It is
called by the Provençals _lou Prègo-Diéu_, the creature which prays to
God. Its official name is the Praying Mantis (_Mantis religiosa_, Lin.).
For once the language of science and the vocabulary of the peasant
agree. Both represent the Mantis as a priestess delivering oracles, or
an ascetic in a mystic ecstasy. The comparison is a matter of antiquity.
The ancient Greeks called the insect [Greek: Mantis], the divine, the
prophet. The worker in the fields is never slow in perceiving analogies;
he will always generously supplement the vagueness of the facts. He has
seen, on the sun-burned herbage of the meadows, an insect of commanding
appearance, drawn up in majestic attitude. He has noticed its wide,
delicate wings of green, trailing behind it like long linen veils; he
has seen its fore-limbs, its arms, so to speak, raised towards to the
sky in a gesture of invocation. This was enough: popular imagination
has done the rest; so that since the period of classical antiquity the
bushes have been peopled with priestesses emitting oracles and nuns in
prayer.
Good people, how very far astray your childlike simplicity has led you!
These attitudes of prayer conceal the most atrocious habits; these
supplicating arms are lethal weapons; these fingers tell no rosaries,
but help to exterminate the unfortunate passer-by. It is an exception
that we should never look for in the vegetarian family of the
Orthoptera, but the Mantis lives exclusively upon living prey. It is the
tiger of the peaceful insect peoples; the ogre in ambush which demands a
tribute of living flesh. If it only had sufficient strength its
blood-thirsty appetites, and its horrible perfection of concealment
would make it the terror of the countryside. The _Prègo-Diéu_ would
become a Satanic vampire.
Apart from its lethal weapon the Mantis has nothing about it to inspire
apprehension. It does not lack a certain appearance of graciousness,
with its slender body, its elegant waist-line, its tender green
colouring, and its long gauzy wings. No ferocious jaws, opening like
shears; on the contrary, a fine pointed muzzle which seems to be made
for billing and cooing. Thanks to a flexible neck, set freely upon the
thorax, the head can turn to right or left as on a pivot, bow, or raise
itself high in the air. Alone among insects, the Mantis is able to
direct its gaze; it inspects and examines; it has almost a physiognomy.
There is a very great contrast between the body as a whole, which has a
perfectly peaceable aspect, and the murderous fore-limbs. The haunch of
the fore-limb is unusually long and powerful. Its object is to throw
forward the living trap which does not wait for the victim, but goes in
search of it. The snare is embellished with a certain amount of
ornamentation. On the inner face the base of the haunch is decorated
with a pretty black spot relieved by smaller spots of white, and a few
rows of fine pearly spots complete the ornamentation.
The thigh, still longer, like a flattened spindle, carries on the
forward half of the lower face a double row of steely spines. The
innermost row contains a dozen, alternately long and black and short and
green. This alternation of unequal lengths makes the weapon more
effectual for holding. The outer row is simpler, having only four teeth.
Finally, three needle-like spikes, the longest of all, rise behind the
double series of spikes. In short, the thigh is a saw with two parallel
edges, separated by a groove in which the foreleg lies when folded.
The foreleg, which is attached to the thigh by a very flexible
articulation, is also a double-edged saw, but the teeth are smaller,
more numerous, and closer than those of the thigh. It terminates in a
strong hook, the point of which is as sharp as the finest needle: a hook
which is fluted underneath and has a double blade like a pruning-knife.
A weapon admirably adapted for piercing and tearing, this hook has
sometimes left me with visible remembrances. Caught in turn by the
creature which I had just captured, and not having both hands free, I
have often been obliged to get a second person to free me from my
tenacious captive! To free oneself by violence without disengaging the
firmly implanted talons would result in lacerations such as the thorns
of a rosebush will produce. None of our insects is so inconvenient to
handle. The Mantis digs its knife-blades into your flesh, pierces you
with its needles, seizes you as in a vice, and renders self-defence
almost impossible if, wishing to take your quarry alive, you refrain
from crushing it out of existence.
When the Mantis is in repose its weapons are folded and pressed against
the thorax, and are perfectly inoffensive in appearance. The insect is
apparently praying. But let a victim come within reach, and the attitude
of prayer is promptly abandoned. Suddenly unfolded, the three long
joints of the deadly fore-limbs shoot out their terminal talons, which
strike the victim and drag it backwards between the two saw-blades of
the thighs. The vice closes with a movement like that of the forearm
upon the upper arm, and all is over; crickets, grasshoppers, and even
more powerful insects, once seized in this trap with its four rows of
teeth, are lost irreparably. Their frantic struggles will never release
the hold of this terrible engine of destruction.
The habits of the Mantis cannot be continuously studied in the freedom
of the fields; the insect must be domesticated. There is no difficulty
here; the Mantis is quite indifferent to imprisonment under glass,
provided it is well fed. Offer it a tasty diet, feed it daily, and it
will feel but little regret for its native thickets.
For cages I use a dozen large covers of wire gauze, such as are used in
the larder to protect meat from the flies. Each rests upon a tray full
of sand. A dry tuft of thyme and a flat stone on which the eggs may be
laid later on complete the furnishing of such a dwelling. These cages
are placed in a row on the large table in my entomological laboratory,
where the sun shines on them during the greater part of the day. There
I install my captives; some singly, some in groups.
It is in the latter half of August that I begin to meet with the adult
insect on the faded herbage and the brambles at the roadside. The
females, whose bellies are already swollen, are more numerous every day.
Their slender companions, on the other hand, are somewhat rare, and I
often have some trouble in completing my couples; whose relations will
finally be terminated by a tragic consummation. But we will reserve
these amenities for a later time, and will consider the females first.
They are tremendous eaters, so that their entertainment, when it lasts
for some months is not without difficulties. Their provisions must be
renewed every day, for the greater part are disdainfully tasted and
thrown aside. On its native bushes I trust the Mantis is more
economical. Game is not too abundant, so that she doubtless devours her
prey to the last atom; but in my cages it is always at hand. Often,
after a few mouthfuls, the insect will drop the juicy morsel without
displaying any further interest in it. Such is the ennui of captivity!
To provide them with a luxurious table I have to call in assistants. Two
or three of the juvenile unemployed of my neighbourhood, bribed by
slices of bread and jam or of melon, search morning and evening on the
neighbouring lawns, where they fill their game-bags, little cases made
from sections of reeds, with living grasshoppers and crickets. On my own
part, I make a daily tour of the paddock, net in hand, with the object
of obtaining some choice dish for my guests.
These particular captures are destined to show me just how far the
vigour and audacity of the Mantis will lead it. They include the large
grey cricket (_Pachytylus cinerascens_, Fab.), which is larger than the
creature which devours it; the white-faced Decticus, armed with powerful
mandibles from which it is wise to guard one's fingers; the grotesque
Truxalis, wearing a pyramidal mitre on its head; and the Ephippigera of
the vineyards, which clashes its cymbals and carries a sabre at the end
of its barrel-shaped abdomen. To this assortment of disobliging
creatures let us add two horrors: the silky Epeirus, whose disc-shaped
scalloped abdomen is as big as a shilling, and the crowned Epeirus,
which is horribly hairy and corpulent.
I cannot doubt that the Mantis attacks such adversaries in a state of
nature when I see it, under my wire-gauze covers, boldly give battle to
whatever is placed before it. Lying in wait among the bushes it must
profit by the prizes bestowed upon it by hazard, as in its cage it
profits by the wealth of diet due to my generosity. The hunting of such
big game as I offer, which is full of danger, must form part of the
creature's usual life, though it may be only an occasional pastime,
perhaps to the great regret of the Mantis.
Crickets of all kinds, butterflies, bees, large flies of many species,
and other insects of moderate size: such is the prey that we habitually
find in the embrace of the murderous arms of the Mantis. But in my cages
I have never known the audacious huntress to recoil before any other
insect. Grey cricket, Decticus, Epeirus or Truxalis, sooner or later all
are harpooned, held motionless between the saw-edges of the arms, and
deliciously crunched at leisure. The process deserves a detailed
description.
At the sight of a great cricket, which thoughtlessly approaches along
the wire-work of the cover, the Mantis, shaken by a convulsive start,
suddenly assumes a most terrifying posture. An electric shock would not
produce a more immediate result. The transition is so sudden, the
mimicry so threatening, that the unaccustomed observer will draw back
his hand, as though at some unknown danger. Seasoned as I am, I myself
must confess to being startled on occasions when my thoughts have been
elsewhere. The creature spreads out like a fan actuated by a spring, or
a fantastic Jack-in-the-box.
The wing-covers open, and are thrust obliquely aside; the wings spring
to their full width, standing up like parallel screens of transparent
gauze, forming a pyramidal prominence which dominates the back; the end
of the abdomen curls upwards crosier-wise, then falls and unbends itself
with a sort of swishing noise, a _pouf! pouf!_ like the sound emitted by
the feathers of a strutting turkey-cock. One is reminded of the puffing
of a startled adder.
Proudly straddling on its four hind-claws, the insect holds its long
body almost vertical. The murderous fore-limbs, at first folded and
pressed against one another on the thorax, open to their full extent,
forming a cross with the body, and exhibiting the axillæ ornamented with
rows of pearls, and a black spot with a central point of white. These
two eyes, faintly recalling those of the peacock's tail, and the fine
ebony embossments, are part of the blazonry of conflict, concealed upon
ordinary occasions. Their jewels are only assumed when they make
themselves terrible and superb for battle.
Motionless in its weird position, the Mantis surveys the acridian, its
gaze fixed upon it, its head turning gently as on a pivot as the other
changes place. The object of this mimicry seems evident; the Mantis
wishes to terrorise its powerful prey, to paralyse it with fright; for
if not demoralised by fear the quarry might prove too dangerous.
Does it really terrify its prey? Under the shining head of the Decticus,
behind the long face of the cricket, who is to say what is passing? No
sign of emotion can reveal itself upon these immovable masks. Yet it
seems certain that the threatened creature is aware of its danger. It
sees, springing up before it, a terrible spectral form with talons
outstretched, ready to fall upon it; it feels itself face to face with
death, and fails to flee while yet there is time. The creature that
excels in leaping, and might so easily escape from the threatening
claws, the wonderful jumper with the prodigious thighs, remains
crouching stupidly in its place, or even approaches the enemy with
deliberate steps.[2]
It is said that young birds, paralysed with terror by the gaping mouth
of a serpent, or fascinated by its gaze, will allow themselves to be
snatched from the nest, incapable of movement. The cricket will often
behave in almost the same way. Once within reach of the enchantress, the
grappling-hooks are thrown, the fangs strike, the double saws close
together and hold the victim in a vice. Vainly the captive struggles;
his mandibles chew the air, his desperate kicks meet with no resistance.
He has met with his fate. The Mantis refolds her wings, the standard of
battle; she resumes her normal pose, and the meal commences.
In attacking the Truxalis and the Ephippigera, less dangerous game than
the grey cricket and the Decticus, the spectral pose is less imposing
and of shorter duration. It is often enough to throw forward the talons;
this is so in the case of the Epeirus, which is seized by the middle of
the body, without a thought of its venomous claws. With the smaller
crickets, which are the customary diet in my cages as at liberty, the
Mantis rarely employs her means of intimidation; she merely seizes the
heedless passer-by as she lies in wait.
When the insect to be captured may present some serious resistance, the
Mantis is thus equipped with a pose which terrifies or perplexes,
fascinates or absorbs the prey, while it enables her talons to strike
with greater certainty. Her gins close on a demoralised victim,
incapable of or unready for defence. She freezes the quarry with fear or
amazement by suddenly assuming the attitude of a spectre.
The wings play an important part in this fantastic pose. They are very
wide, green on the outer edge, but colourless and transparent elsewhere.
Numerous nervures, spreading out fan-wise, cross them in the direction
of their length. Others, transversal but finer, cut the first at right
angles, forming with them a multitude of meshes. In the spectral
attitude the wings are outspread and erected in two parallel planes
which are almost in contact, like the wings of butterflies in repose.
Between the two the end of the abdomen rapidly curls and uncurls. From
the rubbing of the belly against the network of nervures proceeds the
species of puffing sound which I have compared to the hissing of an
adder in a posture of defence. To imitate this curious sound it is
enough rapidly to stroke the upper face of an outstretched wing with the
tip of the finger-nail.
In a moment of hunger, after a fast of some days, the large grey
cricket, which is as large as the Mantis or larger, will be entirely
consumed with the exception of the wings, which are too dry. Two hours
are sufficient for the completion of this enormous meal. Such an orgy is
rare. I have witnessed it two or three times, always asking myself where
the gluttonous creature found room for so much food, and how it
contrived to reverse in its own favour the axiom that the content is
less than that which contains it. I can only admire the privileges of a
stomach in which matter is digested immediately upon entrance, dissolved
and made away with.
The usual diet of the Mantis under my wire cages consists of crickets of
different species and varying greatly in size. It is interesting to
watch the Mantis nibbling at its cricket, which it holds in the vice
formed by its murderous fore-limbs. In spite of the fine-pointed muzzle,
which hardly seems made for such ferocity, the entire insect disappears
excepting the wings, of which only the base, which is slightly fleshy,
is consumed. Legs, claws, horny integuments, all else is eaten.
Sometimes the great hinder thigh is seized by the knuckle, carried to
the mouth, tasted, and crunched with a little air of satisfaction. The
swollen thigh of the cricket might well be a choice "cut" for the
Mantis, as a leg of lamb is for us!
The attack on the victim begins at the back of the neck or base of the
head. While one of the murderous talons holds the quarry gripped by the
middle of the body, the other presses the head downwards, so that the
articulation between the back and the neck is stretched and opens
slightly. The snout of the Mantis gnaws and burrows into this undefended
spot with a certain persistence, and a large wound is opened in the
neck. At the lesion of the cephalic ganglions the struggles of the
cricket grow less, and the victim becomes a motionless corpse. Thence,
unrestricted in its movements, this beast of prey chooses its mouthfuls
at leisure.
CHAPTER VI
THE MANTIS.--COURTSHIP
The little we have seen of the customs of the Mantis does not square
very well with the popular name for the insect. From the term
_Prègo-Diéu_ we should expect a peaceful placid creature, devoutly
self-absorbed; and we find a cannibal, a ferocious spectre, biting open
the heads of its captives after demoralising them with terror. But we
have yet to learn the worst. The customs of the Mantis in connection
with its own kin are more atrocious even than those of the spiders, who
bear an ill repute in this respect.
To reduce the number of cages on my big laboratory table, to give myself
a little more room, while still maintaining a respectable menagerie, I
installed several females under one cover. There was sufficient space in
the common lodging and room for the captives to move about, though for
that matter they are not fond of movement, being heavy in the abdomen.
Crouching motionless against the wire work of the cover, they will
digest their food or await a passing victim. They lived, in short, just
as they lived on their native bushes.
Communal life has its dangers. When the hay is low in the manger
donkeys grow quarrelsome, although usually so pacific. My guests might
well, in a season of dearth, have lost their tempers and begun to fight
one another; but I was careful to keep the cages well provided with
crickets, which were renewed twice a day. If civil war broke out famine
could not be urged in excuse.
At the outset matters did not go badly. The company lived in peace, each
Mantis pouncing upon and eating whatever came her way, without
interfering with her neighbours. But this period of concord was of brief
duration. The bellies of the insects grew fuller: the eggs ripened in
their ovaries: the time of courtship and the laying season was
approaching. Then a kind of jealous rage seized the females, although no
male was present to arouse such feminine rivalry. The swelling of the
ovaries perverted my flock, and infected them with an insane desire to
devour one another. There were threats, horrid encounters, and cannibal
feasts. Once more the spectral pose was seen, the hissing of the wings,
and the terrible gesture of the talons outstretched and raised above the
head. The females could not have looked more terrible before a grey
cricket or a Decticus. Without any motives that I could see, two
neighbours suddenly arose in the attitude of conflict. They turned their
heads to the right and the left, provoking one another, insulting one
another. The _pouf! pouf!_ of the wings rubbed by the abdomen sounded
the charge. Although the duel was to terminate at the first scratch,
without any more serious consequence, the murderous talons, at first
folded, open like the leaves of a book, and are extended laterally to
protect the long waist and abdomen. The pose is superb, but less
terrific than that assumed when the fight is to be to the death.
Then one of the grappling-hooks with a sudden spring flies out and
strikes the rival; with the same suddenness it flies back and assumes a
position of guard. The adversary replies with a riposte. The fencing
reminds one not a little of two cats boxing one another's ears. At the
first sign of blood on the soft abdomen, or even at the slightest wound,
one admits herself to be conquered and retires. The other refurls her
battle standard and goes elsewhere to meditate the capture of a cricket,
apparently calm, but in reality ready to recommence the quarrel.
Very often the matter turns out more tragically. In duels to the death
the pose of attack is assumed in all its beauty. The murderous talons
unfold and rise in the air. Woe to the vanquished! for the victor seizes
her in her vice-like grip and at once commences to eat her; beginning,
needless to say, at the back of the neck. The odious meal proceeds as
calmly as if it were merely a matter of munching a grasshopper; and the
survivor enjoys her sister quite as much as lawful game. The spectators
do not protest, being only too willing to do the like on the first
occasion.
Ferocious creatures! It is said that even wolves do not eat one another.
The Mantis is not so scrupulous; she will eat her fellows when her
favourite quarry, the cricket, is attainable and abundant.
These observations reach a yet more revolting extreme. Let us inquire
into the habits of the insect at breeding time, and to avoid the
confusion of a crowd let us isolate the couples under different covers.
Thus each pair will have their own dwelling, where nothing can trouble
their honeymoon. We will not forget to provide them with abundant food;
there shall not be the excuse of hunger for what is to follow.
We are near the end of August. The male Mantis, a slender and elegant
lover, judges the time to be propitious. He makes eyes at his powerful
companion; he turns his head towards her; he bows his neck and raises
his thorax. His little pointed face almost seems to wear an expression.
For a long time he stands thus motionless, in contemplation of the
desired one. The latter, as though indifferent, does not stir. Yet the
lover has seized upon a sign of consent: a sign of which I do not know
the secret. He approaches: suddenly he erects his wings, which are
shaken with a convulsive tremor.
This is his declaration. He throws himself timidly on the back of his
corpulent companion; he clings to her desperately, and steadies himself.
The prelude to the embrace is generally lengthy, and the embrace will
sometimes last for five or six hours.
Nothing worthy of notice occurs during this time. Finally the two
separate, but they are soon to be made one flesh in a much more intimate
fashion. If the poor lover is loved by his mistress as the giver of
fertility, she also loves him as the choicest of game. During the day,
or at latest on the morrow, he is seized by his companion, who first
gnaws through the back of his neck, according to use and wont, and then
methodically devours him, mouthful by mouthful, leaving only the wings.
Here we have no case of jealousy, but simply a depraved taste.
I had the curiosity to wonder how a second male would be received by a
newly fecundated female. The result of my inquiry was scandalous. The
Mantis in only too many cases is never sated with embraces and conjugal
feasts. After a rest, of variable duration, whether the eggs have been
laid or not, a second male is welcomed and devoured like the first. A
third succeeds him, does his duty, and affords yet another meal. A
fourth suffers a like fate. In the course of two weeks I have seen the
same Mantis treat seven husbands in this fashion. She admitted all to
her embraces, and all paid for the nuptial ecstasy with their lives.
There are exceptions, but such orgies are frequent. On very hot days,
when the atmospheric tension is high, they are almost the general rule.
At such times the Mantis is all nerves. Under covers which contain large
households the females devour one another more frequently than ever;
under the covers which contain isolated couples the males are devoured
more eagerly than usual when their office has been fulfilled.
I might urge, in mitigation of these conjugal atrocities, that the
Mantis does not commit them when at liberty. The male, his function once
fulfilled, surely has time to wander off, to escape far away, to flee
the terrible spouse, for in my cages he is given a respite, often of a
whole day. What really happens by the roadside and in the thickets I do
not know; chance, a poor schoolmistress, has never instructed me
concerning the love-affairs of the Mantis when at liberty. I am obliged
to watch events in my laboratory, where the captives, enjoying plenty of
sunshine, well nourished, and comfortably lodged, do not seem in any way
to suffer from nostalgia. They should behave there as they behave under
normal conditions.
Alas! the facts force me to reject the statement that the males have
time to escape; for I once surprised a male, apparently in the
performance of his vital functions, holding the female tightly
embraced--but he had no head, no neck, scarcely any thorax! The female,
her head turned over her shoulder, was peacefully browsing on the
remains of her lover! And the masculine remnant, firmly anchored,
continued its duty!
Love, it is said, is stronger than death! Taken literally, never has an
aphorism received a more striking confirmation. Here was a creature
decapitated, amputated as far as the middle of the thorax; a corpse
which still struggled to give life. It would not relax its hold until
the abdomen itself, the seat of the organs of procreation, was attacked.
The custom of eating the lover after the consummation of the nuptials,
of making a meal of the exhausted pigmy, who is henceforth good for
nothing, is not so difficult to understand, since insects can hardly be
accused of sentimentality; but to devour him during the act surpasses
anything that the most morbid mind could imagine. I have seen the thing
with my own eyes, and I have not yet recovered from my surprise.
Could this unfortunate creature have fled and saved himself, being thus
attacked in the performance of his functions? No. We must conclude that
the loves of the Mantis are fully as tragic, perhaps even more so, than
those of the spider. I do not deny that the limited area of the cage may
favour the massacre of the males; but the cause of such butchering must
be sought elsewhere. It is perhaps a reminiscence of the carboniferous
period when the insect world gradually took shape through prodigious
procreation. The Orthoptera, of which the Mantes form a branch, are the
first-born of the insect world.
Uncouth, incomplete in their transformation, they wandered amidst the
arborescent foliage, already flourishing when none of the insects sprung
of more complex forms of metamorphosis were as yet in existence: neither
butterflies, beetles, flies, nor bees. Manners were not gentle in those
epochs, which were full of the lust to destroy in order to produce; and
the Mantis, a feeble memory of those ancient ghosts, might well preserve
the customs of an earlier age. The utilisation of the males as food is a
custom in the case of other members of the Mantis family. It is, I must
admit, a general habit. The little grey Mantis, so small and looking so
harmless in her cage, which never seeks to harm her neighbours in spite
of her crowded quarters, falls upon her male and devours him as
ferociously as the Praying Mantis. I have worn myself out in trying to
procure the indispensable complements to my female specimens. No sooner
is my capture, strongly winged, vigorous and alert, introduced into the
cage than he is seized, more often than not, by one of the females who
no longer have need of his assistance and devoured. Once the ovaries are
satisfied the two species of Mantis conceive an antipathy for the male;
or rather they regard him merely as a particularly tasty species of
game.
CHAPTER VII
THE MANTIS.--THE NEST
Let us take a more pleasant aspect of the insect whose loves are so
tragic. Its nest is a marvel. In scientific language it is known as the
_ootek_, or the "egg-box." I shall not make use of this barbarous
expression. As one does not speak of the "egg-box" of the titmouse,
meaning "the nest of the titmouse," why should I invoke the box in
speaking of the Mantis? It may look more scientific; but that does not
interest me.
The nest of the Praying Mantis may be found almost everywhere in places
exposed to the sun: on stones, wood, vine stocks, the twigs of bushes,
stems of dried grass, and even on products of human industry, such as
fragments of brick, rags of heavy cloth, and pieces of old boots. Any
support will suffice, so long as it offers inequalities to which the
base of the nest may adhere, and so provide a solid foundation. The
usual dimensions of the nest are one and a half inches long by
three-quarters of an inch wide, or a trifle larger. The colour is a pale
tan, like that of a grain of wheat. Brought in contact with a flame the
nest burns readily, and emits an odour like that of burning silk. The
material of the nest is in fact a substance similar to silk, but instead
of being drawn into a thread it is allowed to harden while a mass of
spongy foam. If the nest is fixed on a branch the base creeps round it,
envelops the neighbouring twigs, and assumes a variable shape according
to the accidents of support; if it is fixed on a flat surface the under
side, which is always moulded by the support, is itself flat. The nest
then takes the form of a demi-ellipsoid, or, in other words, half an egg
cut longitudinally; more or less obtuse at one end, but pointed at the
other, and sometimes ending in a short curved tail.
In all cases the upper face is convex and regular. In it we can
distinguish three well-marked and longitudinal zones. The middle zone,
which is narrower than the others, is composed of thin plates arranged
in couples, and overlapping like the tiles of a roof. The edges of these
plates are free, leaving two parallel series of fissures by which the
young can issue when the eggs are hatched. In a nest recently abandoned
this zone is covered with fine cast-off skins which shiver at the least
breath, and soon disappear when exposed to the open air. I will call
this zone the zone of issue, as it is only along this bell that the
young can escape, being set free by those that have preceded them.
In all other directions the cradle of this numerous family presents an
unbroken wall. The two lateral zones, which occupy the greater part of
the demi-ellipsoid, have a perfect continuity of surface. The little
Mantes, which are very feeble when first hatched, could not possibly
make their way through the tenacious substance of the walls. On the
interior of these walls are a number of fine transverse furrows, signs
of the various layers in which the mass of eggs is disposed.
Let us cut the nest in half transversely. We shall then see that the
mass of eggs constitutes an elongated core, of very firm consistency,
surrounded as to the bottom and sides by a thick porous rind, like
solidified foam. Above the eggs are the curved plates, which are set
very closely and have little freedom; their edges constituting the zone
of issue, where they form a double series of small overlapping scales.
The eggs are set in a yellowish medium of horny appearance. They are
arranged in layers, in lines forming arcs of a circle, with the cephalic
extremities converging towards the zone of issue. This orientation tells
us of the method of delivery. The newly-born larvæ will slip into the
interval between two adjacent flaps or leaves, which form a prolongation
of the core; they will then find a narrow passage, none too easy to
effect, but sufficient, having regard to the curious provision which we
shall deal with directly; they will then reach the zone of issue. There,
under the overlapping scales, two passages of exit open for each layer
of eggs. Half the larvæ will issue by the right-hand passage, half by
that on the left hand. This process is repeated for each layer, from end
to end of the nest.
Let us sum up those structural details, which are not easily grasped
unless one has the nest before one. Lying along the axis of the nest,
and in shape like a date-stone, is the mass of eggs, grouped in layers.
A protective rind, a kind of solidified foam, envelops this core, except
at the top, along the central line, where the porous rind is replaced by
thin overlapping leaves. The free edges of these leaves form the
exterior of the zone of issue; they overlap one another, forming two
series of scales, leaving two exits, in the shape of narrow crevices,
for each layer of eggs.
[Illustration: 1. NEST OF THE PRAYING MANTIS.
2. TRANSVERSE SECTION OF THE SAME.
3, 3a. NEST OF EMPUSA PAUPERATA.
4. TRANSVERSE SECTION OF THE SAME.
5. VERTICAL SELECTION OF THE SAME.
6. NEST OF THE GREY MANTIS.
7. SCHEFFER'S SISYPHUS (see Chap. XII.)
8. PELLET OF THE SISYPHUS.
9. PELLET OF THE SISYPHUS WITH DEJECTA OF THE LARVA FORCED THROUGH THE
WALLS.]
To be present at the construction of the nest--to learn how the Mantis
contrives to build so complex a structure--such was the main point of my
researches. I succeeded, not without difficulty, as the eggs are laid
without warning and nearly always at night. After a great deal of futile
endeavour, chance at last favoured me. On the 5th of September one of my
guests, fecundated on the 29th of August, began to make her preparations
under my eyes, at four o'clock in the afternoon.
One remark before proceeding: all the nests I have obtained in the
laboratory--and I have obtained a good number--have without exception
been built upon the wire gauze of the covers. I have been careful to
provide the insects with roughened stones and tufts of thyme, both being
very commonly used as foundations in the open fields. The captives have
always preferred the network of wire gauze, which affords a perfectly
firm foundation, as the soft material of the nest becomes incrusted upon
the meshes as it hardens.
In natural conditions the nests are never in any way sheltered; they
support the inclemencies of winter, resist rain, wind, frost, and snow,
without becoming detached. It is true that the female always selects an
uneven support on which the foundations of the nest can be shaped, thus
obtaining a firm hold. The site chosen is always the best obtainable
within reach, and the wire gauze is constantly adopted as the best
foundation obtainable in the cages.
The only Mantis that I was able to observe at the moment of laying her
eggs worked upside-down, clinging to the wire near the top of the cover.
My presence, my magnifying-glass, my investigations did not disturb her
in the least, so absorbed was she in her labours. I was able to lift up
the dome of wire gauze, tilt it, reverse it, turn it over and reverse it
again, without causing the insect to delay her task for a moment. I was
able, with my tweezers, to raise the long wings in order to observe
rather more closely what was taking place beneath them; the Mantis took
absolutely no notice of me. So far all was well; the female did not
move, and lent herself impassively to all the indiscretions of the
observer. Nevertheless, matters did not proceed as I had wished, so
rapid was the operation and so difficult observation.
The end of the abdomen is constantly immersed in a blob of foam, which
does not allow one to grasp the details of the process very clearly.
This foam is of a greyish white, slightly viscous, and almost like
soapsuds. At the moment of its appearance it adheres slightly to the end
of a straw plunged into it. Two minutes later it is solidified and no
longer adheres to the straw. In a short time its consistency is that of
the substance of an old nest.
[Illustration: 1. THE MANTIS DEVOURING THE MALE IN THE ACT OF MATING.
2. THE MANTIS COMPLETING HER NEST.
3. GOLDEN SCARABÆI CUTTING UP A LOB-WORM.]
The foamy mass consists chiefly of air imprisoned in minute bubbles.
This air, which gives the nest a volume very much greater than that of
the abdomen of the Mantis, evidently does not issue from the insect
although the foam appears at the orifice of the genital organs; it is
borrowed from the atmosphere. The Mantis builds more especially with
air, which is eminently adapted to protect the nest against changes
of temperature. She emits a glutinous substance like the liquid
secretion of silk-worms, and with this composition, mixed
instantaneously with the outer air, she produces the foam of which the
nest is constructed.
She whips the secretion as we whip white of egg, in order to make it
rise and stiffen. The extremity of the abdomen opens in a long cleft,
forming two lateral ladles which open and shut with a rapid, incessant
movement, beating the viscous liquid and converting it into foam as it
is secreted. Beside the two oscillating ladles we see the internal
organs rising and falling, protruding and retreating like a piston-rod,
but it is impossible to observe the precise nature of their action,
bathed as they are in the opaque blob of foam.
The end of the abdomen, continually palpitating, rapidly closing and
opening its valves, oscillates right and left like a pendulum. From each
of these oscillations results a layer of eggs in the interior, and a
transversal crevice on the exterior. As it advances in the arc
described, suddenly, and at frequent intervals, it plunges deeper into
the foam, as though burying something at the bottom of the frothy mass.
Each time it does so an egg is doubtless deposited; but the operation is
so rapid, and takes place under conditions so unfavourable for
observation, that I have never once been enabled to see the oviduct at
work. I can only judge of the advent of the eggs by the movements of the
end of the abdomen, which is immersed more deeply with a sudden plunging
movement.
At the same time the viscous composition is emitted in intermittent
waves, and is beaten into a foam by the terminal valves. The foam thus
obtained spreads itself over the sides and at the base of the layer of
eggs, and projects through the meshes of the wire gauze as a result of
the pressure of the abdomen. Thus the spongy envelope is progressively
created as the ovaries are gradually emptied.
I imagine, although I cannot speak as the result of direct observation,
that for the central core, where the eggs are surrounded by a material
more homogeneous than that of the outer shell, the Mantis must employ
her secretion as it emerges, without beating it into a foam. The layer
of eggs once deposited, the two valves would produce the foam required
to envelop the eggs. It is extremely difficult, however, to guess what
occurs beneath the veil of foam-like secretion.
In a recent nest the zone of issue is surrounded by a layer of finely
porous matter, of a pure matt, almost chalky white, which contrasts
distinctly with the remainder of the nest, which is of a dirty white. It
resembles the icing composition made by confectioners with whipped white
of egg, sugar, and starch, for the ornamentation of cakes.
This snowy border is easily crumbled and easily detached. When it
disappears the zone of issue is clearly defined, with its double series
of leaves with free edges. Exposure to the weather, wind, and rain
result in its disappearance, fragment by fragment, so that old nests
preserve no trace of it.
At first sight one is tempted to regard this snowy substance as of a
different material to the rest of the nest. But does the Mantis really
employ two secretions? No. Anatomy, in the first place, assures us of
the unity of the materials of the nest. The organ which secretes the
substance of the nest consists of cylindrical tubes, having a curious
tangled appearance, which are arranged in two groups of twenty each.
They are all filled with a colourless, viscous fluid, which is precisely
similar in appearance in all parts of the organ. There is no indication
of any organ or secretion which could produce a chalky coloration.
Moreover, the method by which the snowy band is formed rejects the idea
of a different material. We see the two caudal appendices of the Mantis
sweeping the surface of the foamy mass, and skimming, so to speak, the
cream of the cream, gathering it together, and retaining it along the
hump of the nest in such a way as to form a band like a ribbon of icing.
What remains after this scouring process, or what oozes from the band
before it has set, spreads over the sides of the nest in a thin layer of
bubbles so fine that they cannot be distinguished without the aid of a
lens.
We often see a torrent of muddy water, full of clay in suspension,
covered with great streaks and masses of foam. On this fundamental foam,
so to call it, which is soiled with earthy matters, we see here and
there masses of a beautiful white foam, in which the bubbles are much
smaller. A process of selection results from variations in density, and
here and there we see foam white as snow resting on the dirty foam from
which it is produced. Something of the kind occurs when the Mantis
builds her nest. The two appendices whip the viscous secretion of the
glands into foam. The lightest portion, whose bubbles are of the
greatest tenuity, which is white on account of its finer porosity, rises
to the surface, where the caudal filaments sweep it up and gather it
into the snowy ribbon which runs along the summit of the nest.
So far, with a little patience, observation is possible and yields a
satisfactory result. It becomes impossible in the matter of the complex
central zone, where the exits for the larvæ are contrived through the
double series of overlapping leaves. The little I have been able to
learn amounts to this: The end of the abdomen, deeply cleft in a
horizontal direction, forms a kind of fork, of which the upper extremity
remains almost motionless, while the lower continuously oscillates,
producing the foam and depositing the eggs. The creation of the central
zone is certainly the work of the upper extremity.
It is always to be seen in the continuation of this central zone, in the
midst of the fine white foam gathered up by the caudal filaments. The
latter delimit the zone, one working on either side, feeling the edges
of the belt, and apparently testing it and judging its progress. These
two filaments are like two long fingers of exquisite sensitiveness,
which direct the difficult operation.
But how are the two series of scales obtained, and the fissures, the
gates of exit which they shelter? I do not know; I cannot even imagine.
I leave the end of the problem to others.
What a wonderful mechanism is this, that has the power to emit and to
form, so quickly and methodically, the horny medium of the central
kernel, the foam which forms the protective walls, the white creamy foam
of the ribbon which runs along the central zone, the eggs, and the
fecundating liquid, while at the same time it constructs the overlapping
leaves, the imbricated scales, and the alternating series of open
fissures! We are lost in the face of such a wonder. Yet how easily the
work is performed! Clinging to the wire gauze, forming, so to speak, the
axis of her nest, the Mantis barely moves. She bestows not a glance on
the marvel which is growing behind her; her limbs are used only for
support; they take no part in the building of the nest. The nest is
built, if we may say so, automatically. It is not the result of industry
and the cunning of instinct; it is a purely mechanical task, which is
conditioned by the implements, by the organisation of the insect. The
nest, complex though it is in structure, results solely from the
functioning of the organs, as in our human industries a host of objects
are mechanically fashioned whose perfection puts the dexterity of the
fingers to shame.
From another point of view the nest of the Mantis is even more
remarkable. It forms an excellent application of one of the most
valuable lessons of physical science in the matter of the conservation
of heat. The Mantis has outstripped humanity in her knowledge of thermic
nonconductors or insulators.
The famous physicist Rumford was responsible for a very pretty
experiment designed to demonstrate the low conductivity of air where
heat other than radiant heat is concerned. The famous scientist
surrounded a frozen cheese by a mass of foam consisting of well-beaten
eggs. The whole was exposed to the heat of an oven. In a few minutes a
light omelette was obtained, piping hot, but the cheese in the centre
was as cold as at the outset. The air imprisoned in the bubbles of the
surrounding froth accounts for the phenomenon. Extremely refractory to
heat, it had absorbed the heat of the oven and had prevented it from
reaching the frozen substance in the centre of the omelette.
Now, what does the Mantis do? Precisely what Rumford did; she whips her
albumen to obtain a soufflée, a froth composed of myriads of tiny
air-bubbles, which will protect the germs of life contained in the
central core. It is true that her aim is reversed; the coagulated foam
of the nest is a safeguard against cold, not against heat, but what will
afford protection from the one will afford protection from the other; so
that Rumford, had he wished, might equally well have maintained a hot
body at a high temperature in a refrigerator.
Rumford understood the athermic properties of a blanket of air-cells,
thanks to the accumulated knowledge of his predecessors and his own
studies and experiments. How is it that the Mantis, for who knows how
many ages, has been able to outstrip our physicists in this problem in
calorics? How did she learn to surround her eggs with this mass of
solidifying froth, so that it was able, although fixed to a bough or a
stone without other shelter, to brave with impunity the rigours of
winter?
The other Mantes found in my neighbourhood, which are the only species
of which I can speak with full knowledge, employ or omit the envelope of
solidifying froth accordingly as the eggs are or are not intended to
survive the winter. The little Grey Mantis (_Ameles decolor_), which
differs so widely from the Praying Mantis in that the wings of the
female are almost completely absent, builds a nest hardly as large as a
cherry-stone, and covers it skilfully with a porous rind. Why this
cellular envelope? Because the nest of the _Ameles_, like that of the
Praying Mantis, has to endure through the winter, fixed to a stone or a
twig, and is thus exposed to the full severity of the dangerous season.
The _Empusa pauperata_, on the other hand (one of the strangest of
European insects), builds a nest as small as that of the _Ameles_,
although the insect itself is as large as the Praying Mantis. This nest
is quite a small structure, composed of a small number of cells,
arranged side by side in three or four series, sloping together at the
neck. Here there is a complete absence of the porous envelope, although
the nest is exposed to the weather, like the previous examples, affixed
to some twig or fragment of rock. The lack of the insulating rind is a
sign of different climatic conditions. The eggs of the _Empusa_ hatch
shortly after they are laid, in warm and sunny weather. Not being
exposed to the asperities of the winter, they need no protection other
than the thin egg-cases themselves.
Are these nice and reasonable precautions, which rival the experiment of
Rumford, a fortuitous result?--one of the innumerable combinations which
fall from the urn of chance? If so, let us not recoil before the absurd:
let us allow that the blindness of chance is gifted with marvellous
foresight.
The Praying Mantis commences her nest at the blunter extremity, and
completes it at the pointed tail. The latter is often prolonged in a
sort of promontory, in which the insect expends the last drop of
glutinous liquid as she stretches herself after her task. A sitting of
two hours, more or less, without interruption, is required for the total
accomplishment of the work. Directly the period of labour is over, the
mother withdraws, indifferent henceforth to her completed task. I have
watched her, half expecting to see her return, to discover some
tenderness for the cradle of her family. But no: not a trace of maternal
pleasure. The work is done, and concerns her no longer. Crickets
approach; one of them even squats upon the nest. The Mantis takes no
notice of them. They are peaceful intruders, to be sure; but even were
they dangerous, did they threaten to rifle the nest, would she attack
them and drive them away? Her impassive demeanour convinces me that she
would not. What is the nest to her? She is no longer conscious of it.
I have spoken of the many embraces to which the Praying Mantis submits,
and of the tragic end of the male, who is almost invariably devoured as
though a lawful prey. In the space of a fortnight I have known the same
female to adventure upon matrimony no less than seven times. Each time
the readily consoled widow devoured her mate. Such habits point to
frequent laying; and we find the appearance confirmed, though not as a
general rule. Some of my females gave me one nest only; others two, the
second as capacious as the first. The most fruitful of all produced
three; of these the two first were of normal dimensions, while the third
was about half the usual size.
From this we can reckon the productivity of the insect's ovaries. From
the transverse fissures of the median zone of the nest it is easy to
estimate the layers of eggs; but these layers contain more or fewer eggs
according to their position in the middle of the nest or near the ends.
The numbers contained by the widest and narrowest layers will give us
an approximate average. I find that a nest of fair size contains about
four hundred eggs. Thus the maker of the three nests, of which the last
was half as large as the others, produced no less than a thousand eggs;
eight hundred were deposited in the larger nests and two or three
hundred in the smaller. Truly a fine family, but a thought ungainly,
were it not that only a few of its members can survive.
Of a fair size, of curious structure, and well in evidence on its twig
or stone, the nest of the Praying Mantis could hardly escape the
attention of the Provençal peasant. It is well known in the country
districts, where it goes by the name of _tigno_; it even enjoys a
certain celebrity. But no one seems to be aware of its origin. It is
always a surprise to my rustic neighbours when they learn that the
well-known _tigno_ is the nest of the common Mantis, the _Prègo-Diéu_.
This ignorance may well proceed from the nocturnal habits of the Mantis.
No one has caught the insect at work upon her nest in the silence of the
night. The link between the artificer and the work is missing, although
both are well known to the villager.
No matter: the singular object exists; it catches the eye, it attracts
attention. It must therefore be good for something; it must possess
virtue of some kind. So in all ages have the simple reasoned, in the
childlike hope of finding in the unfamiliar an alleviation of their
sorrows.
By general agreement the rural pharmacopoeia of Provence pronounces
the _tigno_ to be the best of remedies against chilblains. The method of
employment is of the simplest. The nest is cut in two, squeezed and the
affected part is rubbed with the cut surface as the juices flow from
it. This specific, I am told, is sovereign. All sufferers from blue and
swollen fingers should without fail, according to traditional usage,
have recourse to the _tigno_.
Is it really efficacious? Despite the general belief, I venture to doubt
it, after fruitless experiments on my own fingers and those of other
members of my household during the winter of 1895, when the severe and
persistent cold produced an abundant crop of chilblains. None of us,
treated with the celebrated unguent, observed the swelling to diminish;
none of us found that the pain and discomfort was in the least assuaged
by the sticky varnish formed by the juices of the crushed _tigno_. It is
not easy to believe that others are more successful, but the popular
renown of the specific survives in spite of all, probably thanks to a
simple accident of identity between the name of the remedy and that of
the infirmity: the Provençal for "chilblain" is _tigno_. From the moment
when the chilblain and the nest of the Mantis were known by the same
name were not the virtues of the latter obvious? So are reputations
created.
In my own village, and doubtless to some extent throughout the Midi, the
_tigno_--the nest of the Mantis, not the chilblain--is also reputed as a
marvellous cure for toothache. It is enough to carry it upon the person
to be free of that lamentable affection. Women wise in such matters
gather them beneath a propitious moon, and preserve them piously in some
corner of the clothes-press or wardrobe. They sew them in the lining of
the pocket, lest they should be pulled out with the handkerchief and
lost; they will grant the loan of them to a neighbour tormented by some
refractory molar. "Lend me thy _tigno_: I am suffering martyrdom!" begs
the owner of a swollen face.--"Don't on any account lose it!" says the
lender: "I haven't another, and we aren't at the right time of moon!"
We will not laugh at the credulous victim; many a remedy triumphantly
puffed on the latter pages of the newspapers and magazines is no more
effectual. Moreover, this rural simplicity is surpassed by certain old
books which form the tomb of the science of a past age. An English
naturalist of the sixteenth century, the well-known physician, Thomas
Moffat, informs us that children lost in the country would inquire their
way of the Mantis. The insect consulted would extend a limb, indicating
the direction to be taken, and, says the author, scarcely ever was the
insect mistaken. This pretty story is told in Latin, with an adorable
simplicity.
CHAPTER VIII
THE GOLDEN GARDENER.--ITS NUTRIMENT
In writing the first lines of this chapter I am reminded of the
slaughter-pens of Chicago; of those horrible meat factories which in the
course of the year cut up one million and eighty thousand bullocks and
seventeen hundred thousand swine, which enter a train of machinery alive
and issue transformed into cans of preserved meat, sausages, lard, and
rolled hams. I am reminded of these establishments because the beetle I
am about to speak of will show us a compatible celerity of butchery.
In a spacious, glazed insectorium I have twenty-five Carabi aurati. At
present they are motionless, lying beneath a piece of board which I gave
them for shelter. Their bellies cooled by the sand, their backs warmed
by the board, which is visited by the sun, they slumber and digest their
food. By good luck I chance upon a procession of pine-caterpillars, in
process of descending from their tree in search of a spot suitable for
burial, the prelude to the phase of the subterranean chrysalis. Here is
an excellent flock for the slaughter-house of the Carabi.
I capture them and place them in the insectorium. The procession is
quickly re-formed; the caterpillars, to the number of perhaps a hundred
and fifty, move forward in an undulating line. They pass near the piece
of board, one following the other like the pigs at Chicago. The moment
is propitious. I cry Havoc! and let loose the dogs of war: that is to
say, I remove the plank.
The sleepers immediately awake, scenting the abundant prey. One of them
runs forward; three, four, follow; the whole assembly is aroused; those
who are buried emerge; the whole band of cut-throats falls upon the
passing flock. It is a sight never to be forgotten. The mandibles of the
beetles are at work in all directions; the procession is attacked in the
van, in the rear, in the centre; the victims are wounded on the back or
the belly at random. The furry skins are gaping with wounds; their
contents escape in knots of entrails, bright green with their aliment,
the needles of the pine-tree; the caterpillars writhe, struggling with
loop-like movements, gripping the sand with their feet, dribbling and
gnashing their mandibles. Those as yet unwounded are digging desperately
in the attempt to take refuge underground. Not one succeeds. They are
scarcely half buried before some beetle runs to them and destroys them
by an eviscerating wound.
If this massacre did not occur in a dumb world we should hear all the
horrible tumult of the slaughter-houses of Chicago. But only the ear of
the mind can hear the shrieks and lamentations of the eviscerated
victims. For myself, I possess this ear, and am full of remorse for
having provoked such sufferings.
Now the beetles are rummaging in all directions through the heap of
dead and dying, each tugging and tearing at a morsel which he carries
off to swallow in peace, away from the inquisitive eyes of his fellows.
This mouthful disposed of, another is hastily cut from the body of some
victim, and the process is repeated so long as there are bodies left. In
a few minutes the procession is reduced to a few shreds of still
palpitating flesh.
There were a hundred and fifty caterpillars; the butchers were
twenty-five. This amounts to six victims dispatched by each beetle. If
the insect had nothing to do but to kill, like the knackers in the meat
factories, and if the staff numbered a hundred--a very modest figure as
compared with the staff of a lard or bacon factory--then the total
number of victims, in a day of ten hours, would be thirty-six thousand.
No Chicago "cannery" ever rivalled such a result.
The speed of assassination is the more remarkable when we consider the
difficulties of attack. The beetle has no endless chain to seize its
victim by one leg, hoist it up, and swing it along to the butcher's
knife; it has no sliding plank to hold the victim's head beneath the
pole-axe of the knacker; it has to fall upon its prey, overpower it, and
avoid its feet and its mandibles. Moreover, the beetle eats its prey on
the spot as it kills. What slaughter there would be if the insect
confined itself to killing!
What do we learn from the slaughter-houses of Chicago and the fate of
the beetle's victims? This: That the man of elevated morality is so far
a very rare exception. Under the skin of the civilised being there lurks
almost always the ancestor, the savage contemporary of the cave-bear.
True humanity does not yet exist; it is growing, little by little,
created by the ferment of the centuries and the dictates of conscience;
but it progresses towards the highest with heartbreaking slowness.
It was only yesterday that slavery finally disappeared: the basis of the
ancient social organism; only yesterday was it realised that man, even
though black, is really man and deserves to be treated accordingly.
What formerly was woman? She was what she is to-day in the East: a
gentle animal without a soul. The question was long discussed by the
learned. The great divine of the seventeenth century, Bossuet himself,
regarded woman as the diminutive of man. The proof was in the origin of
Eve: she was the superfluous bone, the thirteenth rib which Adam
possessed in the beginning. It has at last been admitted that woman
possesses a soul like our own, but even superior in tenderness and
devotion. She has been allowed to educate herself, which she has done at
least as zealously as her coadjutor. But the law, that gloomy cavern
which is still the lurking-place of so many barbarities, continues to
regard her as an incapable and a minor. The law in turn will finally
surrender to the truth.
The abolition of slavery and the education of woman: these are two
enormous strides upon the path of moral progress. Our descendants will
go farther. They will see, with a lucidity capable of piercing every
obstacle, that war is the most hopeless of all absurdities. That our
conquerors, victors of battles and destroyers of nations, are detestable
scourges; that a clasp of the hand is preferable to a rifle-shot; that
the happiest people is not that which possesses the largest battalions,
but that which labours in peace and produces abundantly; and that the
amenities of existence do not necessitate the existence of frontiers,
beyond which we meet with all the annoyances of the custom-house, with
its officials who search our pockets and rifle our luggage.
Our descendants will see this and many other marvels which to-day are
extravagant dreams. To what ideal height will the process of evolution
lead mankind? To no very magnificent height, it is to be feared. We are
afflicted by an indelible taint, a kind of original sin, if we may call
sin a state of things with which our will has nothing to do. We are made
after a certain pattern and we can do nothing to change ourselves. We
are marked with the mark of the beast, the taint of the belly, the
inexhaustible source of bestiality.
The intestine rules the world. In the midst of our most serious affairs
there intrudes the imperious question of bread and butter. So long as
there are stomachs to digest--and as yet we are unable to dispense with
them--we must find the wherewithal to fill them, and the powerful will
live by the sufferings of the weak. Life is a void that only death can
fill. Hence the endless butchery by which man nourishes himself, no less
than beetles and other creatures; hence the perpetual holocausts which
make of this earth a knacker's yard, beside which the slaughter-houses
of Chicago are as nothing.
But the feasters are legion, and the feast is not abundant in
proportion. Those that have not are envious of those that have; the
hungry bare their teeth at the satisfied. Then follows the battle for
the right of possession. Man raises armies; to defend his harvests, his
granaries, and his cellars, he resorts to warfare. When shall we see the
end of it? Alas, and many times alas! As long as there are wolves in the
world there must be watch-dogs to defend the flock.
This train of thought has led us far away from our beetles. Let us
return to them. What was my motive in provoking the massacre of this
peaceful procession of caterpillars who were on the point of self-burial
when I gave them over to the butchers? Was it to enjoy the spectacle of
a frenzied massacre? By no means; I have always pitied the sufferings of
animals, and the smallest life is worthy of respect. To overcome this
pity there needed the exigencies of scientific research--exigencies
which are often cruel.
In this case the subject of research was the habits of the Carabus
auratus, the little vermin-killer of our gardens, who is therefore
vulgarly known as the Gardener Beetle. How far is this title deserved?
What game does the Gardener Beetle hunt? From what vermin does he free
our beds and borders? His dealings with the procession of
pine-caterpillars promise much. Let us continue our inquiry.
On various occasions about the end of April the gardens afford me the
sight of such processions, sometimes longer, sometimes shorter. I
capture them and place them in the vivarium. Bloodshed commences the
moment the banquet is served. The caterpillars are eviscerated; each by
a single beetle, or by several simultaneously. In less than fifteen
minutes the flock is completely exterminated. Nothing remains but a few
shapeless fragments, which are carried hither and thither, to be
consumed at leisure under the shelter of the wooden board. One well-fed
beetle decamps, his booty in his jaws, hoping to finish his feast in
peace. He is met by companions who are attracted by the morsel hanging
from the mandibles of the fugitive, and audaciously attempt to rob him.
First two, then three, they all endeavour to deprive the legitimate
owner of his prize. Each seizes the fragment, tugs at it, commences to
swallow it without further ado. There is no actual battle; no violent
assaults, as in the case of dogs disputing a bone. Their efforts are
confined to the attempted theft. If the legitimate owner retains his
hold they consume his booty in common, mandibles to mandibles, until the
fragment is torn or bitten through, and each retires with his mouthful.
As I found to my cost in bygone experiments, the pine-caterpillar wields
a violently corrosive poison, which produces a painful rash upon the
hands. It must therefore, one would think, form a somewhat highly
seasoned diet. The beetles, however, delight in it. No matter how many
flocks I provide them with, they are all consumed. But no one, that I
know of, has ever found the Golden Gardener and its larva in the silken
cocoons of the Bombyx. I do not expect ever to make such a discovery.
These cocoons are inhabited only in winter, when the Gardener is
indifferent to food, and lies torpid in the earth. In April, however,
when the processions of larvæ are seeking a suitable site for burial and
metamorphosis, the Gardener should profit largely by its good fortune
should it by any chance encounter them.
The furry nature of the victim does not in the least incommode the
beetle; but the hairiest of all our caterpillars, the Hedgehog
Caterpillar, with its undulating mane, partly red and partly black, does
seem to be too much for the beetle. Day after day it wanders about the
vivarium in company with the assassins. The latter apparently ignore its
presence. From time to time one of them will halt, stroll round the
hairy creature, examine it, and try to penetrate the tangled fleece.
Immediately repulsed by the long, dense palisade of hairs, he retires
without inflicting a wound, and the caterpillar proceeds upon its way
with undulating mane, in pride and security.
But this state of things cannot last. In a hungry moment, emboldened
moreover by the presence of his fellows, the cowardly creature decides
upon a serious attack. There are four of them; they industriously attack
the caterpillar, which finally succumbs, assaulted before and behind. It
is eviscerated and swallowed as greedily as though it were a defenceless
grub.
According to the hazard of discovery, I provision my menagerie with
various caterpillars, some smooth and others hairy. All are accepted
with the utmost eagerness, so long as they are of average size as
compared with the beetles themselves. If too small they are despised, as
they would not yield a sufficient mouthful. If they are too large the
beetle is unable to handle them. The caterpillars of the Sphinx moth and
the Great Peacock moth, for example, would fall an easy prey to the
beetle were it not that at the first bite of the assailant the intended
victim, by a contortion of its powerful flanks, sends the former
flying. After several attacks, all of which end by the beetle being
flung back to some considerable distance, the insect regretfully
abandons his prey. I have kept two strong and lively caterpillars for a
fortnight in the cage of my golden beetles, and nothing more serious
occurred. The trick of the suddenly extended posterior was too much for
the ferocious mandibles.
The chief utility of the Golden Gardener lies in its extermination of
all caterpillars that are not too powerful to attack. It has one
limitation, however: it is not a climber. It hunts on the ground; never
in the foliage overhead. I have never seen it exploring the twigs of
even the smallest of bushes. When caged it pays no attention to the most
enticing caterpillars if the latter take refuge in a tuft of thyme, at a
few inches above the ground. This is a great pity. If only the beetle
could climb how rapidly three or four would rid our cabbages of that
grievous pest, the larva of the white cabbage butterfly! Alas! the best
have always some failing, some vice.
To exterminate caterpillars: that is the true vocation of the Golden
Gardener. It is annoying that it can give us but little or no assistance
in ridding us of another plague of the kitchen-garden: the snail. The
slime of the snail is offensive to the beetle; it is safe from the
latter unless crippled, half crushed, or projecting from the shell. Its
relatives, however, do not share this dislike. The horny Procrustes, the
great Scarabicus, entirely black and larger than the Carabus, attacks
the snail most valiantly, and empties its shell to the bottom, in spite
of the desperate secretion of slime. It is a pity that the Procrustes is
not more frequently found in our gardens; it would be an excellent
gardener's assistant.
CHAPTER IX
THE GOLDEN GARDENER--COURTSHIP
It is generally recognized that the Carabus auratus is an active
exterminator of caterpillars; on this account in particular it deserves
its title of Gardener Beetle; it is the vigilant policeman of our
kitchen-gardens, our flower-beds and herbaceous borders. If my inquiries
add nothing to its established reputation in this respect, they will
nevertheless, in the following pages, show the insect in a light as yet
unsuspected. The ferocious beast of prey, the ogre who devours all
creatures that are not too strong for him, is himself killed and eaten:
by his fellows, and by many others.
Standing one day in the shadow of the plane-trees that grow before my
door, I see a Golden Gardener go by as if on pressing business. The
pilgrim is well met; he will go to swell the contents of my vivarium. In
capturing him I notice that the extremities of the wing-covers are
slightly damaged. Is this the result of a struggle between rivals? There
is nothing to tell me. The essential thing is that the insect should not
be handicapped by any serious injury. Inspected, and found to be without
any serious wound and fit for service, it is introduced into the glass
dwelling of its twenty-five future companions.
Next day I look for the new inmate. It is dead. Its comrades have
attacked it during the night and have cleaned out its abdomen,
insufficiently protected by the damaged wing-covers. The operation has
been performed very cleanly, without any dismemberment. Claws, head,
corselet, all are correctly in place; the abdomen only has a gaping
wound through which its contents have been removed. What remains is a
kind of golden shell, formed of the two conjoined elytra. The shell of
an oyster emptied of its inmate is not more empty.
This result astonishes me, for I have taken good care that the cage
should never be long without food. The snail, the pine-cockchafer, the
Praying Mantis, the lob-worm, the caterpillar, and other favourite
insects, have all been given in alternation and in sufficient
quantities. In devouring a brother whose damaged armour lent itself to
any easy attack my beetles had not the excuse of hunger.
Is it their custom to kill the wounded and to eviscerate such of their
fellows as suffer damage? Pity is unknown among insects. At the sight of
the desperate struggles of a crippled fellow-creature none of the same
family will cry a halt, none will attempt to come to its aid. Among the
carnivorous insects the matter may develop to a tragic termination. With
them, the passers-by will often run to the cripple. But do they do so in
order to help it? By no means: merely to taste its flesh, and, if they
find it agreeable, to perform the most radical cure of its ills by
devouring it.
It is possible, therefore, that the Gardener with the injured
wing-covers had tempted his fellows by the sight of his imperfectly
covered back. They saw in their defenceless comrade a permissible
subject for dissection. But do they respect one another when there is no
previous wound? At first there was every appearance that their relations
were perfectly pacific. During their sanguinary meals there is never a
scuffle between the feasters; nothing but mere mouth-to-mouth thefts.
There are no quarrels during the long siestas in the shelter of the
board. Half buried in the cool earth, my twenty-five subjects slumber
and digest their food in peace; they lie sociably near one another, each
in his little trench. If I raise the plank they awake and are off,
running hither and thither, constantly encountering one another without
hostilities.
The profoundest peace is reigning, and to all appearances will last for
ever, when in the early days of June I find a dead Gardener. Its limbs
are intact; it is reduced to the condition of a mere golden husk; like
the defenceless beetle I have already spoken of, it is as empty as an
oyster-shell. Let us examine the remains. All is intact, save the huge
breach in the abdomen. So the insect was sound and unhurt when the
others attacked it.
A few days pass, and another Gardener is killed and dealt with as
before, with no disorder in the component pieces of its armour. Let us
place the dead insect on its belly; it is to all appearances untouched.
Place it on its back; it is hollow, and has no trace of flesh left
beneath its carapace. A little later, and I find another empty relic;
then another, and yet another, until the population of my menagerie is
rapidly shrinking. If this insensate massacre continues I shall soon
find my cage depopulated.
Are my beetles hoary with age? Do they die a natural death, and do the
survivors then clean out the bodies? Or is the population being reduced
at the expense of sound and healthy insects? It is not easy to elucidate
the matter, since the atrocities are commonly perpetrated in the night.
But, finally, with vigilance, on two occasions, I surprise the beetles
at their work in the light of day.
Towards the middle of June a female attacks a male before my eyes. The
male is recognisable by his slightly smaller size. The operation
commences. Raising the ends of the wing-covers, the assailant seizes her
victim by the extremity of the abdomen, from the dorsal side. She pulls
at him furiously, eagerly munching with her mandibles. The victim, who
is in the prime of life, does not defend himself, nor turn upon his
assailant. He pulls his hardest in the opposite direction to free
himself from those terrible fangs; he advances and recoils as he is
overpowered by or overpowers the assassin; and there his resistance
ends. The struggle lasts a quarter of an hour. Other beetles, passing
by, call a halt, and seem to say "My turn next!" Finally, redoubling his
efforts, the male frees himself and flies. If he had not succeeded in
escaping the ferocious female would undoubtedly have eviscerated him.
[Illustration: THE GOLDEN GARDENER: THE MATING SEASON OVER, THE MALES
ARE EVISCERATED BY THE FEMALES.]
A few days later I witness a similar scene, but this time the tragedy is
played to the end. Once more it is a female who seizes a male from
behind. With no other protest except his futile efforts to escape, the
victim is forced to submit. The skin finally yields; the wound
enlarges, and the viscera are removed and devoured by the matron, who
empties the carapace, her head buried in the body of her late companion.
The legs of the miserable victim tremble, announcing the end. The
murderess takes no notice; she continues to rummage as far as she can
reach for the narrowing of the thorax. Nothing is left but the closed
boat-shaped wing-covers and the fore parts of the body. The empty shell
is left lying on the scene of the tragedy.
In this way must have perished the beetles--always males--whose remains
I find in the cage from time to time; thus the survivors also will
perish. Between the middle of June and the 1st of August the inhabitants
of the cage, twenty-five in number at the outset, are reduced to five,
all of whom are females. All the males, to the number of twenty, have
disappeared, eviscerated and completely emptied. And by whom? Apparently
by the females.
That this is the case is attested in the first place by the two assaults
of which I was perchance the witness; on two occasions, in broad
daylight, I saw the female devouring the male, having opened the abdomen
under the wing-covers, or having at least attempted to do so. As for the
rest of the massacres, although direct observation was lacking, I had
one very valuable piece of evidence. As we have seen, the victim does
not retaliate, does not defend himself, but simply tries to escape by
pulling himself away.
If it were a matter of an ordinary fight, a conflict such as might arise
in the struggle for life, the creature attacked would obviously
retaliate, since he is perfectly well able to do so; in an ordinary
conflict he would meet force by force, and return bite for bite. His
strength would enable him to come well out of a struggle, but the
foolish creature allows himself to be devoured without retaliating. It
seems as though an invincible repugnance prevents him from offering
resistance and in turn devouring the devourer. This tolerance reminds
one of the scorpion of Languedoc, which on the termination of the
hymeneal rites allows the female to devour him without attempting to
employ his weapon, the venomous dagger which would form a formidable
defence; it reminds us also of the male of the Praying Mantis, which
still embraces the female though reduced to a headless trunk, while the
latter devours him by small mouthfuls, with no rebellion or defence on
his part. There are other examples of hymeneal rites to which the male
offers no resistance.
The males of my menagerie of Gardeners, one and all eviscerated, speak
of similar customs. They are the victims of the females when the latter
have no further use for them. For four months, from April to August, the
insects pair off continually; sometimes tentatively, but usually the
mating is effective. The business of mating is all but endless for these
fiery spirits.
The Gardener is prompt and businesslike in his affairs of the heart. In
the midst of the crowd, with no preliminary courtship, the male throws
himself upon the female. The female thus embraced raises her head a
trifle as a sign of acquiescence, while the cavalier beats the back of
her neck with his antennæ. The embrace is brief, and they abruptly
separate; after a little refreshment the two parties are ready for other
adventures, and yet others, so long as there are males available. After
the feast, a brief and primitive wooing; after the wooing, the feast; in
such delights the life of the Gardener passes.
The females of my collection were in no proper ratio to the number of
aspiring lovers; there were five females to twenty males. No matter;
there was no rivalry, no hustling; all went peacefully and sooner or
later each was satisfied.
I should have preferred a better proportioned assembly. Chance, not
choice, had given me that at my disposal. In the early spring I had
collected all the Gardeners I could find under the stones of the
neighbourhood, without distinguishing the sexes, for they are not easy
to recognise merely by external characteristics. Later on I learned by
watching them that a slight excess of size was the distinctive sign of
the female. My menagerie, so ill-proportioned in the matter of sex, was
therefore the result of chance. I do not suppose this preponderance of
males exists in natural conditions. On the other hand, one never sees
such numerous groups at liberty, in the shelter of the same stone. The
Gardener lives an almost solitary life; it is rarely that one finds two
or three beneath the same object of shelter. The gathering in my
menagerie was thus exceptional, although it did not lead to confusion.
There is plenty of room in the glass cage for excursions to a distance
and for all their habitual manoeuvres. Those who wish for solitude can
obtain it; those who wish for company need not seek it.
For the rest, captivity cannot lie heavily on them; that is proved by
their frequent feasts, their constant mating. They could not thrive
better in the open; perhaps not so well, for food is less abundant under
natural conditions. In the matter of well-being the prisoners are in a
normal condition, favourable to the maintenance of their usual habits.
It is true that encounters of beetle with beetle are more frequent here
than in the open. Hence, no doubt, arise more opportunities for the
females to persecute the males whom they no longer require; to fall upon
them from the rear and eviscerate them. This pursuit of their onetime
lovers is aggravated by their confined quarters; but it certainly is not
caused thereby, for such customs are not suddenly originated.
The mating season over, the female encountering a male in the open must
evidently regard him as fair game, and devour him as the termination of
the matrimonial rites. I have turned over many stones, but have never
chanced upon this spectacle, but what has occurred in my menagerie is
sufficient to convince me. What a world these beetles live in, where the
matron devours her mate so soon as her fertility delivers her from the
need of him! And how lightly the males must be regarded by custom, to be
served in this manner!
Is this practice of post-matrimonial cannibalism a general custom in the
insect world? For the moment, I can recollect only three characteristic
examples: those of the Praying Mantis, the Golden Gardener, and the
scorpion of Languedoc. An analogous yet less brutal practice--for the
victim is defunct before he is eaten--is a characteristic of the Locust
family. The female of the white-faced Decticus will eagerly devour the
body of her dead mate, as will the Green Grasshopper.
To a certain extent this custom is excused by the nature of the insect's
diet; the Decticus and the Grasshopper are essentially carnivorous.
Encountering a dead body of their own species, a female will devour it,
even if it be the body of her latest mate.
But what are we to say in palliation of the vegetarians? At the approach
of the breeding season, before the eggs are laid, the Ephippigera turns
upon her still living mate, disembowels him, and eats as much of him as
her appetite will allow.
The cheerful Cricket shows herself in a new light at this season; she
attacks the mate who lately wooed her with such impassioned serenades;
she tears his wings, breaks his musical thighs, and even swallows a few
mouthfuls of the instrumentalist. It is probable that this deadly
aversion of the female for the male at the end of the mating season is
fairly common, especially among the carnivorous insects. But what is the
object of this atrocious custom? That is a question I shall not fail to
answer when circumstances permit.
CHAPTER X
THE FIELD-CRICKET
The breeding of Crickets demands no particular preparations. A little
patience is enough--patience, which according to Buffon is genius; but
which I, more modestly, will call the superlative virtue of the
observer. In April, May, or later we may establish isolated couples in
ordinary flower-pots containing a layer of beaten earth. Their diet will
consist of a leaf of lettuce renewed from time to time. The pot must be
covered with a square of glass to prevent the escape of the inmates.
I have gathered some very curious data from these makeshift appliances,
which may be used with and as a substitute for the cages of wire gauze,
although the latter are preferable. We shall return to the point
presently. For the moment let us watch the process of breeding, taking
care that the critical hour does not escape us.
It was during the first week of June that my assiduous visits were at
last repaid. I surprised the female motionless, with the oviduct planted
vertically in the soil. Heedless of the indiscreet visitor, she remained
for a long time stationed at the same point. Finally she withdrew her
oviduct, and effaced, though without particular care, the traces of the
hole in which her eggs were deposited, rested for a moment, walked
away, and repeated the operation; not once, but many times, first here,
then there, all over the area at her disposal. Her behaviour was
precisely the same as that of the Decticus, except that her movements
were more deliberate. At the end of twenty-four hours her eggs were
apparently all laid. For greater certainty I waited a couple of days
longer.
I then examined the earth in the pot. The eggs, of a straw-yellow, are
cylindrical in form, with rounded ends, and measure about one-tenth of
an inch in length. They are placed singly in the soil, in a
perpendicular position.
I have found them over the whole area of the pot, at a depth of a
twelfth of an inch. As closely as the difficulties of the operation will
allow, I have estimated the eggs of a single female, upon passing the
earth through a sieve, at five or six hundred. Such a family will
certainly undergo an energetic pruning before very long.
The egg of the Cricket is a curiosity, a tiny mechanical marvel. After
hatching it appears as a sheath of opaque white, open at the summit,
where there is a round and very regular aperture, to the edge of which
adheres a little valve like a skull-cap which forms the lid. Instead of
breaking at random under the thrusts or the cuts of the new-formed
larva, it opens of itself along a line of least resistance which occurs
expressly for the purpose. The curious process of the actual hatching
should be observed.
A fortnight after the egg is laid two large eye-marks, round and of a
reddish black, are seen to darken the forward extremity of the egg.
Next, a little above these two points, and right at the end of the
cylinder, a tiny circular capsule or swelling is seen. This marks the
line of rupture, which is now preparing. Presently the translucency of
the egg allows us to observe the fine segmentation of the tiny inmate.
Now is the moment to redouble our vigilance and to multiply our visits,
especially during the earlier part of the day.
Fortune favours the patient, and rewards my assiduity Round the little
capsule changes of infinite delicacy have prepared the line of least
resistance. The end of the egg, pushed by the head of the inmate,
becomes detached, rises, and falls aside like the top of a tiny phial.
The Cricket issues like a Jack-in-the-box.
When the Cricket has departed the shell remains distended, smooth,
intact, of the purest white, with the circular lid hanging to the mouth
of the door of exit. The egg of the bird breaks clumsily under the blows
of a wart-like excrescence which is formed expressly upon the beak of
the unborn bird; the egg of the Cricket, of a far superior structure,
opens like an ivory casket. The pressure of the inmate's head is
sufficient to work the hinge.
The moment he is deprived of his white tunic, the young Cricket, pale
all over, almost white, begins to struggle against the overlying soil.
He strikes it with his mandibles; he sweeps it aside, kicking it
backwards and downwards; and being of a powdery quality, which offers no
particular resistance, he soon arrives at the surface, and henceforth
knows the joys of the sun, and the perils of intercourse with the
living; a tiny, feeble creature, little larger than a flea. His colour
deepens. In twenty-four hours he assumes a splendid ebony black which
rivals that of the adult insect. Of his original pallor he retains only
a white girdle which encircles the thorax and reminds one of the
leading-string of an infant.
Very much on the alert, he sounds his surroundings with his long
vibrating antennæ; he toddles and leaps along with a vigour which his
future obesity will no longer permit.
This is the age of stomach troubles. What are we to give him to eat? I
do not know. I offer him adult diet--the tender leaves of a lettuce. He
disdains to bite it; or perhaps his bites escape me, so tiny would they
be.
In a few days, what with my ten households, I see myself loaded with
family cares. What shall I do with my five or six thousand Crickets, an
attractive flock, to be sure, but one I cannot bring up in my ignorance
of the treatment required? I will give you liberty, gentle creatures! I
will confide you to the sovereign nurse and schoolmistress, Nature!
It is done. Here and there about my orchard, in the most favourable
localities, I loose my legions. What a concert I shall have before my
door next year if all goes well! But no! There will probably be silence,
for the terrible extermination will follow which corresponds with the
fertility of the mother. A few couples only may survive: that is the
most we can hope.
The first to come to the living feast and the most eager at the
slaughter are the little grey lizard and the ant. I am afraid this
latter, hateful filibuster that it is, will not leave me a single
Cricket in my garden. It falls upon the tiny Crickets, eviscerates them,
and devours them with frantic greed.
Satanic creature! And to think that we place it in the front rank of
the insect world! The books celebrate its virtues and never tire of its
praises; the naturalists hold it in high esteem and add to its
reputation daily; so true is it of animals, as of man, that of the
various means of living in history the most certain is to do harm to
others.
Every one knows the _Bousier_ (dung-beetle) and the Necrophorus, those
lively murderers; the gnat, the drinker of blood; the wasp, the
irascible bully with the poisoned dagger; and the ant, the maleficent
creature which in the villages of the South of France saps and imperils
the rafters and ceilings of a dwelling with the same energy it brings to
the eating of a fig. I need say no more; human history is full of
similar examples of the useful misunderstood and undervalued and the
calamitous glorified.
What with the ants and other exterminating forces, the massacre was so
great that the colonies of Crickets in my orchard, so numerous at the
outset, were so far decimated that I could not continue my observations,
but had to resort to the outside world for further information.
In August, among the detritus of decaying leaves, in little oases whose
turf is not burned by the sun, I find the young Cricket has already
grown to a considerable size; he is all black, like the adult, without a
vestige of the white cincture of the early days. He has no domicile. The
shelter of a dead leaf, the cover afforded by a flat stone is
sufficient; he is a nomad, and careless where he takes his repose.
[Illustration: 1. THE FIELD-CRICKET. A DUEL BETWEEN RIVALS.
2. THE FIELD-CRICKET. THE DEFEATED RIVAL RETIRES, INSULTED BY THE
VICTOR.]
Not until the end of October, when the first frosts are at hand, does
the work of burrowing commence. The operation is very simple, as far as
I can tell from what I have learned from the insect in captivity. The
burrow is never made at a bare or conspicuous point; it is always
commenced under the shelter of a faded leaf of lettuce, the remains of
the food provided. This takes the place of the curtain of grass so
necessary to preserve the mysterious privacy of the establishment.
The little miner scratches with his fore-claws, but also makes use of
the pincers of his mandibles in order to remove pieces of grit or gravel
of any size. I see him stamping with his powerful hinder limbs, which
are provided with a double row of spines; I see him raking and sweeping
backwards the excavated material, and spreading it out in an inclined
plane. This is his whole method.
At first the work goes forward merrily. The excavator disappears under
the easily excavated soil of his prison after two hours' labour. At
intervals he returns to the orifice, always tail first, and always
raking and sweeping. If fatigue overcomes him he rests on the threshold
of his burrow, his head projecting outwards, his antennæ gently
vibrating. Presently he re-enters his tunnel and sets to work again with
his pincers and rakes. Presently his periods of repose grow longer and
tire my patience.
The most important part of the work is now completed. Once the burrow
has attained a depth of a couple of inches, it forms a sufficient
shelter for the needs of the moment. The rest will be the work of time;
a labour resumed at will, for a short time daily. The burrow will be
made deeper and wider as the growth of the inmate and the inclemency of
the season demand. Even in winter, if the weather is mild, and the sun
smiles upon the threshold of his dwelling, one may sometimes surprise
the Cricket thrusting out small quantities of loosened earth, a sign of
enlargement and of further burrowing. In the midst of the joys of spring
the cares of the house still continue; it is constantly restored and
perfected until the death of the occupant.
April comes to an end, and the song of the Cricket commences. At first
we hear only timid and occasional solos; but very soon there is a
general symphony, when every scrap of turf has its performer. I am
inclined to place the Cricket at the head of the choristers of spring.
In the waste lands of Provence, when the thyme and the lavender are in
flower, the Cricket mingles his note with that of the crested lark,
which ascends like a lyrical firework, its throat swelling with music,
to its invisible station in the clouds, whence it pours its liquid arias
upon the plain below. From the ground the chorus of the Crickets
replies. It is monotonous and artless, yet how well it harmonises, in
its very simplicity, with the rustic gaiety of a world renewed! It is
the hosanna of the awakening, the alleluia of the germinating seed and
the sprouting blade. To which of the two performers should the palm be
given? I should award it to the Cricket; he triumphs by force of numbers
and his never-ceasing note. The lark hushes her song, that the blue-grey
fields of lavender, swinging their aromatic censers before the sun, may
hear the Cricket alone at his humble, solemn celebration.
But here the anatomist intervenes, roughly demanding of the Cricket:
"Show me your instrument, the source of your music!" Like all things of
real value, it is very simple; it is based on the same principle as that
of the locusts; there is the toothed fiddlestick and the vibrating
tympanum.
The right wing-cover overlaps the left and almost completely covers it,
except for the sudden fold which encases the insect's flank. This
arrangement is the reverse of that exhibited by the green grasshopper,
the Decticus, the Ephippigera, and their relations. The Cricket is
right-handed, the others left-handed. The two wing-covers have the same
structure. To know one is to know the other. Let us examine that on the
right hand.
It is almost flat on the back, but suddenly folds over at the side, the
turn being almost at right angles. This lateral fold encloses the flank
of the abdomen and is covered with fine oblique and parallel nervures.
The powerful nervures of the dorsal portion of the wing-cover are of the
deepest black, and their general effect is that of a complicated design,
not unlike a tangle of Arabic caligraphy.
Seen by transmitted light the wing-cover is of a very pale reddish
colour, excepting two large adjacent spaces, one of which, the larger
and anterior, is triangular in shape, while the other, the smaller and
posterior, is oval. Each space is surrounded by a strong nervure and
goffered by slight wrinkles or depressions. These two spaces represent
the mirror of the locust tribe; they constitute the sonorous area. The
substance of the wing-cover is finer here than elsewhere, and shows
traces of iridescent though somewhat smoky colour.
These are parts of an admirable instrument, greatly superior to that of
the Decticus. The five hundred prisms of the bow biting upon the ridges
of the wing-cover opposed to it set all four tympanums vibrating at
once; the lower pair by direct friction, the upper pair by the vibration
of the wing-cover itself. What a powerful sound results! The Decticus,
endowed with only one indifferent "mirror," can be heard only at a few
paces; the Cricket, the possessor of four vibratory areas, can be heard
at a hundred yards.
The Cricket rivals the Cigale in loudness, but his note has not the
displeasing, raucous quality of the latter. Better still: he has the
gift of expression, for he can sing loud or soft. The wing-covers, as we
have seen, are prolonged in a deep fold over each flank. These folds are
the dampers, which, as they are pressed downwards or slightly raised,
modify the intensity of the sound, and according to the extent of their
contact with the soft abdomen now muffle the song to a _mezza voce_ and
now let it sound _fortissimo_.
Peace reigns in the cage until the warlike instinct of the mating period
breaks out. These duels between rivals are frequent and lively, but not
very serious. The two rivals rise up against one another, biting at one
another's heads--these solid, fang-proof helmets--roll each other over,
pick themselves up, and separate. The vanquished Cricket scuttles off as
fast as he can; the victor insults him by a couple of triumphant and
boastful chirps; then, moderating his tone, he tacks and veers about the
desired one.
The lover proceeds to make himself smart. Hooking one of his antennæ
towards him with one of his free claws, he takes it between his
mandibles in order to curl it and moisten it with saliva. With his long
hind legs, spurred and laced with red, he stamps with impatience and
kicks out at nothing. Emotion renders him silent. His wing-covers are
nevertheless in rapid motion, but are no longer sounding, or at most
emit but an unrhythmical rubbing sound.
Presumptuous declaration! The female Cricket does not run to hide
herself in the folds of her lettuce leaves; but she lifts the curtain a
little, and looks out, and wishes to be seen:--
_Et fugit ad salices, et se cupit ante videri._
She flies towards the brake, but hopes first to be perceived, said the
poet of the delightful eclogue, two thousand years ago. Sacred
provocations of lovers, are they not in all ages the same?
CHAPTER XI
THE ITALIAN CRICKET
My house shelters no specimens of the domestic Cricket, the guest of
bakeries and rustic hearths. But although in my village the chinks under
the hearthstones are mute, the nights of summer are musical with a
singer little known in the North. The sunny hours of spring have their
singer, the Field-Cricket of which I have written; while in the summer,
during the stillness of the night, we hear the note of the Italian
Cricket, the _OEcanthus pellucens_, Scop. One diurnal and one
nocturnal, between them they share the kindly half of the year. When the
Field-Cricket ceases to sing it is not long before the other begins its
serenade.
The Italian Cricket has not the black costume and heavy shape
characteristic of the family. It is, on the contrary, a slender, weakly
creature; its colour very pale, indeed almost white, as is natural in
view of its nocturnal habits. In handling it one is afraid of crushing
it between the fingers. It lives an aerial existence; on shrubs and
bushes of all kinds, on tall herbage and grasses, and rarely descends to
the earth. Its song, the pleasant voice of the calm, hot evenings from
July to October, commences at sunset and continues for the greater part
of the night.
This song is familiar to all Provençals; for the least patch of thicket
or tuft of grasses has its group of instrumentalists. It resounds even
in the granaries, into which the insect strays, attracted thither by the
fodder. But no one, so mysterious are the manners of the pallid Cricket,
knows exactly what is the source of the serenade, which is often, though
quite erroneously, attributed to the common field-cricket, which at this
period is silent and as yet quite young.
The song consists of a _Gri-i-i, Gri-i-i_, a slow, gentle note, rendered
more expressive by a slight tremor. Hearing it, one divines the extreme
tenuity and the amplitude of the vibrating membranes. If the insect is
not in any way disturbed as it sits in the low foliage, the note does
not vary, but at the least noise the performer becomes a ventriloquist.
First of all you hear it there, close by, in front of you, and the next
moment you hear it over there, twenty yards away; the double note
decreased in volume by the distance.
You go forward. Nothing is there. The sound proceeds again from its
original point. But no--it is not there; it is to the left now--unless
it is to the right--or behind.... Complete confusion! It is impossible
to detect, by means of the ear, the direction from which the chirp
really comes. Much patience and many precautions will be required before
you can capture the insect by the light of the lantern. A few specimens
caught under these conditions and placed in a cage have taught me the
little I know concerning the musician who so perfectly deceives our
ears.
The wing-covers are both formed of a dry, broad membrane, diaphanous and
as fine as the white skin on the outside of an onion, which is capable
of vibrating over its whole area. Their shape is that of the segment of
a circle, cut away at the upper end. This segment is bent at a right
angle along a strong longitudinal nervure, and descends on the outer
side in a flap which encloses the insect's flank when in the attitude of
repose.
The right wing-cover overlaps the left. Its inner edge carries, on the
under side, near the base, a callosity from which five radiating
nervures proceed; two of them upwards and two downwards, while the fifth
runs approximately at right angles to these. This last nervure, which is
of a slightly reddish hue, is the fundamental element of the musical
device; it is, in short, the bow, the fiddlestick, as is proved by the
fine notches which run across it. The rest of the wing-cover shows a few
more nervures of less importance, which hold the membrane stretched
tight, but do not form part of the friction apparatus.
The left or lower wing-cover is of similar structure, with the
difference that the bow, the callosity, and the nervures occupy the
upper face. It will be found that the two bows--that is, the toothed or
indented nervures--cross one another obliquely.
When the note has its full volume, the wing-covers are well raised above
the body like a wide gauzy sail, only touching along the internal edges.
The two bows, the toothed nervures, engage obliquely one with the other,
and their mutual friction causes the sonorous vibration of the two
stretched membranes.
[Illustration: THE ITALIAN CRICKET.]
The sound can be modified accordingly as the strokes of each bow bear
upon the callosity, which is itself serrated or wrinkled, or on one of
the four smooth radiating nervures. Thus in part are explained the
illusions produced by a sound which seems to come first from one point,
then from another, when the timid insect is alarmed.
The production of loud or soft resounding or muffled notes, which gives
the illusion of distance, the principal element in the art of the
ventriloquist, has another and easily discovered source. To produce the
loud, open sounds the wing-covers are fully lifted; to produce the
muted, muffled notes they are lowered. When lowered their outer edges
press more or less lightly on the soft flanks of the insect, thus
diminishing the vibratory area and damping the sound.
The gentle touch of a finger-tip muffles the sharp, loud ringing of a
glass tumbler or "musical-glass" and changes it into a veiled,
indefinite sound which seems to come from a distance. The White Cricket
knows this secret of acoustics. It misleads those that seek it by
pressing the edge of its vibrating membranes to the soft flesh of its
abdomen. Our musical instruments have their dampers; that of the
_OEcanthus pellucens_ rivals and surpasses them in simplicity of means
and perfection of results.
The Field-Cricket and its relatives also vary the volume of their song
by raising or lowering the elytra so as to enclose the abdomen in a
varying degree, but none of them can obtain by this method results so
deceptive as those produced by the Italian Cricket.
To this illusion of distance, which is a source of perpetually renewed
surprise, evoked by the slightest sound of our footsteps, we must add
the purity of the sound, and its soft tremolo. I know of no insect voice
more gracious, more limpid, in the profound peace of the nights of
August. How many times, _per amica silentia lunæ_, have I lain upon the
ground, in the shelter of a clump of rosemary, to listen to the
delicious concert!
The nocturnal Cricket sings continually in the gardens. Each tuft of the
red-flowered cistus has its band of musicians, and each bush of fragrant
lavender. The shrubs and the terebinth-trees contain their orchestras.
With its clear, sweet voice, all this tiny world is questioning,
replying, from bush to bush, from tree to tree; or rather, indifferent
to the songs of others, each little being is singing his joys to himself
alone.
Above my head the constellation of Cygnus stretches its great cross
along the Milky Way; below, all around me, palpitates the insect
symphony. The atom telling of its joys makes me forget the spectacle of
the stars. We know nothing of these celestial eyes which gaze upon us,
cold and calm, with scintillations like the blinking of eyelids.
Science tells us of their distance, their speeds, their masses, their
volumes; it burdens us with stupendous numbers and stupefies us with
immensities; but it does not succeed in moving us. And why? Because it
lacks the great secret: the secret of life. What is there, up there?
What do these suns warm? Worlds analogous to ours, says reason; planets
on which life is evolving in an endless variety of forms. A superb
conception of the universe, but after all a pure conception, not based
upon patent facts and infallible testimony at the disposal of one and
all. The probable, even the extremely probable, is not the obvious, the
evident, which forces itself irresistibly and leaves no room for doubt.
But in your company, O my Crickets, I feel the thrill of life, the soul
of our native lump of earth; and for this reason, as I lean against the
hedge of rosemary, I bestow only an absent glance upon the constellation
of Cygnus, but give all my attention to your serenade. A little animated
slime, capable of pleasure and pain, surpasses in interest the universe
of dead matter.
CHAPTER XII
THE SISYPHUS BEETLE.--THE INSTINCT OF PATERNITY
The duties of paternity are seldom imposed on any but the higher
animals. They are most notable in the bird; and the furry peoples acquit
themselves honourably. Lower in the scale we find in the father a
general indifference as to the fate of the family. Very few insects form
exceptions to this rule. Although all are imbued with a mating instinct
that is almost frenzied, nearly all, when the passion of the moment is
appeased, terminate then and there their domestic relations, and
withdraw, indifferent to the brood, which has to look after itself as
best it may.
This paternal coldness, which would be odious in the higher walks of
animal life, where the weakness of the young demands prolonged
assistance, has in the insect world the excuse that the new-born young
are comparatively robust, and are able, without help, to fill their
mouths and stomachs, provided they find themselves in propitious
surroundings. All that the prosperity of the race demands of the
Pierides, or Cabbage Butterflies, is that they should deposit their eggs
on the leaves of the cabbage; what purpose would be served by the
instincts of a father? The botanical instinct of the mother needs no
assistance. At the period of laying the father would be in the way. Let
him pursue his flirtations elsewhere; the laying of eggs is a serious
business.
In the case of the majority of insects the process of education is
unknown, or summary in the extreme. The insect has only to select a
grazing-ground upon which its family will establish itself the moment it
is hatched; or a site which will allow the young to find their proper
sustenance for themselves. There is no need of a father in these various
cases. After mating, the discarded male, who is henceforth useless,
drags out a lingering existence of a few days, and finally perishes
without having given the slightest assistance in the work of installing
his offspring.
But matters are not everywhere so primitive as this. There are tribes in
which an inheritance is prepared for the family which will assure it
both of food and of shelter in advance. The Hymenoptera in particular
are past-masters in the provision of cellars, jars, and other utensils
in which the honey-paste destined for the young is stored; they are
perfect in the art of excavating storehouses of food for their grubs.
This stupendous labour of construction and provisioning, this labour
that absorbs the insect's whole life, is the work of the mother only,
who wears herself out at her task. The father, intoxicated with
sunlight, lies idle on the threshold of the workshop, watching the
heroic female at her work, and regards himself as excused from all
labour when he has plagued his neighbours a little.
Does he never perform useful work? Why does he not follow the example
of the swallows, each of whom brings a fair share of the straw and
mortar for the building of the nest and the midges for the young brood?
No, he does nothing; perhaps alleging the excuse of his relative
weakness. But this is a poor excuse; for to cut out little circles from
a leaf, to rake a little cotton from a downy plant, or to gather a
little mortar from a muddy spot, would hardly be a task beyond his
powers. He might very well collaborate, at least as labourer; he could
at least gather together the materials for the more intelligent mother
to place in position. The true motive of his idleness is ineptitude.
It is a curious thing that the Hymenoptera, the most skilful of all
industrial insects, know nothing of paternal labour. The male of the
genus, in whom we should expect the requirements of the young to develop
the highest aptitudes, is as useless as a butterfly, whose family costs
so little to establish. The actual distribution of instinct upsets our
most reasonable previsions.
It upsets our expectations so completely that we are surprised to find
in the dung-beetle the noble prerogative which is lacking in the bee
tribe. The mates of several species of dung-beetle keep house together
and know the worth of mutual labour. Consider the male and female
Geotrupes, which prepare together the patrimony of their larvæ; in their
case the father assists his companion with the pressure of his robust
body in the manufacture of their balls of compressed nutriment. These
domestic habits are astonishing amidst the general isolation.
To this example, hitherto unique, my continual researches in this
direction permit me to-day to add three others which are fully as
interesting. All three are members of the corporation of dung-beetles. I
will relate their habits, but briefly, as in many respects their history
is the same as that of the Sacred Scarabæus, the Spanish Copris, and
others.
The first example is the Sisyphus beetle (_Sisyphus Schæfferi_, Lin.),
the smallest and most industrious of our pill-makers. It has no equal in
lively agility, grotesque somersaults, and sudden tumbles down the
impossible paths or over the impracticable obstacles to which its
obstinacy is perpetually leading it. In allusion to these frantic
gymnastics Latreille has given the insect the name of Sisyphus, after
the celebrated inmate of the classic Hades. This unhappy spirit
underwent terrible exertions in his efforts to heave to the top of a
mountain an enormous rock, which always escaped him at the moment of
attaining the summit, and rolled back to the foot of the slope. Begin
again, poor Sisyphus, begin again, begin again always! Your torments
will never cease until the rock is firmly placed upon the summit of the
mountain.
I like this myth. It is, in a way, the history of many of us; not odious
scoundrels worthy of eternal torments, but worthy and laborious folk,
useful to their neighbours. One crime alone is theirs to expiate: the
crime of poverty. Half a century or more ago, for my own part, I left
many blood-stained tatters on the crags of the inhospitable mountain; I
sweated, strained every nerve, exhausted my veins, spent without
reckoning my reserves of energy, in order to carry upward and lodge in
a place of security that crushing burden, my daily bread; and hardly was
the load balanced but it once more slipped downwards, fell, and was
engulfed. Begin again, poor Sisyphus; begin again, until your burden,
falling for the last time, shall crush your head and set you free at
length.
The Sisyphus of the naturalists knows nothing of these tribulations.
Agile and lively, careless of slope or precipice, he trundles his load,
which is sometimes food for himself, sometimes for his offspring. He is
very rare hereabouts; I should never have succeeded in obtaining a
sufficient number of specimens for my purpose but for an assistant whom
I may opportunely present to the reader, for he will be mentioned again
in these recitals.
This is my son, little Paul, aged seven. An assiduous companion of the
chase, he knows better than any one of his age the secrets of the
Cigale, the Cricket, and especially of the dung-beetle, his great
delight. At a distance of twenty yards his clear sight distinguishes the
refuse-tip of a beetle's burrow from a chance lump of earth; his fine
ear will catch the chirping of a grasshopper inaudible to me. He lends
me his sight and hearing, and I in return make him free of my thoughts,
which he welcomes attentively, raising his wide blue eyes questioningly
to mine.
What an adorable thing is the first blossoming of the intellect! Best of
all ages is that when the candid curiosity awakens and commences to
acquire knowledge of every kind. Little Paul has his own insectorium, in
which the Scarabæus makes his balls; his garden, the size of a
handkerchief, in which he grows haricot beans, which are often dug up to
see if the little roots are growing longer; his plantation, containing
four oak-trees an inch in height, to which the acorns still adhere.
These serve as diversions after the arid study of grammar, which goes
forward none the worse on that account.
What beautiful and useful knowledge the teaching of natural history
might put into childish heads, if only science would consider the very
young; if our barracks of universities would only combine the lifeless
study of books with the living study of the fields; if only the red tape
of the curriculum, so dear to bureaucrats, would not strangle all
willing initiative. Little Paul and I will study as much as possible in
the open country, among the rosemary bushes and arbutus. There we shall
gain vigour of body and of mind; we shall find the true and the
beautiful better than in school-books.
To-day the blackboard has a rest; it is a holiday. We rise early, in
view of the intended expedition; so early that we must set out fasting.
But no matter; when we are hungry we shall rest in the shade, and you
will find in my knapsack the usual viaticum--apples and a crust of
bread. The month of May is near; the Sisyphus should have appeared. Now
we must explore at the foot of the mountain, the scanty pastures through
which the herds have passed; we must break with our fingers, one by one,
the cakes of sheep-dung dried by the sun, but still retaining a spot of
moisture in the centre. There we shall find Sisyphus, cowering and
waiting until the evening for fresher pasturage.
Possessed of this secret, which I learned from previous fortuitous
discoveries, little Paul immediately becomes a master in the art of
dislodging the beetle. He shows such zeal, has such an instinct for
likely hiding-places, that after a brief search I am rich beyond my
ambitions. Behold me the owner of six couples of Sisyphus beetles: an
unheard-of number, which I had never hoped to obtain.
For their maintenance a wire-gauze cover suffices, with a bed of sand
and diet to their taste. They are very small, scarcely larger than a
cherry-stone. Their shape is extremely curious. The body is dumpy,
tapering to an acorn-shaped posterior; the legs are very long,
resembling those of the spider when outspread; the hinder legs are
disproportionately long and curved, being thus excellently adapted to
enlace and press the little pilule of dung.
Mating takes place towards the beginning of May, on the surface of the
soil, among the remains of the sheep-dung on which the beetles have been
feeding. Soon the moment for establishing the family arrives. With equal
zeal the two partners take part in the kneading, transport, and baking
of the food for their offspring. With the file-like forelegs a morsel of
convenient size is shaped from the piece of dung placed in the cage.
Father and mother manipulate the piece together, striking it blows with
their claws, compressing it, and shaping it into a ball about the size
of a big pea.
As in the case of the _Scarabæus sacer_, the exact spherical form is
produced without the mechanical device of rolling the ball. Before it is
moved, even before it is cut loose from its point of support, the
fragment is modelled into the shape of a sphere. The beetle as geometer
is aware of the form best adapted to the long preservation of preserved
foods.
The ball is soon ready. It must now be forced to acquire, by means of a
vigorous rolling, the crust which will protect the interior from a too
rapid evaporation. The mother, recognisable by her slightly robuster
body, takes the place of honour in front. Her long hinder legs on the
soil, her forelegs on the ball, she drags it towards her as she walks
backwards. The father pushes behind, moving tail first, his head held
low. This is exactly the method of the Scarabæus beetles, which also
work in couples, though for another object. The Sisyphus beetles harness
themselves to provide an inheritance for their larvæ; the larger insects
are concerned in obtaining the material for a banquet which the two
chance-met partners will consume underground.
The couple set off, with no definite goal ahead, across the
irregularities of the soil, which cannot be avoided by a leader who
hauls backwards. But even if the Sisyphus saw the obstacles she would
not try to evade them: witness her obstinate endeavour to drag her load
up the wire gauze of her cage!
A hopeless undertaking! Fixing her hinder claws in the meshes of the
wire gauze the mother drags her burden towards her; then, enlacing it
with her legs, she holds it suspended. The father, finding no purchase
for his legs, clutches the ball, grows on to it, so to speak, thus
adding his weight to that of the burden, and awaits events. The effort
is too great to last. Ball and beetle fall together. The mother, from
above, gazes a moment in surprise, and suddenly lets herself fall, only
to re-embrace the ball and recommence her impracticable efforts to scale
the wall. After many tumbles the attempt is at last abandoned.
Even on level ground the task is not without its difficulties. At every
moment the load swerves on the summit of a pebble, a fragment of gravel;
the team are overturned, and lie on their backs, kicking their legs in
the air. This is a mere nothing. They pick themselves up and resume
their positions, always quick and lively. The accidents which so often
throw them on their backs seem to cause them no concern; one would even
think they were invited. The pilule has to be matured, given a proper
consistency. In these conditions falls, shocks, blows, and jolts might
well enter into the programme. This mad trundling lasts for hours and
hours.
Finally, the mother, considering that the matter has been brought to a
satisfactory conclusion, departs in search of a favourable place for
storage. The father, crouched upon the treasure, waits. If the absence
of his companion is prolonged he amuses himself by rapidly whirling the
pill between his hind legs, which are raised in the air. He juggles with
the precious burden; he tests its perfections between his curved legs,
calliper-wise. Seeing him frisking in this joyful occupation, who can
doubt that he experiences all the satisfactions of a father assured of
the future of his family? It is I, he seems to say, it is I who have
made this loaf, so beautifully round; it is I who have made the hard
crust to preserve the soft dough; it is I who have baked it for my sons!
And he raises on high, in the sight of all, this magnificent testimonial
of his labours.
But now the mother has chosen the site. A shallow pit is made, the mere
commencement of the projected burrow. The ball is pushed and pulled
until it is close at hand. The father, a vigilant watchman, still
retains his hold, while the mother digs with claws and head. Soon the
pit is deep enough to receive the ball; she cannot dispense with the
close contact of the sacred object; she must feel it bobbing behind her,
against her back, safe from all parasites and robbers, before she can
decide to burrow further. She fears what might happen to the precious
loaf if it were abandoned at the threshold of the burrow until the
completion of the dwelling. There is no lack of midges and tiny
dung-beetles--Aphodiinæ--which might take possession of it. It is only
prudent to be distrustful.
So the ball is introduced into the pit, half in and half out of the
mouth of the burrow. The mother, below, clasps and pulls; the father,
above, moderates the jolts and prevents it from rolling. All goes well.
Digging is resumed, and the descent continues, always with the same
prudence; one beetle dragging the load, the other regulating its descent
and clearing away all rubbish that might hinder the operation. A few
more efforts, and the ball disappears underground with the two miners.
What follows will be, for a time at least, only a repetition of what we
have seen. Let us wait half a day or so.
If our vigilance is not relaxed we shall see the father regain the
surface alone, and crouch in the sand near the mouth of the burrow.
Retained by duties in the performance of which her companion can be of
no assistance, the mother habitually delays her reappearance until the
following day. When she finally emerges the father wakes up, leaves his
hiding place, and rejoins her. The reunited couple return to their
pasturage, refresh themselves, and then cut out another ball of dung.
As before, both share the work; the hewing and shaping, the transport,
and the burial in ensilage.
This conjugal fidelity is delightful; but is it really the rule? I
should not dare to affirm that it is. There must be flighty individuals
who, in the confusion under a large cake of droppings, forget the fair
confectioners for whom they have worked as journeymen, and devote
themselves to the services of others, encountered by chance; there must
be temporary unions, and divorces after the burial of a single pellet.
No matter: the little I myself have seen gives me a high opinion of the
domestic morals of the Sisyphus.
Let us consider these domestic habits a little further before coming to
the contents of the burrow. The father works fully as hard as the mother
at the extraction and modelling of the pellet which is destined to be
the inheritance of a larva; he shares in the work of transport, even if
he plays a secondary part; he watches over the pellet when the mother is
absent, seeking for a suitable site for the excavation of the cellar; he
helps in the work of digging; he carries away the rubbish from the
burrow; finally, to crown all these qualities, he is in a great measure
faithful to his spouse.
The Scarabæus exhibits some of these characteristics. He also assists
his spouse in the preparation of pellets of dung; he also assists her to
transport the pellets, the pair facing each other and the female going
backwards. But as I have stated already, the motive of this mutual
service is selfish; the two partners labour only for their own good. The
feast is for themselves alone. In the labours that concern the family
the female Scarabæus receives no assistance. Alone she moulds her
sphere, extracts it from the lump and rolls it backwards, with her back
to her task, in the position adopted by the male Sisyphus; alone she
excavates her burrow, and alone she buries the fruit of her labour.
Oblivious of the gravid mother and the future brood, the male gives her
no assistance in her exhausting task. How different to the little
pellet-maker, the Sisyphus!
It is now time to visit the burrow. At no very great depth we find a
narrow chamber, just large enough for the mother to move around at her
work. Its very exiguity proves that the male cannot remain underground;
so soon as the chamber is ready he must retire in order to leave the
female room to move. We have, in fact, seen that he returns to the
surface long before the female.
The contents of the cellar consist of a single pellet, a masterpiece of
plastic art. It is a miniature reproduction of the pear-shaped ball of
the Scarabæus, a reproduction whose very smallness gives an added value
to the polish of the surface and the beauty of its curves. Its larger
diameter varies from half to three-quarters of an inch. It is the most
elegant product of the dung-beetle's art.
But this perfection is of brief duration. Very soon the little "pear"
becomes covered with gnarled excrescences, black and twisted, which
disfigure it like so many warts. Part of the surface, which is otherwise
intact, disappears under a shapeless mass. The origin of these knotted
excrescences completely deceived me at first. I suspected some
cryptogamic vegetation, some _Spheriæcæa_, for example, recognisable by
its black, knotted, incrusted growth. It was the larva that showed me my
mistake.
The larva is a maggot curved like a hook, carrying on its back an ample
pouch or hunch, forming part of its alimentary canal. The reserve of
excreta in this hunch enables it to seal accidental perforations of the
shell of its lodging with an instantaneous jet of mortar. These sudden
emissions, like little worm-casts, are also practised by the Scarabæus,
but the latter rarely makes use of them.
The larvæ of the various dung-beetles utilise their alimentary residues
in rough-casting their houses, which by their dimensions lend themselves
to this method of disposal, while evading the necessity of opening
temporary windows by which the ordure can be expelled. Whether for lack
of sufficient room, or for other reasons which escape me, the larva of
the Sisyphus, having employed a certain amount in the smoothing of the
interior, ejects the rest of its digestive products from its dwelling.
Let us examine one of these "pears" when the inmate is already partly
grown. Sooner or later we shall see a spot of moisture appear at some
point on the surface; the wall softens, becomes thinner, and then,
through the softened shell, a jet of dark green excreta rises and falls
back upon itself in corkscrew convolutions. One excrescence the more has
been formed; as it dries it becomes black.
What has occurred? The larva has opened a temporary breach in the wall
of its shell; and through this orifice, in which a slight thickness of
the outer glaze still remains, it has expelled the excess of mortar
which it could not employ within. This practice of forming oubliettes in
the shell of its prison does not endanger the grub, as they are
immediately closed, and hermetically sealed by the base of the jet,
which is compressed as by a stroke of a trowel. The stopper is so
quickly put in place that the contents remain moist in spite of the
frequent breaches made in the shell of the "pear." There is no danger of
an influx of the dry outer air.
The Sisyphus seems to be aware of the peril which later on, in the
dog-days, will threaten its "pear," small as it is, and so near the
surface of the ground. It is extremely precocious. It labours in April
and May when the air is mild. In the first fortnight of July, before the
terrible dog-days have arrived, the members of its family break their
shells and set forth in search of the heap of droppings which will
furnish them with food and lodging during the fierce days of summer.
Then come the short but pleasant days of autumn, the retreat underground
and the winter torpor, the awakening of spring, and finally the cycle is
closed by the festival of pellet-making.
One word more as to the fertility of the Sisyphus. My six couples under
the wire-gauze cover furnished me with fifty-seven inhabited pellets.
This gives an average of more than nine to each couple; a figure which
the _Scarabæus sacer_ is far from attaining. To what should we attribute
this superior fertility? I can only see one cause: the fact that the
male works as valiantly as the female. Family cares too great for the
strength of one are not too heavy when there are two to support them.
CHAPTER XIII
A BEE-HUNTER: THE _PHILANTHUS AVIPORUS_
To encounter among the Hymenoptera, those ardent lovers of flowers, a
species which goes a-hunting on its own account is, to say the least of
it, astonishing. That the larder of the larvæ should be provisioned with
captured prey is natural enough; but that the provider, whose diet is
honey, should itself devour its captives is a fact both unexpected and
difficult to comprehend. We are surprised that a drinker of nectar
should become a drinker of blood. But our surprise abates if we consider
the matter closely. The double diet is more apparent than real; the
stomach which fills itself with the nectar of flowers does not gorge
itself with flesh. When she perforates the rump of her victim the
Odynerus does not touch the flesh, which is a diet absolutely contrary
to her tastes; she confines herself to drinking the defensive liquid
which the grub distils at the end of its intestine. For her this liquid
is doubtless a beverage of delicious flavour, with which she relieves
from time to time her staple diet of the honey distilled by flowers,
some highly spiced condiment, appetiser or aperient, or perhaps--who
knows?--a substitute for honey. Although the qualities of the liquid
escape me, I see at least that Odynerus cares nothing for the rest.
Once the pouch is emptied the larva is abandoned as useless offal, a
certain sign of non-carnivorous appetites. Under these conditions the
persecutor of Chrysomela can no longer be regarded as guilty of an
unnatural double dietary.
We may even wonder whether other species also are not apt to draw some
direct profit from the hunting imposed upon them by the needs of the
family. The procedure of Odynerus in opening the anal pouch is so far
removed from the usual that we should not anticipate many imitators; it
is a secondary detail, and impracticable with game of a different kind.
But there may well be a certain amount of variety in the means of direct
utilisation. Why, for example, when the victim which has just been
paralysed or rendered insensible by stinging contains in the stomach a
delicious meal, semi-liquid or liquid in consistency, should the hunter
scruple to rob the half-living body and force it to disgorge without
injuring the quality of its flesh? There may well be robbers of the
moribund, attracted not by their flesh but by the appetising contents of
their stomachs.
As a matter of fact there are such, and they are numerous. In the first
rank we may cite that hunter of the domestic bee, _Philanthus aviporus_
(Latreille). For a long time I suspected Philanthus of committing such
acts of brigandage for her own benefit, having many times surprised her
gluttonously licking the honey-smeared mouth of the bee; I suspected
that her hunting of the bee was not undertaken entirely for the benefit
of her larvæ. The suspicion was worth experimental confirmation. At the
time I was interested in another question also: I wanted to study,
absolutely at leisure, the methods by which the various predatory
species dealt with their victims. In the case of Philanthus I made use
of the improvised cage already described; and Philanthus it was who
furnished me with my first data on the subject. She responded to my
hopes with such energy that I thought myself in possession of an
unequalled method of observation, by means of which I could witness
again and again, to satiety even, incidents of a kind so difficult to
surprise in a state of nature. Alas! the early days of my acquaintance
with Philanthus promised me more than the future had in store for me!
Not to anticipate, however, let us place under the bell-glass the hunter
and the game. I recommend the experiment to whomsoever would witness the
perfection with which the predatory Hymenoptera use their stings. The
result is not in doubt and the waiting is short; the moment the prey is
perceived in an attitude favourable to her designs, the bandit rushes at
it, and all is over. In detail, the tragedy develops as follows:
I place under a bell-glass a Philanthus and two or three domestic bees.
The prisoners climb the glass walls, on the more strongly lighted side;
they ascend, descend, and seek to escape; the polished, vertical surface
is for them quite easy to walk upon. They presently quiet down, and the
brigand begins to notice her surroundings. The antennæ point forward,
seeking information; the hinder legs are drawn up with a slight
trembling, as of greed and rapacity, in the thighs; the head turns to
the right and the left, and follows the evolutions of the bees against
the glass. The posture of the scoundrelly insect is strikingly
expressive; one reads in it the brutal desires of a creature in ambush,
the cunning patience that postpones attack. The choice is made, and
Philanthus throws herself upon her victim.
Turn by turn tumbled and tumbling, the two insects roll over and over.
But the struggle soon quiets down, and the assassin commences to plunder
her prize. I have seen her adopt two methods. In the first, more usual
than the other, the bee is lying on the ground, upon its back, and
Philanthus, mouth to mouth and abdomen to abdomen, clasps it with her
six legs, while she seizes its neck in her mandibles. The abdomen is
then curved forward and gropes for a moment for the desired spot in the
upper part of the thorax, which it finally reaches. The sting plunges
into the victim, remains in the wound for a moment, and all is over.
Without loosing the victim, which is still tightly clasped, the murderer
restores her abdomen to the normal position and holds it pressed against
that of the bee.
By the second method Philanthus operates standing upright. Resting on
the hinder feet and the extremity of the folded wings, she rises proudly
to a vertical position, holding the bee facing her by her four anterior
claws. In order to get the bee into the proper position for the final
stroke, she swings the poor creature round and back again with the
careless roughness of a child dandling a doll. Her pose is magnificent,
solidly based upon her sustaining tripod, the two posterior thighs and
the end of the wings, she flexes the abdomen forwards and upwards, and,
as before, stings the bee in the upper part of the thorax. The
originality of her pose at the moment of striking surpasses anything I
have ever witnessed.
The love of knowledge in matters of natural history is not without its
cruelties. To make absolutely certain of the point attained by the
sting, and to inform myself completely concerning this horrible talent
for murder, I have provoked I dare not confess how many assassinations
in captivity. Without a single exception, the bee has always been stung
in the throat. In the preparations for the final blow the extremity of
the abdomen may of course touch here and there, at different points of
the thorax or abdomen, but it never remains there, nor is the sting
unsheathed, as may easily be seen. Once the struggle has commenced the
Philanthus is so absorbed in her operations that I can remove the glass
cover and follow every detail of the drama with my magnifying-glass.
The invariable situation of the wound being proved, I bend back the head
of the bee, so as to open the articulation. I see under what we may call
the chin of the bee a white spot, hardly a twenty-fifth of an inch
square, where the horny integuments are lacking, and the fine skin is
exposed uncovered. It is there, always there, in that tiny defect in the
bee's armour, that the sting is inserted. Why is this point attacked
rather than another? Is it the only point that is vulnerable? Stretch
open the articulation of the corselet to the rear of the first pair of
legs. There you will see an area of defenceless skin, fully as delicate
as that of the throat, but much more extensive. The horny armour of the
bee has no larger breach. If the Philanthus were guided solely by
considerations of vulnerability she would certainly strike there,
instead of insistently seeking the narrow breach in the throat. The
sting would not grope or hesitate, it would find its mark at the first
attempt. No; the poisoned thrust is not conditioned by mechanical
considerations; the murderer disdains the wide breach in the corselet
and prefers the lesser one beneath the chin, for purely logical reasons
which we will now attempt to elicit.
The moment the bee is stung I release it from the aggressor. I am struck
in the first place by the sudden inertia of the antennæ and the various
members of the mouth; organs which continue to move for so long a time
in the victims of most predatory creatures. I see none of the
indications with which my previous studies of paralysed victims have
made me familiar: the antennæ slowly waving, the mandibles opening and
closing, the palpæ trembling for days, for weeks, even for months. The
thighs tremble for a minute or two at most; and the struggle is over.
Henceforth there is complete immobility. The significance of this sudden
inertia is forced upon me: the Philanthus has stabbed the cervical
ganglions. Hence the sudden immobility of all the organs of the head:
hence the real, not the apparent death of the bee. The Philanthus does
not paralyse merely, but kills.
This is one step gained. The murderer chooses the point below the chin
as the point of attack, in order to reach the principal centres of
innervation, the cephalic ganglions, and thus to abolish life at a
single blow. The vital centres being poisoned, immediate death must
follow. If the object of the Philanthus were merely to cause paralysis
she would plunge her sting into the defective corselet, as does the
Cerceris in attacking the weevil, whose armour is quite unlike the
bee's. Her aim is to kill outright, as we shall presently see; she wants
a corpse, not a paralytic. We must admit that her technique is
admirable; our human murderers could do no better.
Her posture of attack, which is very different to that of the
paralysers, is infallibly fatal to the victim. Whether she delivers the
attack in the erect position or prone, she holds the bee before her,
head to head and thorax to thorax. In this position it suffices to flex
the abdomen in order to reach the joint of the neck, and to plunge the
sting obliquely upwards into the head of the captive. If the bee were
seized in the inverse position, or if the sting were to go slightly
astray, the results would be totally different; the sting, penetrating
the bee in a downward direction, would poison the first thoracic
ganglion and provoke a partial paralysis only. What art, to destroy a
miserable bee! In what fencing-school did the slayer learn that terrible
upward thrust beneath the chin? And as she has learned it, how is it
that her victim, so learned in matters of architecture, so conversant
with the politics of Socialism, has so far learned nothing in her own
defence? As vigorous as the aggressor, she also carries a rapier, which
is even more formidable and more painful in its results--at all events,
when my finger is the victim! For centuries and centuries Philanthus has
stored her cellars with the corpses of bees, yet the innocent victim
submits, and the annual decimation of her race has not taught her how to
deliver herself from the scourge by a well-directed thrust. I am afraid
I shall never succeed in understanding how it is that the assailant has
acquired her genius for sudden murder while the assailed, better armed
and no less powerful, uses her dagger at random, and so far without
effect. If the one has learned something from the prolonged exercise of
the attack, then the other should also have learned something from the
prolonged exercise of defence, for attack and defence are of equal
significance in the struggle for life. Among the theorists of our day,
is there any so far-sighted as to be able to solve this enigma?
I will take this opportunity of presenting a second point which
embarrasses me; it is the carelessness--it is worse than that--the
imbecility of the bee in the presence of the Philanthus. One would
naturally suppose that the persecuted insect, gradually instructed by
family misfortune, would exhibit anxiety at the approach of the
ravisher, and would at least try to escape. But in my bell-glasses or
wire-gauze cages I see nothing of the kind. Once the first excitement
due to imprisonment has passed the bee takes next to no notice of its
terrible neighbour. I have seen it side by side with Philanthus on the
same flower; assassin and future victim were drinking from the same
goblet. I have seen it stupidly coming to inquire what the stranger
might be, as the latter crouched watching on the floor. When the
murderer springs it is usually upon some bee which passes before her,
and throws itself, so to speak, into her clutches; either thoughtlessly
or out of curiosity. There is no frantic terror, no sign of anxiety, no
tendency to escape. How is it that the experience of centuries, which is
said to teach so much to the lower creatures, has not taught the bee
even the beginning of apine wisdom: a deep-rooted horror of the
Philanthus? Does the bee count upon its sting? But the unhappy creature
is no fencer; it thrusts without method, at random. Nevertheless, let us
watch it at the final and fatal moment.
When the ravisher brings her sting into play the bee also uses its
sting, and with fury. I see the point thrusting now in this direction,
now in that; but in empty air, or grazing and slipping over the
convexity of the murderer's back, which is violently flexed. These blows
have no serious results. In the position assumed by the two as they
struggle the abdomen of the Philanthus is inside and that of the bee
outside; thus the sting of the latter has under its point only the
dorsal face of the enemy, which is convex and slippery, and almost
invulnerable, so well is it armoured. There is no breach there by which
the sting might possibly enter; and the operation takes place with the
certainty of a skilful surgeon using the lancet, despite the indignant
protests of the patient.
The fatal stroke once delivered, the murderer remains for some time on
the body of the victim, clasping it face to face, for reasons that we
must now consider. It may be that the position is perilous for
Philanthus. The posture of attack and self-protection is abandoned, and
the ventral area, more vulnerable than the back, is exposed to the sting
of the bee. Now the dead bee retains for some minutes the reflex use of
the sting, as I know to my cost: for removing the bee too soon from the
aggressor, and handling it carelessly, I have received a most effectual
sting. In her long embrace of the poisoned bee, how does Philanthus
avoid this sting, which does not willingly give up its life without
vengeance? Are there not sometimes unexpected accidents? Perhaps.
Here is a fact which encourages me in this belief. I had placed under
the bell-glass at the same time four bees and as many Eristales, in
order to judge of the entomological knowledge of Philanthus as
exemplified in the distinction of species. Reciprocal quarrels broke out
among the heterogeneous group. Suddenly, in the midst of the tumult,
the killer is killed. Who has struck the blow? Certainly not the
turbulent but pacific Eristales; it was one of the bees, which by chance
had thrust truly in the mellay. When and how? I do not know. This
accident is unique in my experience; but it throws a light upon the
question. The bee is capable of withstanding its adversary; it can, with
a thrust of its envenomed needle, kill the would-be killer. That it does
not defend itself more skilfully when it falls into the hands of its
enemy is due to ignorance of fencing, not to the weakness of the arm.
And here again arises, more insistently than before, the question I
asked but now: how is it that the Philanthus has learned for purposes of
attack what the bee has not learned for purposes of defence. To this
difficulty I see only one reply: the one knows without having learned
and the other does not know, being incapable of learning.
Let us now examine the motives which induce the Philanthus to kill its
bee instead of paralysing it. The murder once committed, it does not
release its victim for a moment, but holding it tightly clasped with its
six legs pressed against its body, it commences to ravage the corpse. I
see it with the utmost brutality rooting with its mandibles in the
articulation of the neck, and often also in the more ample articulation
of the corselet, behind the first pair of legs; perfectly aware of the
fine membrane in that part, although it does not take advantage of the
fact when employing its sting, although this vulnerable point is the
more accessible of the two breaches in the bee's armour. I see it
squeezing the bee's stomach, compressing it with its own abdomen,
crushing it as in a vice. The brutality of this manipulation is
striking; it shows that there is no more need of care and skill. The
bee is a corpse, and a little extra pushing and squeezing will not
deteriorate its quality as food, provided there is no effusion of blood;
and however rough the treatment, I have never been able to discover the
slightest wound.
These various manipulations, above all the compression of the throat,
lead to the desired result: the honey in the stomach of the bee ascends
to the mouth. I see the drops of honey welling out, lapped up by the
glutton as soon as they appear. The bandit greedily takes in its mouth
the extended and sugared tongue of the dead insect; then once more it
presses the neck and the thorax, and once more applies the pressure of
its abdomen to the honey-sac of the bee. The honey oozes forth and is
instantly licked up. This odious meal at the expense of the corpse is
taken in a truly sybaritic attitude: the Philanthus lies upon its side
with the bee between its legs. This atrocious meal lasts often half an
hour and longer. Finally the exhausted corpse is abandoned; regretfully,
it seems, for from time to time I have seen the ogre return to the feast
and repeat its manipulation of the body. After taking a turn round the
top of the bell-glass the robber of the dead returns to the victim,
squeezes it once more, and licks its mouth until the last trace of honey
has disappeared.
The frantic passion of the Philanthus for the honey of the bee is
betrayed in another fashion. When the first victim has been exhausted I
have introduced a second bee, which has been promptly stabbed under the
chin and squeezed as before in order to extract its honey. A third has
suffered the same fate without appeasing the bandit. I have offered a
fourth, a fifth; all are accepted. My notes record that a Philanthus
sacrificed six bees in succession before my eyes, and emptied them all
of honey in the approved manner. The killing came to an end not because
the glutton was satiated, but because my functions as provider were
becoming troublesome; the dry month of August leaves but few insects in
the flowerless garden. Six bees emptied of their honey--what a
gluttonous meal! Yet the famishing creature would doubtless have
welcomed a copious addition thereto had I had the means of furnishing
it!
We need not regret the failure of bees upon this occasion; for what I
have already written is sufficient testimony of the singular habits of
this murderer of bees. I am far from denying that the Philanthus has
honest methods of earning its living; I see it among the flowers, no
less assiduous than the rest of the Hymenoptera, peacefully drinking
from their cups of nectar. The male, indeed, being stingless, knows no
other means of supporting himself. The mothers, without neglecting the
flowers as a general thing, live by brigandage as well. It is said of
the Labba, that pirate of the seas, that it pounces upon sea-birds as
they rise from the waves with captured fish in their beaks. With a blow
of the beak delivered in the hollow of the stomach, the aggressor forces
the victim to drop its prey, and promptly catches it as it falls. The
victim at least escapes with nothing worse than a blow at the base of
the neck. The Philanthus, less scrupulous, falls upon the bee, stabs it
to death and makes it disgorge in order to nourish herself upon its
honey.
Nourish, I say, and I do not withdraw the expression. To support my
statement I have better reasons than those already presented. In the
cages in which various predatory Hymenoptera whose warlike habits I am
studying are confined, waiting until I have procured the desired
prey--not always an easy proceeding--I have planted a few heads of
flowers and a couple of thistle-heads sprinkled with drops of honey,
renewed at need. On these my captives feed. In the case of the
Philanthus the honeyed flowers, although welcomed, are not
indispensable. It is enough if from time to time I place in the cage a
few living bees. Half a dozen a day is about the proper allowance. With
no other diet than the honey extracted from their victims I keep my
specimens of Philanthus for a fortnight and three weeks.
So much is plain: in a state of freedom, when occasion offers, the
Philanthus must kill on her own account as she does in captivity. The
Odynerus asks nothing of the Chrysomela but a simple condiment, the
aromatic juice of the anal pouch; the Philanthus demands a full diet, or
at least a notable supplement thereto, in the form of the contents of
the stomach. What a hecatomb of bees must not a colony of these pirates
sacrifice for their personal consumption, to say nothing of their stores
of provisions! I recommend the Philanthus to the vengeance of apiarists.
For the moment we will not look further into the original causes of the
crime. Let us consider matters as we know them, with all their real or
apparent atrocity. In order to nourish herself the Philanthus levies
tribute upon the crop of the bee. This being granted, let us consider
the method of the aggressor more closely. She does not paralyse its
captives according to the customary rites of the predatory insects; she
kills them. Why? To the eyes of understanding the necessity of a sudden
death is as clear as day. Without eviscerating the bee, which would
result in the deterioration of its flesh considered as food for the
larvæ; without having recourse to the bloody extirpation of the stomach,
the Philanthus intends to obtain its honey. By skilful manipulation, by
cunning massage, she must somehow make the bee disgorge. Suppose the bee
stung in the rear of the corselet and paralysed. It is deprived of
locomotion, but not of vitality. The digestive apparatus, in particular,
retains in full, or at least in part, its normal energies, as is proved
by the frequent dejections of paralysed victims so long as the intestine
is not emptied; a fact notably exemplified by the victims of the Sphex
family; helpless creatures which I have before now kept alive for forty
days with the aid of a little sugared water. Well! without therapeutic
means, without emetics or stomach-pumps, how is a stomach intact and in
good order to be persuaded to yield up its contents? That of the bee,
jealous of its treasure, will lend itself to such treatment less readily
than another. Paralysed, the creature is inert; but there are always
internal energies and organic resistances which will not yield to the
pressure of the manipulator. In vain would the Philanthus gnaw at the
throat and squeeze the flanks; the honey would not return to the mouth
as long as a trace of life kept the stomach closed.
Matters are different with a corpse. The springs relax; the muscles
yield; the resistance of the stomach ceases, and the vessels containing
the honey are emptied by the pressure of the thief. We see, therefore,
that the Philanthus is obliged to inflict a sudden death which
instantly destroys the contractile power of the organs. Where shall the
deadly blow be delivered? The slayer knows better than we, when she
pierces the victim beneath the chin. Through the narrow breach in the
throat the cerebral ganglions are reached and immediate death ensues.
The examination of these acts of brigandage is not sufficient in view of
my incorrigible habit of following every reply by another query, until
the granite wall of the unknowable rises before me. Although the
Philanthus is skilled in forcing the bee to disgorge, in emptying the
crop distended with honey, this diabolical skill cannot be merely an
alimentary resource, above all when in common with other insects she has
access to the refectory of the flowers. I cannot regard her talents as
inspired solely by the desire of a meal obtained by the labour of
emptying the stomach of another insect. Something must surely escape us
here: the real reason for emptying the stomach. Perhaps a respectable
reason is concealed by the horrors I have recorded. What is it?
Every one will understand the vagueness which fills the observer's mind
in respect of such a question as this. The reader has the right to be
doubtful. I will spare him my suspicions, my gropings for the truth, and
the checks encountered in the search, and give him the results of my
long inquiry. Everything has its appropriate and harmonious reason. I am
too fully persuaded of this to believe that the Philanthus commits her
profanation of corpses merely to satisfy her appetite. What does the
empty stomach mean? May it not--Yes!--But, after all, who knows? Well,
let us follow up the scent.
The first care of the mothers is the welfare of the family. So far all
we know of the Philanthus concerns her talent for murder. Let us
consider her as a mother. We have seen her hunt on her own account; let
us now watch her hunt for her offspring, for the race. Nothing is
simpler than to distinguish between the two kinds of hunting. When the
insect wants a few good mouthfuls of honey and nothing else, she
abandons the bee contemptuously when she has emptied its stomach. It is
so much valueless waste, which will shrivel where it lies and be
dissected by ants. If, on the other hand, she intends to place it in the
larder as a provision for her larvæ, she clasps it with her two
intermediate legs, and, walking on the other four, drags it to and fro
along the edge of the bell-glass in search of an exit so that she may
fly off with her prey. Having recognised the circular wall as
impassable, she climbs its sides, now holding the bee in her mandibles
by the antennæ, clinging as she climbs to the vertical polished surface
with all six feet. She gains the summit of the glass, stays for a little
while in the flask-like cavity of the terminal button or handle, returns
to the ground, and resumes her circuit of the glass and her climbing,
relinquishing the bee only after an obstinate attempt to escape with it.
The persistence with which the Philanthus retains her clasp upon the
encumbering burden shows plainly that the game would go straight to the
larder were the insect at liberty.
Those bees intended for the larvæ are stung under the chin like the
others; they are true corpses; they are manipulated, squeezed, exhausted
of their honey, just as the others. There is no difference in the method
of capture nor in their after-treatment.
As captivity might possibly result in a few anomalies of action, I
decided to inquire how matters went forward in the open. In the
neighbourhood of some colonies of Philanthidæ I lay in wait, watching
for perhaps a longer time than the question justified, as it was already
settled by what occurred in captivity. My scrupulous watching at various
times was rewarded. The majority of the hunters immediately entered
their nests, carrying the bees pressed against their bodies; some halted
on the neighbouring undergrowth; and these I saw treating the bee in the
usual manner, and lapping the honey from its mouth. After these
preparations the corpse was placed in the larder. All doubt was thus
destroyed: the bees provided for the larvæ are previously carefully
emptied of their honey.
Since we are dealing with the subject, let us take the opportunity of
inquiring into the customs of the Philanthus in a state of freedom.
Making use of her victims when absolutely lifeless, so that they would
putrefy in the course of a few days, this hunter of bees cannot adopt
the customs of certain insects which paralyse their prey, and fill their
cellars before laying an egg. She must surely be obliged to follow the
method of the Bembex, whose larva receives, at intervals, the necessary
nourishment; the amount increasing as the larva grows. The facts confirm
this deduction. I spoke just now of the tediousness of my watching when
watching the colonies of the Philanthus. It was perhaps even more
tedious than when I was keeping an eye upon the Bembex. Before the
burrows of _Cerceris tuberculus_ and other devourers of the weevil, and
before that of the yellow-winged Sphex, the slayer of crickets, there
is plenty of distraction, owing to the busy movements of the community.
The mothers have scarcely entered the nest before they are off again,
returning quickly with fresh prey, only to set out once more. The going
and coming is almost continuous until the storehouse is full.
The burrows of the Philanthus know nothing of such animation, even in a
populous colony. In vain my vigils prolonged themselves into whole
mornings or afternoons, and only very rarely does the mother who has
entered with a bee set forth upon a second expedition. Two captures by
the same huntress is the most that I have seen in my long watches. Once
the family is provided with sufficient food for the moment the mother
postpones further hunting trips until hunting becomes necessary, and
busies herself with digging and burrowing in her underground dwelling.
Little cells are excavated, and I see the rubbish from them gradually
pushed up to the surface. With that exception there is no sign of
activity; it is as though the burrow were deserted.
To lay the nest bare is not easy. The burrow penetrates to a depth of
about three feet in a compact soil; sometimes in a vertical, sometimes
in a horizontal direction. The spade and pick, wielded by hands more
vigorous but less expert than my own, are indispensable; but the conduct
of the excavation is anything but satisfactory. At the extremity of the
long gallery--it seems as though the straw I use for sounding would
never reach the end--we finally discover the cells, egg-shaped cavities
with the longer axis horizontal. Their number and their mutual
disposition escape me.
Some already contain the cocoon--slender and translucid, like that of
the Cerceris, and, like it, recalling the shape of certain
homoeopathic phials, with oval bodies surmounted by a tapering neck.
By the extremity of the neck, which is blackened and hardened by the
dejecta of the larvæ, the cocoon is fixed to the end of the cell without
any other support. It reminds one of a short club, planted by the end of
the handle, in a line with the horizontal axis of the cell. Other cells
contain the larva in a stage more or less advanced. The grub is eating
the last victim proffered; around it lie the remains of food already
consumed. Others, again, show me a bee, a single bee, still intact, and
having an egg deposited on the under-side of the thorax. This bee
represents the first instalment of rations; others will follow as the
grub matures. My expectations are thus confirmed; as with Bembex, slayer
of Diptera, so Philanthus, killer of bees, lays her egg upon the first
body stored, and completes, at intervals, the provisioning of the cells.
The problem of the dead bee is elucidated; there remains the other
problem, of incomparable interest--Why, before they are given over to
the larvæ, are the bees robbed of their honey? I have said, and I
repeat, that the killing and emptying of the bee cannot be explained
solely by the gluttony of the Philanthus. To rob the worker of its booty
is nothing; such things are seen every day; but to slaughter it in order
to empty its stomach--no, gluttony cannot be the only motive. And as the
bees placed in the cells are squeezed dry no less than the others, the
idea occurs to me that as a beefsteak garnished with _confitures_ is not
to every one's taste, so the bee sweetened with honey may well be
distasteful or even harmful to the larvæ of the Philanthus. What would
the grub do if, replete with blood and flesh, it were to find under its
mandibles the honey-bag of the bee?--if, gnawing at random, it were to
open the bees stomach and so drench its game with syrup? Would it
approve of the mixture? Would the little ogre pass without repugnance
from the gamey flavour of a corpse to the scent of flowers? To affirm or
deny is useless. We must see. Let us see.
I take the young larvæ of the Philanthus, already well matured, but
instead of serving them with the provisions buried in their cells I
offer them game of my own catching--bees that have filled themselves
with nectar among the rosemary bushes. My bees, killed by crushing the
head, are thankfully accepted, and at first I see nothing to justify my
suspicions. Then my nurslings languish, show themselves disdainful of
their food, give a negligent bite here and there, and finally, one and
all, die beside their uncompleted meal. All my attempts miscarry; not
once do I succeed in rearing my larvæ as far as the stage of spinning
the cocoon. Yet I am no novice in my duties as dry-nurse. How many
pupils have passed through my hands and have reached the final stage in
my old sardine-boxes as well as in their native burrows! I shall draw no
conclusions from this check, which my scruples may attribute to some
unknown cause. Perhaps the atmosphere of my cabinet and the dryness of
the sand serving them for a bed have been too much for my nurslings,
whose tender skins are used to the warm moisture of the subsoil. Let us
try another method.
To decide positively whether honey is or is not repugnant to the grubs
of the Philanthus was hardly practicable by the method just explained.
The first meals consisted of flesh, and after that nothing in
particular occurred. The honey is encountered later, when the bee is
largely consumed. If hesitation and repugnance were manifested at this
point they came too late to be conclusive; the sickness of the larvæ
might be due to other causes, known or unknown. We must offer honey at
the very beginning, before artificial rearing has spoilt the grub's
appetite. To offer pure honey would, of course, be useless; no
carnivorous creature would touch it, even were it starving. I must
spread the honey on meat; that is, I must smear the dead bee with honey,
lightly varnishing it with a camel's-hair brush.
Under these conditions the problem is solved with the first few
mouthfuls. The grub, having bitten on the honeyed bee, draws back as
though disgusted; hesitates for a long time; then, urged by hunger,
begins again; tries first on one side, then on another; in the end it
refuses to touch the bee again. For a few days it pines upon its
rations, which are almost intact, then dies. As many as are subjected to
the same treatment perish in the same way.
Do they simply die of hunger in the presence of food which their
appetites reject, or are they poisoned by the small amount of honey
absorbed at the first bites? I cannot say; but, whether poisonous or
merely repugnant, the bee smeared with honey is always fatal to them; a
fact which explains more clearly than the unfavourable circumstances of
the former experiment my lack of success with the freshly killed bees.
This refusal to touch honey, whether poisonous or repugnant, is
connected with principles of alimentation too general to be a
gastronomic peculiarity of the Philanthus grub. Other carnivorous
larvæ--at least in the series of the Hymenoptera--must share it. Let us
experiment. The method need not be changed. I exhume the larvæ when in a
state of medium growth, to avoid the vicissitudes of extreme youth; I
collect the bodies of the grubs and insects which form their natural
diet and smear each body with honey, in which condition I return them to
the larvæ. A distinction is apparent: all the larvæ are not equally
suited to my experiment. Those larvæ must be rejected which are
nourished upon one single corpulent insect, as is that of the Scolia.
The grub attacks its prey at a determined point, plunges its head and
neck into the body of the insect, skilfully divides the entrails in
order to keep the remains fresh until its meal is ended, and does not
emerge from the opening until all is consumed but the empty skin.
To interrupt the larva with the object of smearing the interior of its
prey with honey is doubly objectionable; I might extinguish the
lingering vitality which keeps putrefaction at bay in the victim, and I
might confuse the delicate art of the larva, which might not be able to
recover the lode at which it was working or to distinguish between those
parts which are lawfully and properly eaten and those which must not be
consumed until a later period. As I have shown in a previous volume, the
grub of the Scolia has taught me much in this respect. The only larvæ
acceptable for this experiment are those which are fed on a number of
small insects, which are attacked without any special art, dismembered
at random, and quickly consumed. Among such larvæ I have experimented
with those provided by chance--those of various Bembeces, fed on
Diptera; those of the Palaris, whose diet consists of a large variety of
Hymenoptera; those of the Tachytus, provided with young crickets; those
of the Odynerus, fed upon larvæ of the Chrysomela; those of the
sand-dwelling Cerceris, endowed with a hecatomb of weevils. As will be
seen, both consumers and consumed offer plenty of variety. Well, in
every case their proper diet, seasoned with honey, is fatal. Whether
poisoned or disgusted, they all die in a few days.
A strange result! Honey, the nectar of the flowers, the sole diet of the
apiary under its two forms and the sole nourishment of the predatory
insect in its adult phase, is for the larva of the same insect an object
of insurmountable disgust, and probably a poison. The transfiguration of
the chrysalis surprises me less than this inversion of the appetite.
What change occurs in the stomach of the insect that the adult should
passionately seek that which the larva refuses under peril of death? It
is no question of organic debility unable to support a diet too
substantial, too hard, or too highly spiced. The grubs which consume the
larva of the Cetoniæ, for example (the Rose-chafers), those which feed
upon the leathery cricket, and those whose diet is rich in nitrobenzine,
must assuredly have complacent gullets and adaptable stomachs. Yet these
robust eaters die of hunger or poison for no greater cause than a drop
of syrup, the lightest diet imaginable, adapted to the weakness of
extreme youth, and a delicacy to the adult! What a gulf of obscurity in
the stomach of a miserable worm!
These gastronomic experiments called for a counter-proof. The
carnivorous grub is killed by honey. Is the honey-fed grub, inversely,
killed by carnivorous diet? Here, again, we must make certain
exceptions, observe a certain choice, as in the previous experiments. It
would obviously be courting a flat refusal to offer a heap of young
crickets to the larvæ of the Anthophorus and the Osmia, for example; the
honey-fed grub would not bite such food. It would be absolutely useless
to make such an experiment. We must find the equivalent of the bee
smeared with honey; that is, we must offer the larva its ordinary food
with a mixture of animal matter added. I shall experiment with albumen,
as provided by the egg of the hen; albumen being an isomer of fibrine,
which is the principal element of all flesh diet.
_Osmia tricornis_ will lend itself to my experiment better than any
other insect on account of its dry honey, or bee-bread, which is largely
formed of flowery pollen. I knead it with the albumen, graduating the
dose of the latter so that its weight largely exceeds that of the
bee-bread. Thus I obtain pastes of various degrees of consistency, but
all firm enough to support the larva without danger of immersion. With
too fluid a mixture there would be a danger of death by drowning.
Finally, on each cake of albuminous paste I install a larva of medium
growth.
This diet is not distasteful; far from it. The grubs attack it without
hesitation and devour it with every appearance of a normal appetite.
Matters could not go better if the food had not been modified according
to my recipes. All is eaten; even the portions which I feared contained
an excessive proportion of albumen. Moreover--a matter of still greater
importance--the larvæ of the Osmia fed in this manner attain their
normal growth and spin their cocoons, from which adults issue in the
following year. Despite the albuminous diet the cycle of evolution
completes itself without mishap.
What are we to conclude from all this? I confess I am embarrassed. _Omne
vivum ex ovo_, says the physiologist. All animals are carnivorous in
their first beginnings; they are formed and nourished at the expense of
the egg, in which albumen predominates. The highest, the mammals, adhere
to this diet for a considerable time; they live by the maternal milk,
rich in casein, another isomer of albumen. The gramnivorous nestling is
fed first upon worms and grubs, which are best adapted to the delicacy
of its stomach; many newly born creatures among the lower orders, being
immediately left to their own devices, live on animal diet. In this way
the original method of alimentation is continued--the method which
builds flesh out of flesh and makes blood out of blood with no chemical
processes but those of simple reconstruction. In maturity, when the
stomach is more robust, a vegetable diet may be adopted, involving a
more complex chemistry, although the food itself is more easily
obtained. To milk succeeds fodder; to the worm, seeds and grain; to the
dead or paralysed insects of the natal burrow, the nectar of flowers.
Here is a partial explanation of the double system of the Hymenoptera
with their carnivorous larvæ--the system of dead or paralysed insects
followed by honey. But here the point of interrogation, already
encountered elsewhere, erects itself once again. Why is the larva of
the Osmia, which thrives upon albumen, actually fed upon honey during
its early life? Why is a vegetable diet the rule in the hives of bees
from the very commencement, when the other members of the same series
live upon animal food?
If I were a "transformist" how I should delight in this question! Yes, I
should say: yes, by the fact of its germ every animal is originally
carnivorous. The insect in particular makes a beginning with albuminoid
materials. Many larvæ adhere to the alimentation present in the egg, as
do many adult insects also. But the struggle to fill the belly, which is
actually the struggle for life, demands something better than the
precarious chances of the chase. Man, at first an eager hunter of game,
collected flocks and became a shepherd in order to profit by his
possessions in time of dearth. Further progress inspired him to till the
earth and sow; a method which assured him of a certain living. Evolution
from the defective to the mediocre, and from the mediocre to the
abundant, has led to the resources of agriculture.
The lower animals have preceded us on the way of progress. The ancestors
of the Philanthus, in the remote ages of the lacustrian tertiary
formations, lived by capturing prey in both phases--both as larvæ and as
adults; they hunted for their own benefit as well as for the family.
They did not confine themselves to emptying the stomach of the bee, as
do their descendants to-day; they devoured the victim entire. From
beginning to end they remained carnivorous. Later there were fortunate
innovators, whose race supplanted the more conservative element, who
discovered an inexhaustible source of nourishment, to be obtained
without painful search or dangerous conflict: the saccharine exudation
of the flowers. The wasteful system of living upon prey, by no means
favourable to large populations, has been preserved for the feeble
larvæ; but the vigorous adult has abandoned it for an easier and more
prosperous existence. Thus the Philanthus of our own days was gradually
developed; thus was formed the double system of nourishment practised by
the various predatory insects which we know.
The bee has done still better; from the moment of leaving the egg it
dispenses completely with chance-won aliments. It has invented honey,
the food of its larvæ. Renouncing the chase for ever, and becoming
exclusively agricultural, this insect has acquired a degree of moral and
physical prosperity that the predatory species are far from sharing.
Hence the flourishing colonies of the Anthophoræ, the Osmiæ, the Euceræ,
the Halicti, and other makers of honey, while the hunters of prey work
in isolation; hence the societies in which the bee displays its
admirable talents, the supreme expression of instinct.
This is what I should say if I were a "transformist." All this is a
chain of highly logical deductions, and it hangs together with a certain
air of reality, such as we like to look for in a host of "transformist"
arguments which are put forward as irrefutable. Well, I make a present
of my deductive theory to whosoever desires it, and without the least
regret; I do not believe a single word of it, and I confess my profound
ignorance of the origin of the twofold system of diet.
One thing I do see more clearly after all my experiments and research:
the tactics of the Philanthus. As a witness of its ferocious feasting,
the true motive of which was unknown to me, I treated it to all the
unfavourable epithets I could think of; called it assassin, bandit,
pirate, robber of the dead. Ignorance is always abusive; the man who
does not know is full of violent affirmations and malign
interpretations. Undeceived by the facts, I hasten to apologise and
express my esteem for the Philanthus. In emptying the stomach of the bee
the mother is performing the most praiseworthy of all duties; she is
guarding her family against poison. If she sometimes kills on her own
account and abandons the body after exhausting it of honey, I dare not
call her action a crime. When the habit has once been formed of emptying
the bee's crop for the best of motives, the temptation is great to do so
with no other excuse than hunger. Moreover--who can say?--perhaps there
is always some afterthought that the larvæ might profit by the
sacrifice. Although not carried into effect the intention excuses the
act.
I therefore withdraw my abusive epithets in order to express my
admiration of the creature's maternal logic. Honey would be harmful to
the grubs. How does the mother know that honey, in which she herself
delights, is noxious to her young? To this question our knowledge has no
reply. But honey, as we have seen, would endanger the lives of the
grubs. The bees must therefore be emptied of honey before they are fed
to them. The process must be effected without wounding the victim, for
the larva must receive the latter fresh and moist; and this would be
impracticable if the insect were paralysed on account of the natural
resistance of the organs. The bee must therefore be killed outright
instead of being paralysed, otherwise the honey could not be removed.
Instantaneous death can be assured only by a lesion of the primordial
centre of life. The sting must therefore pierce the cervical ganglions;
the centre of innervation upon which the rest of the organism is
dependent. This can only be reached in one way: through the neck. Here
it is that the sting will be inserted; and here it is inserted in a
breach in the armour no larger than a pin's head. Suppress a single link
of this closely knit chain, and the Philanthus reared upon the flesh of
bees becomes an impossibility.
That honey is fatal to larvæ is a fact pregnant with consequences.
Various predatory insects feed their young with honey-makers. Such, to
my knowledge, are the _Philanthus coronatus_, Fabr., which stores its
burrows with the large Halictus; the _Philanthus raptor_, Lep., which
chases all the smaller Halictus indifferently, being itself a small
insect; the _Cerceris ornata_, Fabr., which also kills Halictus; and the
_Polaris flavipes_, Fabr., which by a strange eclecticism fills its
cells with specimens of most of the Hymenoptera which are not beyond its
powers. What do these four huntresses, and others of similar habits, do
with their victims when the crops of the latter are full of honey? They
must follow the example of the Philanthus or their offspring would
perish; they must squeeze and manipulate the dead bee until it yields up
its honey. Everything goes to prove as much; but for the actual
observation of what would be a notable proof of my theory I must trust
to the future.
CHAPTER XIV
THE GREAT PEACOCK, OR EMPEROR MOTH
It was a memorable night! I will name it the Night of the Great Peacock.
Who does not know this superb moth, the largest of all our European
butterflies[3] with its livery of chestnut velvet and its collar of
white fur? The greys and browns of the wings are crossed by a paler
zig-zag, and bordered with smoky white; and in the centre of each wing
is a round spot, a great eye with a black pupil and variegated iris,
resolving into concentric arcs of black, white, chestnut, and purplish
red.
Not less remarkable is the caterpillar. Its colour is a vague yellow. On
the summit of thinly sown tubercles crowned with a palisade of black
hairs are set pearls of a turquoise-blue. The burly brown cocoon, which
is notable for its curious tunnel of exit, like an eel-pot, is always
found at the base of an old almond-tree, adhering to the bark. The
foliage of the same tree nourishes the caterpillar.
On the morning of the 6th of May a female emerged from her cocoon in my
presence on my laboratory table. I cloistered her immediately, all damp
with the moisture of metamorphosis, in a cover of wire gauze. I had no
particular intentions regarding her; I imprisoned her from mere habit;
the habit of an observer always on the alert for what may happen.
I was richly rewarded. About nine o'clock that evening, when the
household was going to bed, there was a sudden hubbub in the room next
to mine. Little Paul, half undressed, was rushing to and fro, running,
jumping, stamping, and overturning the chairs as if possessed. I heard
him call me. "Come quick!" he shrieked; "come and see these butterflies!
Big as birds! The room's full of them!"
I ran. There was that which justified the child's enthusiasm and his
hardly hyperbolical exclamation. It was an invasion of giant
butterflies; an invasion hitherto unexampled in our house. Four were
already caught and placed in a bird-cage. Others--numbers of them--were
flying across the ceiling.
This astonishing sight recalled the prisoner of the morning to my mind.
"Put on your togs, kiddy!" I told my son; "put down your cage, and come
with me. We shall see something worth seeing."
We had to go downstairs to reach my study, which occupies the right wing
of the house. In the kitchen we met the servant; she too was bewildered
by the state of affairs. She was pursuing the huge butterflies with her
apron, having taken them at first for bats.
It seemed as though the Great Peacock had taken possession of my whole
house, more or less. What would it be upstairs, where the prisoner was,
the cause of this invasion? Happily one of the two study windows had
been left ajar; the road was open.
[Illustration: THE GREAT PEACOCK OR EMPEROR MOTH.]
Candle in hand, we entered the room. What we saw is unforgettable. With
a soft _flic-flac_ the great night-moths were flying round the
wire-gauze cover, alighting, taking flight, returning, mounting to the
ceiling, re-descending. They rushed at the candle and extinguished it
with a flap of the wing; they fluttered on our shoulders, clung to our
clothing, grazed our faces. My study had become a cave of a necromancer,
the darkness alive with creatures of the night! Little Paul, to reassure
himself, held my hand much tighter than usual.
How many were there? About twenty. To these add those which had strayed
into the kitchen, the nursery, and other rooms in the house, and the
total must have been nearly forty. It was a memorable sight--the Night
of the Great Peacock! Come from all points of the compass, warned I know
not how, here were forty lovers eager to do homage to the maiden
princess that morning born in the sacred precincts of my study.
For the time being I troubled the swarm of pretenders no further. The
flame of the candle endangered the visitors; they threw themselves into
it stupidly and singed themselves slightly. On the morrow we could
resume our study of them, and make certain carefully devised
experiments.
To clear the ground a little for what is to follow, let me speak of what
was repeated every night during the eight nights my observations lasted.
Every night, when it was quite dark, between eight and ten o'clock, the
butterflies arrived one by one. The weather was stormy; the sky heavily
clouded; the darkness was so profound that out of doors, in the garden
and away from the trees, one could scarcely see one's hand before one's
face.
In addition to such darkness as this there were certain difficulties of
access. The house is hidden by great plane-trees; an alley densely
bordered with lilacs and rose-trees make a kind of outer vestibule to
the entrance; it is protected from the _mistral_ by groups of pines and
screens of cypress. A thicket of evergreen shrubs forms a rampart at a
few paces from the door. It was across this maze of leafage, and in
absolute darkness, that the butterflies had to find their way in order
to attain the end of their pilgrimage.
Under such conditions the screech-owl would not dare to forsake its
hollow in the olive-tree. The butterfly, better endowed with its faceted
eyes than the owl with its single pupils, goes forward without
hesitation, and threads the obstacles without contact. So well it
directs its tortuous flight that, in spite of all the obstacles to be
evaded, it arrives in a state of perfect freshness, its great wings
intact, without the slightest flaw. The darkness is light enough for the
butterfly.
Even if we suppose it to be sensitive to rays unknown to the ordinary
retina, this extraordinary sight could not be the sense that warns the
butterfly at a distance and brings it hastening to the bride. Distance
and the objects interposed make the suggestion absurd.
Moreover, apart from illusory refractions, of which there is no question
here, the indications of light are precise; one goes straight to the
object seen. But the butterfly was sometimes mistaken: not in the
general direction, but concerning the precise position of the attractive
object. I have mentioned that the nursery on the other side of the house
to my study, which was the actual goal of the visitors, was full of
butterflies before a light was taken into it. These were certainly
incorrectly informed. In the kitchen there was the same crowd of
seekers gone astray; but there the light of a lamp, an irresistible
attraction to nocturnal insects, might have diverted the pilgrims.
Let us consider only such areas as were in darkness. There the pilgrims
were numerous. I found them almost everywhere in the neighbourhood of
their goal. When the captive was in my study the butterflies did not all
enter by the open window, the direct and easy way, the captive being
only a few yards from the window. Several penetrated the house
downstairs, wandered through the hall, and reached the staircase, which
was barred at the top by a closed door.
These data show us that the visitors to the wedding-feast did not go
straight to their goal as they would have done were they attracted by
any kind of luminous radiations, whether known or unknown to our
physical science. Something other than radiant energy warned them at a
distance, led them to the neighbourhood of the precise spot, and left
the final discovery to be made after a vague and hesitating search. The
senses of hearing and smell warn us very much in this way; they are not
precise guides when we try to determine exactly the point of origin of a
sound or smell.
What sense is it that informs this great butterfly of the whereabouts of
his mate, and leads him wandering through the night? What organ does
this sense affect? One suspects the antennæ; in the male butterfly they
actually seem to be sounding, interrogating empty space with their long
feathery plumes. Are these splendid plumes merely items of finery, or do
they really play a part in the perception of the effluvia which guide
the lover? It seemed easy, on the occasion I spoke of, to devise a
conclusive experiment.
On the morrow of the invasion I found in my study eight of my nocturnal
visitors. They were perched, motionless, upon the cross-mouldings of the
second window, which had remained closed. The others, having concluded
their ballet by about ten o'clock at night, had left as they had
entered, by the other window, which was left open night and day. These
eight persevering lovers were just what I required for my experiment.
With a sharp pair of scissors, and without otherwise touching the
butterflies, I cut off their antennæ near the base. The victims barely
noticed the operation. None moved; there was scarcely a flutter of the
wings. Their condition was excellent; the wound did not seem to be in
the least serious. They were not perturbed by physical suffering, and
would therefore be all the better adapted to my designs. They passed the
rest of the day in placid immobility on the cross-bars of the window.
A few other arrangements were still to be made. In particular it was
necessary to change the scene; not to leave the female under the eyes of
the mutilated butterflies at the moment of resuming their nocturnal
flight; the difficulty of the search must not be lessened. I therefore
removed the cage and its captive, and placed it under a porch on the
other side of the house, at a distance of some fifty paces from my
study.
At nightfall I went for a last time to inspect my eight victims. Six had
left by the open window; two still remained, but they had fallen on the
floor, and no longer had the strength to recover themselves if turned
over on their backs. They were exhausted, dying. Do not accuse my
surgery, however. Such early decease was observed repeatedly, with no
intervention on my part.
Six, in better condition, had departed. Would they return to the call
that attracted them the night before? Deprived of their antennæ, would
they be able to find the captive, now placed at a considerable distance
from her original position?
The cage was in darkness, almost in the open air. From time to time I
visited it with a net and lantern. The visitors were captured,
inspected, and immediately released in a neighbouring room, of which I
closed the door. This gradual elimination allowed me to count the
visitors exactly without danger of counting the same butterfly more than
once. Moreover, the provisional prison, large and bare, in no wise
harmed or endangered the prisoners; they found a quiet retreat there and
ample space. Similar precautions were taken during the rest of my
experiments.
After half-past ten no more arrived. The reception was over. Total,
twenty-five males captured, of which one only was deprived of its
antennæ. So of the six operated on earlier in the day, which were strong
enough to leave my study and fly back to the fields, only one had
returned to the cage. A poor result, in which I could place no
confidence as proving whether the antennæ did or did not play a
directing part. It was necessary to begin again upon a larger scale.
Next morning I visited the prisoners of the day before. What I saw was
not encouraging. A large number were scattered on the ground, almost
inert. Taken between the fingers, several of them gave scarcely a sign
of life. Little was to be hoped from these, it would seem. Still, I
determined to try; perhaps they would regain their vigour at the lover's
hour.
The twenty-four prisoners were all subjected to the amputation of their
antennæ. The one operated on the day before was put aside as dying or
nearly so. Finally the door of the prison was left open for the rest of
the day. Those might leave who could; those could join in the carnival
who were able. In order to put those that might leave the room to the
test of a search, the cage, which they must otherwise have encountered
at the threshold, was again removed, and placed in a room of the
opposite wing, on the ground floor. There was of course free access to
this room.
Of the twenty-four lacking their antennæ sixteen only left the room.
Eight were powerless to do so; they were dying. Of the sixteen, how many
returned to the cage that night? Not one. My captives that night were
only seven, all new-comers, all wearing antennæ. This result seemed to
prove that the amputation of the antennæ was a matter of serious
significance. But it would not do to conclude as yet: one doubt
remained.
"A fine state I am in! How shall I dare to appear before the other
dogs?" said Mouflard, the puppy whose ears had been pitilessly docked.
Had my butterflies apprehensions similar to Master Mouflard's? Deprived
of their beautiful plumes, were they ashamed to appear in the midst of
their rivals, and to prefer their suits? Was it confusion on their part,
or want of guidance? Was it not rather exhaustion after an attempt
exceeding the duration of an ephemeral passion? Experience would show
me.
On the fourth night I took fourteen new-comers and set them apart as
they came in a room in which they spent the night. On the morrow,
profiting by their diurnal immobility, I removed a little of the hair
from the centre of the corselet or neck. This slight tonsure did not
inconvenience the insects, so easily was the silky fur removed, nor did
it deprive them of any organ which might later on be necessary in the
search for the female. To them it was nothing; for me it was the
unmistakable sign of a repeated visit.
This time there were none incapable of flight. At night the fourteen
shavelings escaped into the open air. The cage, of course, was again in
a new place. In two hours I captured twenty butterflies, of whom two
were tonsured; no more. As for those whose antennæ I had amputated the
night before, not one reappeared. Their nuptial period was over.
Of fourteen marked by the tonsure two only returned. Why did the other
twelve fail to appear, although furnished with their supposed guides,
their antennæ? To this I can see only one reply: that the Great Peacock
is promptly exhausted by the ardours of the mating season.
With a view to mating, the sole end of its life, the great moth is
endowed with a marvellous prerogative. It has the power to discover the
object of its desire in spite of distance, in spite of obstacles. A few
hours, for two or three nights, are given to its search, its nuptial
flights. If it cannot profit by them, all is ended; the compass fails,
the lamp expires. What profit could life hold henceforth? Stoically the
creature withdraws into a corner and sleeps the last sleep, the end of
illusions and the end of suffering.
The Great Peacock exists as a butterfly only to perpetuate itself. It
knows nothing of food. While so many others, joyful banqueters, fly from
flower to flower, unrolling their spiral trunks to plunge them into
honeyed blossoms, this incomparable ascetic, completely freed from the
servitude of the stomach, has no means of restoring its strength. Its
buccal members are mere vestiges, useless simulacra, not real organs
able to perform their duties. Not a sip of honey can ever enter its
stomach; a magnificent prerogative, if it is not long enjoyed. If the
lamp is to burn it must be filled with oil. The Great Peacock renounces
the joys of the palate; but with them it surrenders long life. Two or
three nights--just long enough to allow the couple to meet and mate--and
all is over; the great butterfly is dead.
What, then, is meant by the non-appearance of those whose antennæ I
removed? Did they prove that the lack of antennæ rendered them incapable
of finding the cage in which the prisoner waited? By no means. Like
those marked with the tonsure, which had undergone no damaging
operation, they proved only that their time was finished. Mutilated or
intact, they could do no more on account of age, and their absence meant
nothing. Owing to the delay inseparable from the experiment, the part
played by the antennæ escaped me. It was doubtful before; it remained
doubtful.
My prisoner under the wire-gauze cover lived for eight days. Every night
she attracted a swarm of visitors, now to one part of the house, now to
another. I caught them with the net and released them as soon as
captured in a closed room, where they passed the night. On the next day
they were marked, by means of a slight tonsure on the thorax.
The total number of butterflies attracted on these eight nights amounted
to a hundred and fifty; a stupendous number when I consider what
searches I had to undertake during the two following years in order to
collect the specimens necessary to the continuation of my investigation.
Without being absolutely undiscoverable, in my immediate neighbourhood
the cocoons of the Great Peacock are at least extremely rare, as the
trees on which they are found are not common. For two winters I visited
all the decrepit almond-trees at hand, inspected them all at the base of
the trunk, under the jungle of stubborn grasses and undergrowth that
surrounded them; and how often I returned with empty hands! Thus my
hundred and fifty butterflies had come from some little distance;
perhaps from a radius of a mile and a quarter or more. How did they
learn of what was happening in my study?
Three agents of information affect the senses at a distance: sight,
sound, and smell. Can we speak of vision in this connection? Sight could
very well guide the arrivals once they had entered the open window; but
how could it help them out of doors, among unfamiliar surroundings? Even
the fabulous eye of the lynx, which could see through walls, would not
be sufficient; we should have to imagine a keenness of vision capable of
annihilating leagues of space. It is needless to discuss the matter
further; sight cannot be the guiding sense.
Sound is equally out of the question. The big-bodied creature capable of
calling her mates from such a distance is absolutely mute, even to the
most sensitive ear. Does she perhaps emit vibrations of such delicacy or
rapidity that only the most sensitive microphone could appreciate them?
The idea is barely possible; but let us remember that the visitors must
have been warned at distances of some thousands of yards. Under these
conditions it is useless to think of acoustics.
Smell remains. Scent, better than any other impression in the domain of
our senses, would explain the invasion of butterflies, and their
difficulty at the very last in immediately finding the object of their
search. Are there effluvia analogous to what we call odour: effluvia of
extreme subtlety, absolutely imperceptible to us, yet capable of
stimulating a sense-organ far more sensitive than our own? A simple
experiment suggested itself. I would mask these effluvia, stifle them
under a powerful, tenacious odour, which would take complete possession
of the sense-organ and neutralise the less powerful impression.
I began by sprinkling naphthaline in the room intended for the reception
of the males that evening. Beside the female, inside the wire-gauze
cover, I placed a large capsule full of the same substance. When the
hour of the nocturnal visit arrived I had only to stand at the door of
the room to smell a smell as of a gas-works. Well, my artifice failed.
The butterflies arrived as usual, entered the room, traversed its
gas-laden atmosphere, and made for the wire-gauze cover with the same
certainty as in a room full of fresh air.
My confidence in the olfactory theory was shaken. Moreover, I could not
continue my experiments. On the ninth day, exhausted by her fruitless
period of waiting, the female died, having first deposited her barren
eggs upon the woven wire of her cage. Lacking a female, nothing could be
done until the following year.
I determined next time to take suitable precautions and to make all
preparations for repeating at will the experiments already made and
others which I had in mind. I set to work at once, without delay.
In the summer I began to buy caterpillars at a halfpenny apiece.
The market was in the hands of some neighbouring urchins, my habitual
providers. On Friday, free of the terrors of grammar, they scoured the
fields, finding from time to time the Great Peacock caterpillar, and
bringing it to me clinging to the end of a stick. They did not dare to
touch it, poor little imps! They were thunderstruck at my audacity when
I seized it in my fingers as they would the familiar silkworm.
Reared upon twigs of the almond-tree, my menagerie soon provided me with
magnificent cocoons. In winter assiduous search at the base of the
native trees completed my collection. Friends interested in my
researches came to my aid. Finally, after some trouble, what with an
open market, commercial negotiations, and searching, at the cost of many
scratches, in the undergrowth, I became the owner of an assortment of
cocoons of which twelve, larger and heavier than the rest, announced
that they were those of females.
Disappointment awaited me. May arrived; a capricious month which set my
preparations at naught, troublesome as these had been. Winter returned.
The _mistral_ shrieked, tore the budding leaves of the plane-trees, and
scattered them over the ground. It was cold as December. We had to
light fires in the evening, and resume the heavy clothes we had begun to
leave off.
My butterflies were too sorely tried. They emerged late and were torpid.
Around my cages, in which the females waited--to-day one, to-morrow
another, according to the order of their birth--few males or none came
from without. Yet there were some in the neighbourhood, for those with
large antennæ which issued from my collection of cocoons were placed in
the garden directly they had emerged, and were recognised. Whether
neighbours or strangers, very few came, and those without enthusiasm.
For a moment they entered, then disappeared and did not reappear. The
lovers were as cold as the season.
Perhaps, too, the low temperature was unfavourable to the informing
effluvia, which might well be increased by heat and lessened by cold as
is the case with many odours. My year was lost. Research is
disappointing work when the experimenter is the slave of the return and
the caprices of a brief season of the year.
For the third time I began again. I reared caterpillars; I scoured the
country in search of cocoons. When May returned I was tolerably
provided. The season was fine, responding to my hopes. I foresaw the
affluence of butterflies which had so impressed me at the outset, when
the famous invasion occurred which was the origin of my experiments.
Every night, by squadrons of twelve, twenty, or more, the visitors
appeared. The female, a strapping, big-bellied matron, clung to the
woven wire of the cover. There was no movement on her part; not even a
flutter of the wings. One would have thought her indifferent to all
that occurred. No odour was emitted that was perceptible to the most
sensitive nostrils of the household; no sound that the keenest ears of
the household could perceive. Motionless, recollected, she waited.
The males, by twos, by threes and more, fluttered upon the dome of the
cover, scouring over it quickly in all directions, beating it
continually with the ends of their wings. There were no conflicts
between rivals. Each did his best to penetrate the enclosure, without
betraying any sign of jealousy of the others. Tiring of their fruitless
attempts, they would fly away and join the dance of the gyrating crowd.
Some, in despair, would escape by the open window: new-comers would
replace them: and until ten o'clock or thereabouts the wire dome of the
cover would be the scene of continual attempts at approach, incessantly
commencing, quickly wearying, quickly resumed.
Every night the position of the cage was changed. I placed it north of
the house and south; on the ground-floor and the first floor; in the
right wing of the house, or fifty yards away in the left wing; in the
open air, or hidden in some distant room. All these sudden removals,
devised to put the seekers off the scent, troubled them not at all. My
time and my pains were wasted, so far as deceiving them was concerned.
The memory of places has no part in the finding of the female. For
instance, the day before the cage was installed in a certain room. The
males visited the room and fluttered about the cage for a couple of
hours, and some even passed the night there. On the following day, at
sunset, when I moved the cage, all were out of doors. Although their
lives are so ephemeral, the youngest were ready to resume their
nocturnal expeditions a second and even a third time. Where did they
first go, these veterans of a day?
They knew precisely where the cage had been the night before. One would
have expected them to return to it, guided by memory; and that not
finding it they would go out to continue their search elsewhere. No;
contrary to my expectation, nothing of the kind appeared. None came to
the spot which had been so crowded the night before; none paid even a
passing visit. The room was recognised as an empty room, with no
previous examination, such as would apparently be necessary to
contradict the memory of the place. A more positive guide than memory
called them elsewhere.
Hitherto the female was always visible, behind the meshes of the
wire-gauze cover. The visitors, seeing plainly in the dark night, must
have been able to see her by the vague luminosity of what for us is the
dark. What would happen if I imprisoned her in an opaque receptacle?
Would not such a receptacle arrest or set free the informing effluvia
according to its nature?
Practical physics has given us wireless telegraphy by means of the
Hertzian vibrations of the ether. Had the Great Peacock butterfly
outstripped and anticipated mankind in this direction? In order to
disturb the whole surrounding neighbourhood, to warn pretenders at a
distance of a mile or more, does the newly emerged female make use of
electric or magnetic waves, known or unknown, that a screen of one
material would arrest while another would allow them to pass? In a word,
does she, after her fashion, employ a system of wireless telegraphy? I
see nothing impossible in this; insects are responsible for many
inventions equally marvellous.
Accordingly I lodged the female in boxes of various materials; boxes of
tin-plate, wood, and cardboard. All were hermetically closed, even
sealed with a greasy paste. I also used a glass bell resting upon a
base-plate of glass.
Under these conditions not a male arrived; not one, though the warmth
and quiet of the evening were propitious. Whatever its nature, whether
of glass, metal, card, or wood, the closed receptacle was evidently an
insuperable obstacle to the warning effluvia.
A layer of cotton-wool two fingers in thickness had the same result. I
placed the female in a large glass jar, and laced a piece of thin cotton
batting over the mouth for a cover; this again guarded the secret of my
laboratory. Not a male appeared.
But when I placed the females in boxes which were imperfectly closed, or
which had chinks in their sides, or even hid them in a drawer or a
cupboard, I found the males arrived in numbers as great as when the
object of their search lay in the cage of open wire-work freely exposed
on a table. I have a vivid memory of one evening when the recluse was
hidden in a hat-box at the bottom of a wall-cupboard. The arrivals went
straight to the closed doors, and beat them with their wings, _toc-toc_,
trying to enter. Wandering pilgrims, come from I know not where, across
fields and meadows, they knew perfectly what was behind the doors of the
cupboard.
So we must abandon the idea that the butterfly has any means of
communication comparable to our wireless telegraphy, as any kind of
screen, whether a good or a bad conductor, completely stops the signals
of the female. To give them free passage and allow them to penetrate to
a distance one condition is indispensable: the enclosure in which the
captive is confined must not be hermetically sealed; there must be a
communication between it and the outer air. This again points to the
probability of an odour, although this is contradicted by my experiment
with the naphthaline.
My cocoons were all hatched, and the problem was still obscure. Should I
begin all over again in the fourth year? I did not do so, for the reason
that it is difficult to observe a nocturnal butterfly if one wishes to
follow it in all its intimate actions. The lover needs no light to
attain his ends; but my imperfect human vision cannot penetrate the
darkness. I should require a candle at least, and a candle would be
constantly extinguished by the revolving swarm. A lantern would obviate
these eclipses, but its doubtful light, interspersed with heavy shadows,
by no means commends it to the scruples of an observer, who must see,
and see well.
Moreover, the light of a lamp diverts the butterflies from their object,
distracts them from their affairs, and seriously compromises the success
of the observer. The moment they enter, they rush frantically at the
flame, singe their down, and thereupon, terrified by the heat, are of no
profit to the observer. If, instead of being roasted, they are held at a
distance by an envelope of glass, they press as closely as they can to
the flame, and remain motionless, hypnotised.
[Illustration: THE GREAT PEACOCK MOTH. THE PILGRIMS DIVERTED BY THE
LIGHT OF A LAMP.]
One night, the female being in the dining-room, on the table, facing the
open window, a petroleum lamp, furnished with a large reflector in
opaline glass, was hanging from the ceiling. The arrivals alighted on
the dome of the wire-gauze cover, crowding eagerly about the
prisoner; others, saluting her in passing, flew to the lamp, circled
round it a few times, and then, fascinated by the luminous splendour
radiating from the opal cone of light, clung there motionless under the
reflector. Already the children were raising their hands to seize them.
"Leave them," I said, "leave them. Let us be hospitable: do not disturb
the pilgrims who have come to the tabernacle of the light."
During the whole evening not one of them moved. Next day they were still
there. The intoxication of the light had made them forget the
intoxication of love.
With creatures so madly in love with the light precise and prolonged
experimentation is impracticable the moment the observer requires
artificial light. I renounced the Great Peacock and its nocturnal
habits. I required a butterfly with different habits; equally notable as
a lover, but seeking out the beloved by day.
Before going on to speak of my experiments with a subject fulfilling
these conditions, let me break the chronological order of my record in
order to say a few words concerning another insect, which appeared after
I had completed these inquiries. I refer to the Lesser Peacock (_Attacus
pavonia minor_, Lin.).
Some one brought me, from what locality I do not know, a superb cocoon
enveloped in an ample wrapping of white silk. From this covering, which
lay in large irregular folds, the chrysalis was easily detached; in
shape like that of the Great Peacock, but considerably less in size. The
anterior extremity, which is defended by an arrangement of fine twigs,
converging, and free at the converging ends, forming a device not unlike
an eel-pot, which presents access to the chrysalis while allowing the
butterfly to emerge without breaking the defence, indicated a relative
of the great nocturnal butterfly; the silk-work denoted a spinning
caterpillar.
Towards the end of March this curious cocoon yielded up a female of the
Lesser Peacock, which was immediately sequestered under a wire-gauze
cover in my study. I opened the window to allow news of the event to
reach the surrounding country, and left it open so that such visitors as
presented themselves should find free access to the cage. The captive
clung to the wire gauze and did not move for a week.
She was a superb creature, this prisoner of mine, with her suit of brown
velvet, crossed by undulating lines. The neck was surrounded by white
fur; there was a carmine spot at the extremity of the upper wings, and
four great eyes in which were grouped, in concentric crescents, black,
white, red, and yellow ochre: almost the colouring of the Great Peacock,
but more vivid. Three or four times in my life I had encountered this
butterfly, so remarkable for its size and its costume. The cocoon I had
recently seen for the first time; the male I had never seen. I only knew
that, according to the books, it was half the size of the female, and
less vividly coloured, with orange-yellow on the lower wings.
Would he appear, the elegant unknown, with waving plumes; the butterfly
I had never yet seen, so rare does the Lesser Peacock seem to be in our
country? Would he, in some distant hedge, receive warning of the bride
who waited on my study table? I dared to hope it, and I was right. He
arrived even sooner than I had hoped.
Noon struck as we were sitting down to table, when little Paul, delayed
by his absorption in the expected event, suddenly ran to rejoin us, his
cheeks glowing. Between his fingers we saw the fluttering wings of a
handsome butterfly, caught but a moment before, while it was hovering in
front of my study. He showed it me, questioning me with his eyes.
"Aha!" I cried, "this is precisely the pilgrim we are waiting for. Fold
your napkin and come and see what happens. We will dine later."
Dinner was forgotten before the marvels that came to pass. With
inconceivable punctuality the butterflies hastened to meet the magical
call of the captive. With tortuous flight they arrived one by one. All
came from the north. This detail is significant. A week earlier there
had been a savage return of the winter. The _bise_ blew tempestuously,
killing the early almond blossom. It was one of those ferocious storms
which in the South commonly serve as a prelude to the spring. But the
temperature had now suddenly softened, although the wind still blew from
the north.
Now on this first occasion all the butterflies hastening to the prisoner
entered the garden from the north. They followed the direction of the
wind; not one flew against it. If their guide was a sense of smell like
ours, if they were guided by fragrant atoms suspended in the air, they
should have arrived in the opposite direction. Coming from the south, we
might believe them to be warned by effluvia carried on the wind; coming
from the north in time of _mistral_, that resistless sweeper of earth
and air, how can we suppose that they had perceived, at a remote
distance, what we will call an odour? The idea of a flow of odoriferous
atoms in a direction contrary to that of the aerial torrent seems to me
inadmissible.
For two hours, under a radiant sun, the visitors came and went before
the outer wall of the study. Most of them sought for a long time,
exploring the wall, flying on a level with the ground. To see them thus
hesitating you would say that they were puzzled to find the exact
position of the lure which called them. Although they had come from such
a distance without a mistake, they seemed imperfectly informed once they
were on the spot. Nevertheless, sooner or later they entered the room
and saluted the captive, without showing any great ardour. At two
o'clock all was over. Ten butterflies had arrived.
During the whole week, and always about noon, at the hour of the
brightest sunlight, the butterflies arrived, but in decreasing numbers.
The total approached forty. I thought it useless to repeat experiments
which would add nothing to what I had already learned. I will confine
myself to stating two facts. In the first place, the Lesser Peacock is
diurnal; that is to say, it celebrates its mating under the dazzling
brilliance of noon. It needs the full force of the sunlight. The Great
Peacock, on the contrary, which it so closely resembles both in its
adult form and the work of its caterpillar, requires the darkness of the
first hours of the night. Who can explain this strange contrast in
habits?
In the second place, a powerful current of air, sweeping away in a
contrary direction all particles that might inform the sense of smell,
does not prevent the butterflies from arriving from a direction opposite
to that taken by the effluvial stream, as we understand such matters.
To continue: I needed a diurnal moth or butterfly: not the Lesser
Peacock, which came too late, when I had nothing to ask of it, but
another, no matter what, provided it was a prompt guest at the wedding
feast. Was I to find such an insect?
CHAPTER XV
THE OAK EGGAR, OR BANDED MONK
Yes: I was to find it. I even had it already in my possession. An urchin
of seven years, with an alert countenance, not washed every day, bare
feet, and dilapidated breeches supported by a piece of string, who
frequented the house as a dealer in turnips and tomatoes, arrived one
day with his basket of vegetables. Having received the few halfpence
expected by his mother as the price of the garden-stuff, and having
counted them one by one into the hollow of his hand, he took from his
pocket an object which he had discovered the day before beneath a hedge
when gathering greenstuff for his rabbits.
"And this--will you have this?" he said, handing me the object. "Why,
certainly I will have it. Try to find me more, as many as you can, and
on Sunday you shall have lots of rides on the wooden horses. In the
meantime here is a penny for you. Don't forget it when you make up your
accounts; don't mix it with your turnip-money; put it by itself."
Beaming with satisfaction at such wealth, little touzle-head promised to
search industriously, already foreseeing a fortune.
When he had gone I examined the thing. It was worth examination. It was
a fine cocoon, thick and with blunt ends, very like a silkworm's cocoon,
firm to the touch and of a tawny colour. A brief reference to the
text-books almost convinced me that this was a cocoon of the _Bombyx
quercus_.[4] If so, what a find! I could continue my inquiry and perhaps
confirm what my study of the Great Peacock had made me suspect.
The Bombyx of the oak-tree is, in fact, a classic moth; indeed, there is
no entomological text-book but speaks of its exploits at mating-time. It
is said that a female emerged from the pupa in captivity, in the
interior of an apartment, and even in a closed box. It was far from the
country, amidst the tumult of a large city. Nevertheless, the event was
known to those concerned in the woods and meadows. Guided by some
mysterious compass, the males arrived, hastening from the distant
fields; they went to the box, fluttered against it, and flew to and fro
in the room.
These marvels I had learned by reading; but to see such a thing with
one's own eyes, and at the same time to devise experiments, is quite
another thing. What had my penny bargain in store for me? Would the
famous Bombyx issue from it?
Let us call it by its other name, the Banded Monk. This original name of
Monk was suggested by the costume of the male; a monk's robe of a modest
rusty red. But in the case of the female the brown fustian gives place
to a beautiful velvet, with a pale transversal band and little white
eyes on the fore pair of wings.
The Monk is not a common butterfly which can be caught by any one who
takes out a net at the proper season. I have never seen it around our
village or in the solitude of my grounds during a residence of twenty
years. It is true that I am not a fervent butterfly-catcher; the dead
insect of the collector's cabinet has little interest for me; I must
have it living, in the exercise of its functions. But although I have
not the collector's zeal I have an attentive eye to all that flies or
crawls in the fields. A butterfly so remarkable for its size and
colouring would never have escaped my notice had I encountered it.
The little searcher whom I had enticed by a promise of rides upon wooden
horses never made a second find. For three years I requisitioned friends
and neighbours, and especially their children, sharp-sighted snappers-up
of trifles; I myself hunted often under heaps of withered leaves; I
inspected stone-heaps and visited hollow tree-trunks. Useless pains; the
precious cocoon was not to be found. It is enough to say that the Banded
Monk is extremely rare in my neighbourhood. The importance of this fact
will presently appear.
As I suspected, my cocoon was truly that of the celebrated Oak Eggar. On
the 20th of August a female emerged from it: corpulent, big-bellied,
coloured like the male, but lighter in hue. I placed her under the usual
wire cover in the centre of my laboratory table, littered as it was with
books, bottles, trays, boxes, test-tubes, and other apparatus. I have
explained the situation in speaking of the Great Peacock. Two windows
light the room, both opening on the garden. One was closed, the other
open day and night. The butterfly was placed in the shade, between the
lines of the two windows, at a distance of 12 or 15 feet.
The rest of that day and the next went by without any occurrence worthy
of notice. Hanging by the feet to the front of the wire cover, on the
side nearest to the light, the prisoner was motionless, inert. There was
no oscillation of the wings, no tremor of the antennæ, the female of the
Great Peacock behaved in a similar fashion.
The female Bombyx gradually matured, her tender tissues gradually
becoming firmer. By some process of which our scientists have not the
least idea she elaborated a mysterious lure which would bring her lovers
from the four corners of the sky. What was happening in this big-bellied
body; what transmutations were accomplished, thus to affect the whole
countryside?
On the third day the bride was ready. The festival opened brilliantly. I
was in the garden, already despairing of success, for the days were
passing and nothing had occurred, when towards three in the afternoon,
the weather being very hot and the sun radiant, I perceived a crowd of
butterflies gyrating in the embrasure of the open window.
The lovers had at last come to visit their lady. Some were emerging from
the room, others were entering it; others, clinging to the wall of the
house, were resting as though exhausted by a long journey. I could see
others approaching in the distance, flying over the walls, over the
screens of cypress. They came from all directions, but at last with
decreasing frequency. I had missed the opening of the convocation, and
now the gathering was almost complete.
I went indoors and upstairs. This time, in full daylight and without
losing a detail, I witnessed once more the astonishing spectacle to
which the great nocturnal butterfly had first introduced me. The study
contained a cloud of males, which I estimated, at a glance, as being
about sixty in number, so far as the movement and confusion allowed me
to count them at all. After circling a few times over the cage many of
them went to the open window, but returned immediately to recommence
their evolutions. The most eager alighted on the cover, trampling on one
another, jostling one another, trying to get the best places. On the
other side of the barrier the captive, her great body hanging against
the wire, waited immovable. She betrayed not a sign of emotion in the
face of this turbulent swarm.
Going and entering, perched on the cover or fluttering round the room,
for more than three hours they continued their frenzied saraband. But
the sun was sinking, and the temperature was slowly falling. The ardour
of the butterflies also cooled. Many went out not to return. Others took
up their positions to wait for the gaieties of the following day; they
clung to the cross-bars of the closed window as the males of the Great
Peacock had done. The rejoicings were over for the day. They would
certainly be renewed on the morrow, since the courtship was without
result on account of the barrier of the wire-gauze cover.
But, alas I to my great disappointment, they were not resumed, and the
fault was mine. Late in the day a Praying Mantis was brought to me,
which merited attention on account of its exceptionally small size.
Preoccupied with the events of the afternoon, and absent-minded, I
hastily placed the predatory insect under the same cover as the moth.
It did not occur to me for a moment that this cohabitation could lead to
any harm. The Mantis was so slender, and the other so corpulent!
Alas! I little knew the fury of carnage animating the creature that
wielded those tiny grappling-irons! Next morning I met with a
disagreeable surprise: I found the little Mantis devouring the great
moth. The head and the fore part of the thorax had already disappeared.
Horrible creature! at what an evil hour you came to me! Goodbye to my
researches, the plans which I had caressed all night in my imagination!
For three years for lack of a subject, I was unable to resume them.
Bad luck, however, was not to make me forget the little I had learned.
On one single occasion about sixty males had arrived. Considering the
rarity of the Oak Eggar, and remembering the years of fruitless search
on the part of my helpers and myself, this number was no less than
stupefying. The undiscoverable had suddenly become multitudinous at the
call of the female.
Whence did they come? From all sides, and undoubtedly from considerable
distances. During my prolonged searches every bush and thicket and heap
of stones in my neighbourhood had become familiar to me, and I can
assert that the Oak Eggar was not to be found there. For such a swarm to
collect as I found in my laboratory the moths must have come from all
directions, from the whole district, and within a radius that I dare not
guess at.
Three years went by and by chance two more cocoons of the Monk or Oak
Eggar again fell into my hands. Both produced females, at an interval of
a few days towards the middle of August; so that I was able to vary and
repeat my experiments.
I rapidly repeated the experiments which had given me such positive
results in the instance of the Great Peacock moth. The pilgrims of the
day were no less skilful at finding their mates than the pilgrims of the
night. They laughed at all my tricks. Infallibly they found the
prisoners in their wire-gauze prisons, no matter in what part of the
house they were placed; they discovered them in the depths of a
wall-cupboard; they divined the secret of all manner of boxes, provided
these were not rigorously air-tight. They came no longer when the box
was hermetically sealed. So far this was only a repetition of the feats
of the Great Peacock.
A box perfectly closed, so that the air contained therein had no
communication with the external atmosphere, left the male in complete
ignorance of the recluse. Not a single one arrived, even when the box
was exposed and plain to see on the window-sill. Thus the idea of
strongly scented effluvia, which are cut off by screens of wood, metal,
card, glass, or what not, returns with double force.
I have shown that the great nocturnal moth was not thrown off the scent
by the powerful odour of naphthaline, which I thought would mask the
extra-subtle emanations of the female, which were imperceptible to human
olfactory organs. I repeated the experiment with the Oak Eggar. This
time I used all the resources of scent and stench that my knowledge of
drugs would permit.
A dozen saucers were arranged, some in the interior of the wire-gauze
cover, the prison of the female, and some around it, in an unbroken
circle. Some contained naphthaline; others the essential oil of
spike-lavender; others petroleum, and others a solution of alkaline
sulphur giving off a stench of rotten eggs. Short of asphyxiating the
prisoner I could do no more. These arrangements were made in the
morning, so that the room should be saturated when the congregation of
lovers should arrive.
In the afternoon the laboratory was filled with the most abominable
stench, in which the penetrating aroma of spike-lavender and the stink
of sulphuretted hydrogen were predominant. I must add that tobacco was
habitually smoked in this room, and in abundance. The concerted odours
of a gas-works, a smoking-room, a perfumery, a petroleum well, and a
chemical factory--would they succeed in confusing the male moths?
By no means. About three o'clock the moths arrived in as great numbers
as usual. They went straight to the cage, which I had covered with a
thick cloth in order to add to their difficulties. Seeing nothing when
once they had entered, and immersed in an extraordinary atmosphere in
which any subtle fragrance should have been annihilated, they
nevertheless made straight for the prisoner, and attempted to reach her
by burrowing under the linen cloth. My artifice had no result.
After this set-back, so obvious in its consequences, which only repeated
the lesson of the experiments made with naphthaline when my subject was
the Great Peacock, I ought logically to have abandoned the theory that
the moths are guided to their wedding festivities by means of strongly
scented effluvia. That I did not do so was due to a fortuitous
observation. Chance often has a surprise in store which sets us on the
right road when we have been seeking it in vain.
One afternoon, while trying to determine whether sight plays any part in
the search for the female once the males had entered the room, I placed
the female in a bell-glass and gave her a slender twig of oak with
withered leaves as a support. The glass was set upon a table facing the
open window. Upon entering the room the moths could not fail to see the
prisoner, as she stood directly in the way. The tray, containing a layer
of sand, on which the female had passed the preceding day and night,
covered with a wire-gauze dish-cover, was in my way. Without
premeditation I placed it at the other end of the room on the floor, in
a corner where there was but little light. It was a dozen yards away
from the window.
The result of these preparations entirely upset my preconceived ideas.
None of the arrivals stopped at the bell-glass, where the female was
plainly to be seen, the light falling full upon her prison. Not a
glance, not an inquiry. They all flew to the further end of the room,
into the dark corner where I had placed the tray and the empty
dish-cover.
They alighted on the wire dome, explored it persistently, beating their
wings and jostling one another. All the afternoon, until sunset, the
moths danced about the empty cage the same saraband that the actual
presence of the female had previously evoked. Finally they departed: not
all, for there were some that would not go, held by some magical
attractive force.
Truly a strange result! The moths collected where there was apparently
nothing to attract them, and remained there, unpersuaded by the sense of
sight; they passed the bell-glass actually containing the female without
halting for a moment, although she must have been seen by many of the
moths both going and coming. Maddened by a lure, they paid no attention
to the reality.
What was the lure that so deceived them? All the preceding night and all
the morning the female had remained under the wire-gauze cover;
sometimes clinging to the wire-work, sometimes resting on the sand in
the tray. Whatever she touched--above all, apparently, with her
distended abdomen--was impregnated, as a result of long contact, with a
certain emanation. This was her lure, her love-philtre; this it was that
revolutionised the Oak Eggar world. The sand retained it for some time
and diffused the effluvium in turn.
They passed by the glass prison in which the female was then confined
and hastened to the meshes of wire and the sand on which the magic
philtre had been poured; they crowded round the deserted chamber where
nothing of the magician remained but the odorous testimony of her
sojourn.
The irresistible philtre requires time for its elaboration. I conceive
of it as an exhalation which is given off during courtship and gradually
saturates whatever is in contact with the motionless body of the female.
If the bell-glass was placed directly on the table, or, still better, on
a square of glass, the communication between the inside and the outside
was insufficient, and the males, perceiving no odour, did not arrive so
long as that condition of things obtained. It was plain that this
failure of transmission was not due to the action of the glass as a
screen simply, for if I established a free communication between the
interior of the bell-glass and the open air by supporting it on three
small blocks, the moths did not collect round it at once, although there
were plenty in the room; but in the course of half an hour or so the
feminine alembic began to operate, and the visitors crowded round the
bell-glass as usual.
In possession of these data and this unexpected enlightenment I varied
the experiments, but all pointed to the same conclusion. In the morning
I established the female under the usual wire-gauze cover. For support I
gave her a little twig of oak as before. There, motionless as if dead,
she crouched for hours, half buried in the dry leaves, which would thus
become impregnated with her emanations.
When the hour of the daily visits drew near I removed the twig, which
was by then thoroughly saturated with the emanations, and laid it on a
chair not far from the open window. On the other hand I left the female
under the cover, plainly exposed on the table in the middle of the room.
The moths arrived as usual: first one, then two, then three, and
presently five and six. They entered, flew out again, re-entered,
mounted, descended, came and went, always in the neighbourhood of the
window, not far from which was the chair on which the twig lay. None
made for the large table, on which, a few steps further from the window,
the female awaited them in the wire-gauze cover. They hesitated, that
was plain; they were still seeking.
Finally they found. And what did they find? Simply the twig, which that
morning had served the ample matron as bed. Their wings rapidly
fluttering, they alighted on the foliage; they explored it over and
under, probed it, raised it, and displaced it so that the twig finally
fell to the floor. None the less they continued to probe between the
leaves. Under the buffets and the draught of their wings and the
clutches of their eager feet the little bundle of leaves ran along the
floor like a scrap of paper patted by the paws of a cat.
While the twig was sliding away with its band of investigators two new
arrivals appeared. The chair lay in their path. They stopped at it and
searched eagerly at the very spot on which the twig had been lying. But
with these, as with the others, the real object of their desires was
there, close by, under a wire cover which was not even veiled. None took
any note of it. On the floor, a handful of butterflies were still
hustling the bunch of leaves on which the female had reposed that
morning; others, on the chair, were still examining the spot where the
twig had lain. The sun sank, and the hour of departure struck. Moreover,
the emanations were growing feebler, were evaporating. Without more ado
the visitors left. We bade them goodbye till the morrow.
The following tests showed me that the leaf-covered twig which
accidentally enlightened me might be replaced by any other substance.
Some time before the visitors were expected I placed the female on a bed
of cloth or flannel, card or paper. I even subjected her to the rigours
of a camp-bed of wood, glass, marble, and metal. All these objects,
after a contact of sufficient duration, had the same attraction for the
males as the female moth herself. They retained this property for a
longer or shorter time, according to their nature. Cardboard, flannel,
dust, sand, and porous objects retained it longest. Metals, marble, and
glass, on the contrary, quickly lost their efficacy. Finally, anything
on which the female had rested communicated its virtues by contact;
witness the butterflies crowding on the straw-bottomed chair after the
twig fell to the ground.
Using one of the most favourable materials--flannel, for example--I
witnessed a curious sight. I placed a morsel of flannel on which the
mother moth had been lying all the morning at the bottom of a long
test-tube or narrow-necked bottle, just permitting of the passage of a
male moth. The visitors entered the vessels, struggled, and did not know
how to extricate themselves. I had devised a trap by means of which I
could exterminate the tribe. Delivering the prisoners, and removing the
flannel, which I placed in a perfectly closed box, I found that they
re-entered the trap; attracted by the effluvia that the flannel had
communicated to the glass.
I was now convinced. To call the moths of the countryside to the
wedding-feast, to warn them at a distance and to guide them the nubile
female emits an odour of extreme subtlety, imperceptible to our own
olfactory sense-organs. Even with their noses touching the moth, none of
my household has been able to perceive the faintest odour; not even the
youngest, whose sensibility is as yet unvitiated.
This scent readily impregnates any object on which the female rests for
any length of time, when this object becomes a centre of attraction as
active as the moth herself until the effluvium is evaporated.
Nothing visible betrays the lure. On a sheet of paper, a recent
resting-place, around which the visitors had crowded, there was no
visible trace, no moisture; the surface was as clean as before the
impregnation.
The product is elaborated slowly, and must accumulate a little before it
reveals its full power. Taken from her couch and placed elsewhere the
female loses her attractiveness for the moment and is an object of
indifference; it is to the resting-place, saturated by long contact,
that the arrivals fly. But the female soon regains her power.
The emission of the warning effluvium is more or less delayed according
to the species. The recently metamorphosed female must mature a little
and her organs must settle to their work. Born in the morning, the
female of the Great Peacock moth sometimes has visitors the night of the
same day; but more often on the second day, after a preparation of forty
hours or so. The Oak Eggar does not publish her banns of marriage before
the third or fourth day.
Let us return for a moment to the problematical function of the antennæ.
The male Oak Eggar has a sumptuous pair, as has the Great Peacock or
Emperor Moth. Are we to regard these silky "feelers" as a kind of
directing compass?--I resumed, but without attaching much importance to
the matter, my previous experiment of amputation. None of those operated
on returned. Do not let us draw conclusions from that fact alone. We saw
in the case of the Great Peacock that more serious reasons than the
truncation of the antennæ made return as a rule impossible.
Moreover, a second Bombyx or Eggar, the Clover Moth, very like the Oak
Eggar, and like it superbly plumed, poses us a very difficult problem.
It is fairly abundant around my home; even in the orchard I find its
cocoon, which is easily confounded with that of the Oak Eggar. I was at
first deceived by the resemblance. From six cocoons, which I expected to
yield Oak Eggars, I obtained, about the end of August, six females of
the other species. Well: about these six females, born in my house,
never a male appeared, although they were undoubtedly present in the
neighbourhood.
If the ample and feathery antennæ are truly sense-organs, which receive
information of distant objects, why were not my richly plumed neighbours
aware of what was passing in my study? Why did their feathery "feelers"
leave them in ignorance of events which would have brought flocks of the
other Eggar? Once more, the organ does not determine the aptitude. One
individual or species is gifted, but another is not, despite an organic
equality.
CHAPTER XVI
A TRUFFLE-HUNTER: THE _BOLBOCERAS GALLICUS_
In the matter of physics we hear of nothing to-day but the Röntgen rays,
which penetrate opaque bodies and photograph the invisible. A splendid
discovery; but nothing very remarkable as compared with the surprises
reserved for us by the future, when, better instructed as to the why and
wherefore of things than now, and supplementing our feeble senses by
means of science, we shall succeed in rivalling, however imperfectly,
the sensorial acuteness of the lower animals.
How enviable, in how many cases, is the superiority of the beasts! It
makes us realise the insufficiency of our impressions, and the very
indifferent efficacy of our sense-organs; it proclaims realities which
amaze us, so far are they beyond our own attributes.
A miserable caterpillar, the Processional caterpillar, found on the
pine-tree, has its back covered with meteorological spiracles which
sense the coming weather and foretell the storm; the bird of prey, that
incomparable watchman, sees the fallen mule from the heights of the
clouds; the blind bats guided their flight without collision through the
inextricable labyrinth of threads devised by Spallanzani; the carrier
pigeon, at a hundred leagues from home, infallibly regains its loft
across immensities which it has never known; and within the limits of
its more modest powers a bee, the Chalicodoma, also adventures into the
unknown, accomplishing its long journey and returning to its group of
cells.
Those who have never seen a dog seeking truffles have missed one of the
finest achievements of the olfactory sense. Absorbed in his duties, the
animal goes forward, scenting the wind, at a moderate pace. He stops,
questions the soil with his nostrils, and, without excitement, scratches
the earth a few times with one paw. "There it is, master!" his eyes seem
to say: "there it is! On the faith of a dog, there are truffles here!"
He says truly. The master digs at the point indicated. If the spade goes
astray the dog corrects the digger, sniffing at the bottom of the hole.
Have no fear that stones and roots will confuse him; in spite of depth
and obstacles, the truffle will be found. A dog's nose cannot lie.
I have referred to the dog's speciality as a subtle sense of smell. That
is certainly what I mean, if you will understand by that that the nasal
passages of the animal are the seat of the perceptive organ; but is the
thing perceived always a simple smell in the vulgar acceptation of the
term--an effluvium such as our own senses perceive? I have certain
reasons for doubting this, which I will proceed to relate.
On various occasions I have had the good fortune to accompany a
truffle-dog of first-class capacities on his rounds. Certainly there was
not much outside show about him, this artist that I so desired to see at
work; a dog of doubtful breed, placid and meditative; uncouth,
ungroomed, and quite inadmissible to the intimacies of the hearthrug.
Talent and poverty are often mated.
His master, a celebrated _rabassier_[5] of the village, being convinced
that my object was not to steal his professional secrets, and so sooner
or later to set up in business as a competitor, admitted me of his
company, a favour of which he was not prodigal. From the moment of his
regarding me not as an apprentice, but merely as a curious spectator,
who drew and wrote about subterranean vegetable affairs, but had no wish
to carry to market my bagful of these glories of the Christmas goose,
the excellent man lent himself generously to my designs.
It was agreed between us that the dog should act according to his own
instincts, receiving the customary reward, after each discovery, no
matter what its size, of a crust of bread the size of a finger-nail.
Every spot scratched by his paw should be excavated, and the object
indicated was to be extracted without reference to its marketable value.
In no case was the experience of the master to intervene in order to
divert the dog from a spot where the general aspect of things indicated
that no commercial results need be expected, for I was more concerned
with the miserable specimens unfit for the market than with the choice
specimens, though of course the latter were welcomed.
Thus conducted, this subterranean botanising was extremely fruitful.
With that perspicacious nose of his the dog obtained for me both large
and small, fresh and putrid, odorous and inodorous, fragrant and
offensive. I was amazed at my collection, which comprised the greater
number of the hypogenous fungi of the neighbourhood.
What a variety of structure, and above all of odour, the primordial
quality in this question of scent! There were some that had no
appreciable scent beyond a vague fungoid flavour, more or less common to
all. Others smelt of turnips, of sour cabbage; some were fetid,
sufficiently so to make the house of the collector noisome. Only the
true truffle possessed the aroma dear to epicures. If odour, as we
understand it, is the dog's only guide, how does he manage to follow
that guide amidst all these totally different odours? Is he warned of
the contents of the subsoil by a general emanation, by that fungoid
effluvium common to all the species? Thus a somewhat embarrassing
question arises.
I paid special attention to the ordinary toadstools and mushrooms, which
announced their near advent by cracking the surface of the soil. Now
these points, where my eyes divined the cryptogam pushing back the soil
with its button-like heads, these points, where the ordinary fungoid
odour was certainly very pronounced, were never selected by the dog. He
passed them disdainfully, without a sniff, without a stroke of the paw.
Yet the fungi were underground, and their odour was similar to that I
have already referred to.
I came back from my outings with the conviction that the truffle-finding
nose has some better guide than odour such as we with our sense-organs
conceive it. It must perceive effluvia of another order as well;
entirely mysterious to us, and therefore not utilised. Light has its
dark rays--rays without effect upon our retinas, but not apparently on
all. Why should not the domain of smell have its secret emanations,
unknown to our senses and perceptible to a different sense-organ?
If the scent of the dog leaves us perplexed in the sense that we cannot
possibly say precisely, cannot even suspect what it is that the dog
perceives, at least it is clear that it would be erroneous to refer
everything to human standards. The world of sensations is far larger
than the limits of our own sensibility. What numbers of facts relating
to the interplay of natural forces must escape us for want of
sufficiently sensitive organs!
The unknown--that inexhaustible field in which the men of the future
will try their strength--has harvests in store for us beside which our
present knowledge would show as no more than a wretched gleaning. Under
the sickle of science will one day fall the sheaves whose grain would
appear to-day as senseless paradoxes. Scientific dreams? No, if you
please, but undeniable positive realities, affirmed by the brute
creation, which in certain respects has so great an advantage over us.
Despite his long practice of his calling, despite the scent of the
object he was seeking, the _rabassier_ could not divine the presence of
the truffle, which ripens in winter under the soil, at a depth of a foot
or two; he must have the help of a dog or a pig, whose scent is able to
discover the secrets of the soil. These secrets are known to various
insects even better than to our two auxiliaries. They have in
exceptional perfection the power of discovering the tubers on which
their larvæ are nourished.
From truffles dug up in a spoiled condition, peopled with vermin, and
placed in that condition, with a bed of fresh sand, in a glass jar, I
have in the past obtained a small red beetle, known as the
truffle-beetle (_Anisotoma cinnamomea_, Panz.), and various Diptera,
among which is a Sapromyzon which, by its sluggish flight and its
fragile form, recalls the _Scatophaga scybalaria_, the yellow velvety
fly which is found in human excrement in the autumn. The latter finds
its refuge on the surface of the soil, at the foot of a wall or hedge or
under a bush; but how does the former know just where the truffle lies
under the soil, or at what depth? To penetrate to that depth, or to seek
in the subsoil, is impossible. Its fragile limbs, barely able to move a
grain of sand, its extended wings, which would bar all progress in a
narrow passage, and its costume of bristling silken pile, which would
prevent it from slipping through crevices, all make such a task
impossible. The Sapromyzon is forced to lay its eggs on the surface of
the soil, but it does so on the precise spot which overlies the truffle,
for the grubs would perish if they had to wander at random in search of
their provender, the truffle being always thinly sown.
The truffle fly is informed by the sense of smell of the points
favourable to its maternal plans; it has the talents of the truffle-dog,
and doubtless in a higher degree, for it knows naturally, without having
been taught, what its rival only acquires through an artificial
education.
It would be not uninteresting to follow the Sapromyzon in its search in
the open woods. Such a feat did not strike me as particularly possible;
the insect is rare, flies off quickly when alarmed, and is lost to
view. To observe it closely under such conditions would mean a loss of
time and an assiduity of which I do not feel capable. Another
truffle-hunter will show us what we could hardly learn from the fly.
This is a pretty little black beetle, with a pale, velvety abdomen; a
spherical insect, as large as a biggish cherry-stone. Its official title
is _Bolboceras gallicus_, Muls. By rubbing the end of the abdomen
against the edge of the wing-cases it produces a gentle chirping sound
like the cheeping of nestlings when the mother-bird returns to the nest
with food. The male wears a graceful horn on his head; a duplicate, in
little, of that of the _Copris hispanus_.
Deceived by this horn, I at first took the insect for a member of the
corporation of dung-beetles, and as such I reared it in captivity. I
offered it the kind of diet most appreciated by its supposed relatives,
but never, never would it touch such food. For whom did I take it? Fie
upon me! To offer ordure to an epicure! It required, if not precisely
the truffle known to our _chefs_ and _gourmets_, at least its
equivalent.
This characteristic I grasped only after patient investigation. At the
southern foot of the hills of Sérignan, not far from the village, is a
wood of maritime pines alternating with rows of cypress. There, towards
Toussaint, after the autumnal rains, you may find an abundance of the
mushrooms or "toadstools" that affect the conifers; especially the
delicious Lactaris, which turns green if the points are rubbed and drips
blood if broken. In the warm days of autumn this is the favourite
promenade of the members of my household, being distant enough to
exercise their young legs, but near enough not to fatigue them.
There one finds and sees all manner of things: old magpies' nests, great
bundles of twigs; jays, wrangling after filling their crops with the
acorns of the neighbouring oaks; rabbits, whose little white upturned
scuts go bobbing away through the rosemary bushes; dung-beetles, which
are storing food for the winter and throwing up their rubbish on the
threshold of their burrows. And then the fine sand, soft to the touch,
easily tunnelled, easily excavated or built into tiny huts which we
thatch with moss and surmount with the end of a reed for a chimney; and
the delicious meal of apples, and the sound of the æolian harps which
softly whisper among the boughs of the pines!
For the children it is a real paradise, where they can receive the
reward of well-learned lessons. The grown-ups also can share in the
enjoyment. As for myself, for long years I have watched two insects
which are found there without getting to the bottom of their domestic
secrets. One is the _Minotaurus typhæus_, whose male carries on his
corselet three spines which point forward. The old writers called him
the Phalangist, on account of his armour, which is comparable to the
three ranks of lances of the Macedonian phalanx.
This is a robust creature, heedless of the winter. All during the cold
season, whenever the weather relents a little, it issues discreetly from
its lodging, at nightfall, and gathers, in the immediate neighbourhood
of its dwelling, a few fragments of sheep-dung and ancient olives which
the summer suns have dried. It stacks them in a row at the end of its
burrow, closes the door, and consumes them. When the food is broken up
and exhausted of its meagre juices it returns to the surface and renews
its store. Thus the winter passes, famine being unknown unless the
weather is exceptionally hard.
The second insect which I have observed for so long among the pines is
the Bolboceras. Its burrows, scattered here and there, higgledy-piggledy
with those of the Minotaur, are easy to recognise. The burrow of the
Phalangist is surmounted by a voluminous rubbish-dump, the materials of
which are piled in the form of a cylinder as long as the finger. Each of
these dumps is a load of refuse and rubbish pushed outward by the little
sapper, which shoulders it up from below. The orifice is closed whenever
the insect is at home, enlarging its tunnel or peacefully enjoying the
contents of its larder.
The lodging of the Bolboceras is open and surrounded simply by a mound
of sand. Its depth is not great; a foot or hardly more. It descends
vertically in an easily shifted soil. It is therefore easy to inspect
it, if we take care first of all to dig a trench so that the wall of the
burrow may be afterwards cut away, slice by slice, with the blade of a
knife. The burrow is thus laid bare along its whole extent, from the
surface to the bottom, until nothing remains of it but a
demi-cylindrical groove.
Often the violated dwelling is empty. The insect has departed in the
night, having finished its business there. It is a nomad, a
night-walker, which leaves its dwelling without regret and easily
acquires another. Often, on the other hand, the insect will be found at
the bottom of the burrow; sometimes a male, sometimes a female, but
always alone. The two sexes, equally zealous in excavating their
burrows, work apart without collaboration. This is no family mansion for
the rearing of offspring; it is a temporary dwelling, made by each
insect for its own benefit.
Sometimes the burrow contains nothing but the well-sinker surprised at
its work: sometimes--and not rarely--the hermit will be found embracing
a small subterranean fungus, entire or partly consumed. It presses it
convulsively to its bosom and will not be parted from it. This is the
insect's booty: its worldly wealth. Scattered crumbs inform us that we
have surprised the beetle at a feast.
Let us deprive the insect of its booty. We find a sort of irregular,
rugged, purse-like object, varying in size from the largeness of a pea
to that of a cherry. The exterior is reddish, covered with fine warts,
having an appearance not unlike shagreen; the interior, which has no
communication with the exterior, is smooth and white. The pores, ovoidal
and diaphanous, are contained, in groups of eight, in long capsules.
From these characteristics we recognise an underground cryptogam, known
to the botanists as _Hydnocystis arenaria_, and a relation of the
truffle.
This discovery begins to throw a light on the habits of the Bolboceras
and the cause of its burrows, so frequently renewed. In the calm of the
twilight the little truffle-hunter goes abroad, chirping softly to
encourage itself. It explores the soil, and interrogates it as to its
contents, exactly as does the truffle-gatherer's dog. The sense of smell
warns it that the desired object is beneath it, covered by a few inches
of sand. Certain of the precise point where the treasure lies, it sinks
a well vertically downwards, and infallibly reaches it. So long as there
is food left it does not again leave the burrow. It feasts happily at
the bottom of its well, heedless of the open or imperfectly closed
burrow.
When no more food is left it removes in search of further booty, which
becomes the occasion of another burrow, this too in its turn to be
abandoned. So many truffles eaten necessitate so many burrows, which are
mere dining-rooms or pilgrim's larders. Thus pass the autumn and the
spring, the seasons of the _Hydnocystis_, in the pleasures of the table
and removal from one house to another.
To study the insect _rabassier_ in my own house I had to obtain a small
store of its favourite food. To seek it myself, by digging at random,
would have resulted merely in waste of time; the little cryptogam is not
so common that I could hope to find it without a guide. The
truffle-hunter must have his dog; my guide should be the Bolboceras
itself. Behold me, then, a _rabassier_ of a kind hitherto unknown. I
have told my secret, although I fear my original teacher will laugh at
me if he ever hears of my singular form of competition.
The subterranean fungi grow only at certain points, but they are often
found in groups. Now, the beetle has passed this way; with its subtle
sense of smell it has recognised the ground as favourable; for its
burrows are numerous. Let us dig, then, in the neighbourhood of these
holes. The sign is reliable; in a few hours, thanks to the signs of the
Bolboceras, I obtain a handful of specimens of the _Hydnocystis_. It is
the first time I have ever found this fungus in the ground. Let us now
capture the insect--an easy matter, for we have only to excavate the
burrows.
The same evening I begin my experiments. A wide earthen pan is filled
with fresh sand which has been passed through a sieve. With the aid of a
stick the thickness of a finger I make six vertical holes in the sand:
they are conveniently far apart, and are eight inches in depth. A
_Hydnocystis_ is placed at the bottom of each; a fine straw is then
inserted, to show me the precise position later. Finally the six holes
are filled with sand which is beaten down so that all is firm. When the
surface is perfectly level, and everywhere the same, except for the six
straws, which mean nothing to the insect, I release my beetles, covering
them with a wire-gauze cover. They are eight in number.
At first I see nothing but the inevitable fatigue due to the incidents
of exhumation, transport, and confinement in a strange place. My exiles
try to escape: they climb the wire walls, and finally all take to earth
at the edge of their enclosure. Night comes, and all is quiet. Two hours
later I pay my prisoners a last visit. Three are still buried under a
thin layer of sand. The other five have sunk each a vertical well at the
very foot of the straws which indicate the position of the buried fungi.
Next morning the sixth straw has its burrow like the rest.
It is time to see what is happening underground. The sand is
methodically removed in vertical slices. At the bottom of each burrow is
a Bolboceras engaged in eating its truffle.
Let us repeat the experiment with the partly eaten fungi. The result is
the same. In one short night the food is divined under its covering of
sand and attained by means of a burrow which descends as straight as a
plumb-line to the point where the fungus lies. There has been no
hesitation, no trial excavations which have nearly discovered the object
of search. This is proved by the surface of the soil, which is
everywhere just as I left it when smoothing it down. The insect could
not make more directly for the objective if guided by the sense of
sight; it digs always at the foot of the straw, my private sign. The
truffle-dog, sniffing the ground in search of truffles, hardly attains
this degree of precision.
Does the _Hydnocystis_ possess a very keen odour, such as we should
expect to give an unmistakable warning to the senses of the consumer? By
no means. To our own sense of smell it is a neutral sort of object, with
no appreciable scent whatever. A little pebble taken from the soil would
affect our senses quite as strongly with its vague savour of fresh
earth. As a finder of underground fungi the Bolboceras is the rival of
the dog. It would be the superior of the dog if it could generalise; it
is, however, a rigid specialist, recognising nothing but the
_Hydnocystis_. No other fungus, to my knowledge, either attracts it or
induces it to dig.[6]
Both dog and beetle are very near the subsoil which they scrutinise; the
object they seek is at no great depth. At a greater depth neither dog
nor insect could perceive such subtle effluvia, nor even the odour of
the truffle. To attract insect or animal at a great distance powerful
odours are necessary, such as our grosser senses can perceive. Then the
exploiters of the odorous substance hasten from afar off and from all
directions.
If for purposes of study I require specimens of such insects as dissect
dead bodies I expose a dead mole to the sunlight in a distant corner of
my orchard. As soon as the creature is swollen with the gases of
putrefaction, and the fur commences to fall from the greenish skin, a
host of insects arrive--Silphidæ, Dermestes, Horn-beetles, and
Necrophori--of which not a single specimen could ever be obtained in my
garden or even in the neighbourhood without the use of such a bait.
They have been warned by the sense of smell, although far away in all
directions, while I myself can escape from the stench by recoiling a few
paces. In comparison with their sense of smell mine is miserable; but in
this case, both for me and for them, there is really what our language
calls an odour.
I can do still better with the flower of the Serpent Arum (_Arum
dracunculus_), so noteworthy both for its form and its incomparable
stench. Imagine a wide lanceolated blade of a vinous purple, some twenty
inches in length, which is twisted at the base into an ovoid purse about
the size of a hen's egg. Through the opening of this capsule rises the
central column, a long club of a livid green, surrounded at the base by
two rings, one of ovaries and the other of stamens. Such, briefly, is
the flower or rather the inflorescence of the Serpent Arum.
For two days it exhales a horrible stench of putrid flesh; a dead dog
could not produce such a terrible odour. Set free by the sun and the
wind, it is odious, intolerable. Let us brave the infected atmosphere
and approach; we shall witness a curious spectacle.
Warned by the stench, which travels far and wide, a host of insects are
flying hither; such insects as dissect the corpses of frogs, adders,
lizards, hedgehogs, moles and field-mice--creatures that the peasant
finds beneath his spade and throws disembowelled on the path. They fall
upon the great leaf, whose livid purple gives it the appearance of a
strip of putrid flesh; they dance with impatience, intoxicated by the
corpse-like odour which to them is so delicious; they roll down its
steep face and are engulfed in the capsule. After a few hours of hot
sunlight the receptacle is full.
Let us look into the capsule through the narrow opening. Nowhere else
could you see such a mob of insects. It is a delirious mixture of backs
and bellies, wing-covers and legs, which swarms and rolls upon itself,
rising and falling, seething and boiling, shaken by continual
convulsions, clicking and squeaking with a sound of entangled
articulations. It is a bacchanal, a general access of delirium tremens.
A few, but only a few, emerge from the mass. By the central mast or the
walls of the purse they climb to the opening. Do they wish to take
flight and escape? By no means. On the threshold of the cavity, while
already almost at liberty, they allow themselves to fall into the
whirlpool, retaken by their madness. The lure is irresistible. None will
break free from the swarm until the evening, or perhaps the next day,
when the heady fumes will have evaporated. Then the units of the swarm
disengage themselves from their mutual embraces, and slowly, as though
regretfully, take flight and depart. At the bottom of this devil's purse
remains a heap of the dead and dying, of severed limbs and wing-covers
torn off; the inevitable sequels of the frantic orgy. Soon the woodlice,
earwigs, and ants will appear to prey upon the injured.
What are these insects doing? Were they the prisoners of the flower,
converted into a trap which allowed them to enter but prevented their
escape by means of a palisade of converging hairs? No, they were not
prisoners; they had full liberty to escape, as is proved by the final
exodus, which is in no way impeded. Deceived by a fallacious odour, were
they endeavouring to lay and establish their eggs as they would have
done under the shelter of a corpse? No; there is no trace of eggs in the
purse of the Arum. They came convoked by the odour of a decaying body,
their supreme delight; an intoxication seized them, and they rushed into
the eddying swarm to take part in a festival of carrion-eaters.
I was anxious to count the number of those attracted. At the height of
the bacchanal I emptied the purse into a bottle. Intoxicated as they
were, many would escape my census, and I wished to ensure its accuracy.
A few drops of carbon bisulphide quieted the swarm. The census proved
that there were more than four hundred insects in the purse of the Arum.
The collection consisted entirely of two species--Dermestes and
Saprinidæ--both eager prospectors of carrion and animal detritus during
the spring.
My friend Bull, an honest dog all his lifetime if ever there was one,
amongst other eccentricities had the following: finding in the dust of
the road the shrivelled body of a mole, flattened by the feet of
pedestrians, mummified by the heat of the sun, he would slide himself
over it, from the tip of his nose to the root of his tail, he would rub
himself against it deliciously over and over again, shaken with nervous
spasms, and roll upon it first in one direction, then in the other.
It was his sachet of musk, his flask of eau-de-Cologne. Perfumed to his
liking, he would rise, shake himself, and proceed on his way, delighted
with his toilet. Do not let us scold him, and above all do not let us
discuss the matter. There are all kinds of tastes in a world.
Why should there not be insects with similar habits among the amateurs
of corpse-like savours? We see Dermestes and Saprinidæ hastening to the
arum-flower. All day long they writhe and wriggle in a swarm, although
perfectly free to escape; numbers perish in the tumultuous orgy. They
are not retained by the desire of food, for the arum provides them with
nothing eatable; they do not come to breed, for they take care not to
establish their grubs in that place of famine. What are these frenzied
creatures doing? Apparently they are intoxicated with fetidity, as was
Bull when he rolled on the putrid body of a mole.
This intoxication draws them from all parts of the neighbourhood,
perhaps over considerable distances; how far we do not know. The
Necrophori, in quest of a place where to establish their family, travel
great distances to find the corpses of small animals, informed by such
odours as offend our own senses at a considerable distance.
The _Hydnocystis_, the food of the Bolboceras, emits no such brutal
emanations as these, which readily diffuse themselves through space; it
is inodorous, at least to our senses. The insect which seeks it does not
come from a distance; it inhabits the places wherein the cryptogam is
found. Faint as are the effluvia of this subterranean fungus, the
prospecting epicure, being specially equipped, perceives them with the
greatest ease; but then he operates at close range, from the surface of
the soil. The truffle-dog is in the same case; he searches with his nose
to the ground. The true truffle, however, the essential object of his
search, possesses a fairly vivid odour.
But what are we to say of the Great Peacock moth and the Oak Eggar, both
of which find their captive female? They come from the confines of the
horizon. What do they perceive at that distance? Is it really an odour
such as we perceive and understand? I cannot bring myself to believe it.
The dog finds the truffle by smelling the earth quite close to the
tuber; but he finds his master at great distances by following his
footsteps, which he recognises by their scent. Yet can he find the
truffle at a hundred yards? or his master, in the complete absence of a
trail? No. With all his fineness of scent, the dog is incapable of such
feats as are realised by the moth, which is embarrassed neither by
distance nor the absence of a trail.
It is admitted that odour, such as affects our olfactory sense, consists
of molecules emanating from the body whose odour is perceived. The
odorous material becomes diffused through the air to which it
communicates its agreeable or disagreeable aroma. Odour and taste are to
a certain extent the same; in both there is contact between the material
particles causing the impression and the sensitive papillæ affected by
the impression.
That the Serpent Arum should elaborate a powerful essence which
impregnates the atmosphere and makes it noisome is perfectly simple and
comprehensible. Thus the Dermestes and Saprinidæ, those lovers of
corpse-like odours, are warned by molecular diffusion. In the same way
the putrid frog emits and disseminates around it atoms of putrescence
which travel to a considerable distance and so attract and delight the
Necrophorus, the carrion-beetle.
But in the case of the Great Peacock or the Oak Eggar, what molecules
are actually disengaged? None, according to our sense of smell. And yet
this lure, to which the males hasten so speedily, must saturate with its
molecules an enormous hemisphere of air--a hemisphere some miles in
diameter! What the atrocious fetor of the Arum cannot do the absence of
odour accomplishes! However divisible matter may be, the mind refuses
such conclusions. It would be to redden a lake with a grain of carmine;
to fill space with a mere nothing.
Moreover, where my laboratory was previously saturated with powerful
odours which should have overcome and annihilated any particularly
delicate effluvium, the male moths arrived without the least indication
of confusion or delay.
A loud noise stifles a feeble note and prevents it from being heard; a
brilliant light eclipses a feeble glimmer. Heavy waves overcome and
obliterate ripples. In the two cases cited we have waves of the same
nature. But a clap of thunder does not diminish the feeblest jet of
light; the dazzling glory of the sun will not muffle the slightest
sound. Of different natures, light and sound do not mutually interact.
My experiment with spike-lavender, naphthaline, and other odours seems
to prove that odour proceeds from two sources. For emission substitute
undulation, and the problem of the Great Peacock moth is explained.
Without any material emanation a luminous point shakes the ether with
its vibrations and fills with light a sphere of indefinite magnitude.
So, or in some such manner, must the warning effluvium of the mother Oak
Eggar operate. The moth does not emit molecules; but something about it
vibrates, causing waves capable of propagation to distances incompatible
with an actual diffusion of matter.
From this point of view, smell would have two domains--that of particles
dissolved in the air and that of etheric waves.[7] The former domain
alone is known to us. It is also known to the insect. It is this that
warns the Saprinidæ of the fetid arum, the Silphidæ and the Necrophori
of the putrid mole.
The second category of odour, far superior in its action through space,
escapes us completely, because we lack the essential sensory equipment.
The Great Peacock moth and the Oak Eggar know it at the time of their
nuptial festivities. Many others must share it in differing degrees,
according to the exigencies of their way of life.
Like light, odour has its X-rays. Let science, instructed by the insect,
one day give us a radiograph sensitive to odours, and this artificial
nose will open a new world of marvels.
CHAPTER XVII
THE ELEPHANT-BEETLE
Some of our machines have extraordinary-looking mechanisms, which remain
inexplicable so long as they are seen in repose. But wait until the
whole is in motion; then the uncouth-looking contrivance, with its
cog-wheels interacting and its connecting-rods oscillating, will reveal
the ingenious combination in which all things are skilfully disposed to
produce the desired effects. It is the same with certain insects; with
certain weevils, for instance, and notably with the Acorn-beetles or
Balanini, which are adapted, as their name denotes, to the exploitation
of acorns, nuts, and other similar fruits.
The most remarkable, in my part of France, is the Acorn Elephant
(_Balaninus elephas_, Sch.). It is well named; the very name evokes a
mental picture of the insect. It is a living caricature, this beetle
with the prodigious snout. The latter is no thicker than a horsehair,
reddish in colour, almost rectilinear, and of such length that in order
not to stumble the insect is forced to carry it stiffly outstretched
like a lance in rest. What is the use of this embarrassing pike, this
ridiculous snout?
Here I can see some reader shrug his shoulders. Well, if the only end of
life is to make money by hook or by crook, such questions are certainly
ridiculous.
Happily there are some to whom nothing in the majestic riddle of the
universe is little. They know of what humble materials the bread of
thought is kneaded; a nutriment no less necessary than the bread made
from wheat; and they know that both labourers and inquirers nourish the
world with an accumulation of crumbs.
Let us take pity on the question, and proceed. Without seeing it at
work, we already suspect that the fantastic beak of the Balaninus is a
drill analogous to those which we ourselves use in order to perforate
hard materials. Two diamond-points, the mandibles, form the terminal
armature of the drill. Like the Larinidæ, but under conditions of
greater difficulty, the Curculionidæ must use the implement in order to
prepare the way for the installation of their eggs.
But however well founded our suspicion may be, it is not a certitude. I
can only discover the secret by watching the insect at work.
Chance, the servant of those that patiently solicit it, grants me a
sight of the acorn-beetle at work, in the earlier half of October. My
surprise is great, for at this late season all industrial activity is as
a rule at an end. The first touch of cold and the entomological season
is over.
To-day, moreover, it is wild weather; the _bise_ is moaning, glacial,
cracking one's lips. One needs a robust faith to go out on such a day in
order to inspect the thickets. Yet if the beetle with the long beak
exploits the acorns, as I think it does, the time presses if I am to
catch it at its work. The acorns, still green, have acquired their full
growth. In two or three weeks they will attain the chestnut brown of
perfect maturity, quickly followed by their fall.
My seemingly futile pilgrimage ends in success. On the evergreen oaks I
surprise a Balaninus with the trunk half sunk in an acorn. Careful
observation is impossible while the branches are shaken by the
_mistral_. I detach the twig and lay it gently upon the ground. The
insect takes no notice of its removal; it continues its work. I crouch
beside it, sheltered from the storm behind a mass of underwood, and
watch operations.
Shod with adhesive sandals which later on, in my laboratory, will allow
it rapidly to climb a vertical sheet of glass, the elephant-beetle is
solidly established on the smooth, steep curvature of the acorn. It is
working its drill. Slowly and awkwardly it moves around its implanted
weapon, describing a semicircle whose centre is the point of the drill,
and then another semicircle in the reverse direction. This is repeated
over and over again; the movement, in short, is identical with that we
give to a bradawl when boring a hole in a plank.
Little by little the rostrum sinks into the acorn. At the end of an hour
it has entirely disappeared. A short period of repose follows, and
finally the instrument is withdrawn. What is going to happen next?
Nothing on this occasion. The Balaninus abandons its work and solemnly
retires, disappearing among the withered leaves. For the day there is
nothing more to be learned.
But my interest is now awakened. On calm days, more favourable to the
entomologist, I return to the woods, and I soon have sufficient insects
to people my laboratory cages. Foreseeing a serious difficulty in the
slowness with which the beetle labours, I prefer to study them indoors,
with the unlimited leisure only to be found in one's own home.
The precaution is fortunate. If I had tried to continue as I began, and
to observe the Balaninus in the liberty of the woods, I should never,
even with the greatest good fortune, have had the patience to follow to
the end the choice of the acorn, the boring of the hole, and the laying
of the eggs, so meticulously deliberate is the insect in all its
affairs; as the reader will soon be able to judge.
Three species of oak-tree compose the copse inhabited by the Balaninus:
the evergreen oak and the pubescent oak, which would become fine trees
if the woodman would give them time, and the kermes oak, a mere scrubby
bush. The first species, which is the most abundant of the three, is
that preferred by the Balaninus. The acorn is firm, elongated, and of
moderate size; the cup is covered with little warts. The acorns of the
pubescent oak are usually stunted, short, wrinkled, and fluted, and
subject to premature fall. The aridity of the hills of Sérignan is
unfavourable to them. The Acorn-beetles accept them only in default of
something better.
The kermes, a dwarf oak, a ridiculous tree which a man can jump over,
surprises me by the wealth of its acorns, which are large, ovoidal
growths, the cup being covered with scales. The Balaninus could not make
a better choice; the acorn affords a safe, strong dwelling and a
capacious storehouse of food.
A few twigs from these three trees, well provided with acorns, are
arranged under the domes of some of my wire-gauze covers, the ends being
plunged into a glass of water which will keep them fresh. A suitable
number of couples are then introduced into the cages; and the latter are
placed at the windows of my study, where they obtain the direct sunlight
for the greater part of the day. Let us now arm ourselves with patience,
and keep a constant watch upon events. We shall be rewarded; the
exploitation of the acorn deserves to be seen.
Matters do not drag on for very long. Two days after these preparations
I arrive at the precise moment when the task is commenced. The mother,
larger than the male, and equipped with a longer drill, is inspecting
her acorn, doubtless with a view to depositing her eggs.
She goes over it step by step, from the point to the stem, both above
and below. On the warty cup progression is easy; over the rest of the
surface it would be impossible, were not the soles of her feet shod with
adhesive pads, which enable her to retain her hold in any position.
Without the least uncertainty of footing, the insect walks with equal
facility over the top or bottom or up the sides of the slippery fruit.
The choice is made; the acorn is recognised as being of good quality.
The time has come to sink the hole. On account of its excessive length
it is not easy to manoeuvre the beak. To obtain the best mechanical
effect the instrument must be applied perpendicularly to the convex
surface of the acorn, and the embarrassing implement which is carried in
front of the insect when the latter is not at work must now be held in
such a position as to be beneath the worker.
To obtain this result the insect rears herself upon her hind legs,
supporting herself upon the tripod formed by the end of the wing-covers
and the posterior tarsi. It would be hard to imagine anything more
curious than this little carpenter, as she stands upright and brings her
nasal bradawl down towards her body.
Now the drill is held plumb against the surface, and the boring
commences. The method is that I witnessed in the wood on the day of the
storm. Very slowly the insect veers round from right to left, then from
left to right. Her drill is not a spiral gimlet which will sink itself
by a constant rotary motion; it is a bradawl, or rather a trochar, which
progresses by little bites, by alternative erosion, first in one
direction, then the other.
Before continuing, let me record an accident which is too striking to be
passed over. On various occasions I have found the insect dead in the
midst of its task. The body is in an extraordinary position, which would
be laughable if death were not always a serious thing, above all when it
comes suddenly, in the midst of labour.
The drill is implanted in the acorn just a little beyond the tip; the
work was only commenced. At the top of the drill, at right angles to it,
the Balaninus is suspended in the air, far from the supporting surface
of the acorn. It is dried, mummified, dead I know not how long. The legs
are rigid and contracted under the body. Even if they retained the
flexibility and the power of extension that were theirs in life, they
would fall far short of the surface of the acorn. What then has
happened, that this unhappy insect should be impaled like a specimen
beetle with a pin through its head?
An accident of the workshop is responsible. On account of the length of
its implement the beetle commences her work standing upright, supported
by the two hind-legs. Imagine a slip, a false step on the part of the
two adhesive feet; the unfortunate creature will immediately lose her
footing, dragged by the elasticity of the snout, which she was forced to
bend somewhat at the beginning. Torn away from her foothold, the
suspended insect vainly struggles in air; nowhere can her feet, those
safety anchors, find a hold. She starves at the end of her snout, for
lack of foothold whereby to extricate herself. Like the artisans in our
factories, the elephant-beetle is sometimes the victim of her tools. Let
us wish her good luck, and sure feet, careful not to slip, and proceed.
On this occasion all goes well, but so slowly that the descent of the
drill, even when amplified by the magnifying-glass, cannot be perceived.
The insect veers round perpetually, rests, and resumes her work. An hour
passes, two hours, wearying the observer by their sustained attention;
for I wish to witness the precise moment when the beetle withdraws her
drill, turns round, and deposits her egg in the mouth of the orifice.
This, at least, is how I foresee the event.
Two hours go by, exhausting my patience. I call the household to my aid.
Three of us take turns, keeping an uninterrupted watch upon the
persevering creature whose secret I intend at any cost to discover.
[Illustration: 1. THE GREY LOCUST.
1'. THE NERVATURES OF THE WING.
2. THE BALANINUS FALLEN A VICTIM TO THE LENGTH OF HER PROBOSCIS.]
It was well that I called in helpers to lend me their eyes and their
attention. After eight hours--eight interminable hours, when it was
nearly night, the sentinel on the watch calls me. The insect appears to
have finished. She does, in fact, very cautiously withdraw her beak, as
though fearing to slip. Once the tool is withdrawn she holds it pointing
directly in front of her.
The moment has come.... Alas, no! Once more I am cheated; my eight hours
of observation have been fruitless. The Balaninus decamps; abandons her
acorn without laying her eggs. I was certainly right to distrust the
result of observation in the open woods. Such concentration among the
oaks, exposed to the sun, wind, and rain would have been an intolerable
task.
During the whole of October, with the aid of such helpers as are needed,
I remark a number of borings, not followed by the laying of eggs. The
duration of the observer's task varies greatly. It usually amounts to a
couple of hours; sometimes it exceeds half the day.
With what object are these perforations made, so laborious and yet so
often unused? Let us first of all discover the position of the egg, and
the first mouthfuls taken by the grub, and perhaps the reply will be
found.
The peopled acorns remain on the oak, held in their cups as though
nothing had occurred to the detriment of the cotyledons. With a little
attention they may be readily recognised. Not far from the cup, on the
smooth, still green envelope of the acorn a little point is visible; a
tiny needle-prick. A narrow brown aureole, the product of mortification,
is not long in appearing. This marks the opening of the hole. Sometimes,
but more rarely, the hole is drilled through the cup itself.
Let us select those acorns which have been recently perforated: that is
to say, those in which the perforation is not yet surrounded by the
brown ring which appears in course of time. Let us shell them. Many
contain nothing out of the way; the Balaninus has bored them but has not
laid her eggs in them. They resemble the acorns which for hours and
hours were drilled in my laboratory but not utilised. Many, on the
contrary, contain an egg.
Now however distant the entrance of the bore may be, this egg is always
at the bottom of the acorn, within the cup, at the base of the
cotyledonary matter. The cup furnishes a thin film like swan-skin which
imbibes the sapid exudations from the stem, the source of nourishment. I
have seen a young grub, hatched under my eyes, eat as his first
mouthfuls this tender cottony layer, which is moist and flavoured with
tannin.
Such nutriment, juicy and easy of digestion, like all nascent organic
matter, is only found in this particular spot; and it is only there,
between the cup and the base of the cotyledons, that the elephant-beetle
establishes her egg. The insect knows to a nicety the position of the
portions best adapted to the feeble stomach of the newly hatched larva.
Above this is the tougher nutriment of the cotyledons. Refreshed by its
first meal, the grub proceeds to attack this; not directly, but in the
tunnel bored by the mother, which is littered with tiny crumbs and
half-masticated shavings. With this light mealy diet the strength of the
grub increases, and it then plunges directly into the substance of the
acorn.
These data explain the tactics of the gravid mother. What is her object
when, before proceeding to sink her hole, she inspects her acorn, from
above, below, before and behind, with such meticulous care? She is
making sure that the acorn is not already occupied. The larder is amply
stored, but it does not contain enough for two. Never in fact, have I
found two larvæ in the same acorn. One only, always only one, digests
the copious meal and converts it into a greenish dust before leaving it
and descending to the ground. Only an insignificant shell remains
uneaten. The rule is, to each grub one acorn.
Before trusting the egg to the acorn it is therefore essential to
subject it to a thorough examination, to discover whether it already has
an occupant. This possible occupant would be at the base of the acorn,
under the cover of the cup. Nothing could be more secret than this
hiding-place. Not an eye could divine the inhabitant if the surface of
the acorn did not bear the mark of a tiny perforation.
This mark, just visible, is my guide. Its presence tells me that the
acorn is inhabited, or at least that it has been prepared for the
reception of the egg; its absence tells me that the acorn has not yet
been appropriated. The elephant-beetle undoubtedly draws the same
conclusions.
I see matters from on high, with a comprehensive glance, assisted at
will by the magnifying-glass. I turn the acorn between my fingers for a
moment, and the inspection is concluded. The beetle, investigating the
acorn at close quarters, is often obliged to scrutinise practically the
entire surface before detecting the tell-tale spot. Moreover, the
welfare of her family demands a far more careful search than does my
curiosity. This is the reason for her prolonged and deliberate
examination.
The search is concluded; the acorn is recognised as unoccupied. The
drill is applied to the surface and rotated for hours; then, very often,
the insect departs, disdaining the result of her work. Why such
protracted efforts? Was the beetle piercing the fruit merely to obtain
drink and refreshment? Was the beak thrust into the depths of the base
merely to obtain, from the choicer parts, a few sips of nutritious sap?
Was the whole undertaking merely a matter of personal nourishment?
At first I believed this to be the solution, though surprised at the
display of so much perseverance rewarded by the merest sip. The
behaviour of the males, however, forced me to abandon this idea. They
also possess the long beak, and could readily make such perforations if
they wished; yet I have never seen one take up his stand upon an acorn
and work at it with his augur. Then why this fruitless labour? A mere
nothing suffices these abstemious creatures. A superficial operation
performed upon the surface of a tender leaf yields them sufficient
sustenance.
If the males, the unoccupied males who have leisure to enjoy the
pleasures of the palate, ask no more than the sap of the leaf, how
should the mothers, busied with the affairs of the breeding-season, find
time to waste upon such dearly bought pleasures as the inner juices of
the acorn? No, the acorn is not perforated for the purpose of drinking
its juices. It is possible that once the beak is deeply sunk, the female
may take a mouthful or two, but it is certain that food and drink are
not the objects in view.
At last I begin to foresee the solution of the problem. The egg, as I
have said, is always at the base of the acorn, in the midst of a soft
cottony layer which is moistened by the sap which oozes from the stalk.
The grub, upon hatching out, being as yet incapable of attacking the
firm substance of the cotyledons, masticates the delicate felt-like
layer at the base of the cup and is nourished by its juices.
But as the acorn matures this layer becomes more solid in its
consistency. The soft tissues harden; the moist tissues dry up. There is
a period during which the acorn fulfils to perfection the conditions
most conducive to the welfare of the grub. At an earlier period matters
would not have reached the desired stage; at a later period the acorn
would be too mature.
The exterior of the acorn gives no indication whatever of the progress
of this internal cookery. In order not to inflict unsuitable food on the
grub, the mother beetle, not sufficiently informed by the look of the
acorn, is thus obliged to taste, at the end of her trunk, the tissues at
the base of the cup.
The nurse, before giving her charge a spoonful of broth, tests it by
tasting it. In the same way the mother beetle plunges her trunk into the
base of the cup, to test the contents before bestowing them upon her
offspring. If the food is recognised as being satisfactory the egg is
laid; if not, the perforation is abandoned without more ado. This
explains the perforations which serve no purpose, in spite of so much
labour; the tissues at the base of the cup, being carefully tested, are
not found to be in the required condition. The elephant-beetles are
difficult to please and take infinite pains when the first mouthful of
the grub is in question. To place the egg in a position where the
new-born grub will find light and juicy and easily digested nutriment is
not enough for those far-seeing mothers; their cares look beyond this
point. An intermediary period is desirable, which will lead the little
larva from the delicacies of its first hours to the diet of hard acorn.
This intermediary period is passed in the gallery, the work of the
maternal beak. There it finds the crumbs, the shavings bitten off by the
chisels of the rostrum. Moreover, the walls of the tunnel, which are
softened by mortification, are better suited than the rest of the acorn
to the tender mandibles of the larva.
Before setting to work on the cotyledons the grub does, in fact,
commence upon the contents and walls of this tiny passage. It first
consumes the shavings lying loose in the passage; it devours the brown
fragments adhering to the walls; finally, being now sufficiently
strengthened, it attacks the body of the acorn, plunges into it, and
disappears. The stomach is ready; the rest is a blissful feast.
This intermediary tunnel must be of a certain length, in order to
satisfy the needs of infancy, so the mother must labour at the work of
drilling. If the perforation were made solely with the purpose of
tasting the material at the base of the acorn and recognising its degree
of maturity, the operation might be very much shorter, since the hole
could be sunk through the cup itself from a point close to the base.
This fact is not unrecognised; I have on occasion found the insect
perforating the scaly cup.
In such a proceeding I see the attempt of a gravid mother pressed for
time to obtain prompt information. If the acorn is suitable the boring
will be recommenced at a more distant point, through the surface of the
acorn itself. When an egg is to be laid the rule is to bore the hole
from a point as distant as is practicable from the base--as far, in
short, as the length of the rostrum will permit.
What is the object of this long perforation, which often occupies more
than half the day? Why this tenacious perseverance when, not far from
the stalk, at the cost of much less time and fatigue, the rostrum could
attain the desired point--the living spring from which the new-born grub
is to drink? The mother has her own reasons for toiling in this manner;
in doing thus she still attains the necessary point, the base of the
acorn, and at the same time--a most valuable result--she prepares for
the grub a long tube of fine, easily digested meal.
But these are trivialities! Not so, if you please, but high and
important matters, speaking to us of the infinite pains which preside
over the preservation of the least of things; witnesses of a superior
logic which regulates the smallest details.
The Balaninus, so happily inspired as a mother, has her place in the
world and is worthy of notice. So, at least, thinks the blackbird, which
gladly makes a meal of the insect with the long beak when fruits grow
rare at the end of autumn. It makes a small mouthful, but a tasty, and
is a pleasant change after such olives as yet withstand the cold.
And what without the blackbird and its rivalry of song were the
reawakening of the woods in spring? Were man to disappear, annihilated
by his own foolish errors, the festival of the life-bringing season
would be no less worthily observed, celebrated by the fluting of the
yellow-billed songster.
To the meritorious rôle of regaling the blackbird, the minstrel of the
forest, the Balaninus adds another--that of moderating the superfluity
of vegetation. Like all the mighty who are worthy of their strength, the
oak is generous; it produces acorns by the bushel. What could the earth
do with such prodigality? The forest would stifle itself for want of
room; excess would ruin the necessary.
But no sooner is this abundance of food produced than there is an influx
from every side of consumers only too eager to abate this inordinate
production. The field-mouse, a native of the woods, stores acorns in a
gravel-heap near its hay-lined nest. A stranger, the jay, comes in
flocks from far away, warned I know not how. For some weeks it flies
feasting from oak to oak, giving vent to its joys and its emotions in a
voice like that of a strangling cat; then, its mission accomplished, it
returns to the North whence it came.
The Balaninus has anticipated them all. The mother confided her eggs to
the acorns while yet they were green. These have now fallen to earth,
brown before their time, and pierced by a round hole through which the
larva has escaped after devouring the contents. Under one single oak a
basket might easily be filled with these ruined shells. More than the
jay, more than the field-mouse, the elephant-beetle has contributed to
reduce the superfluity of acorns.
Presently man arrives, busied in the interest of his pig. In my village
it is quite an important event when the municipal hoardings announce the
day for opening the municipal woods for the gathering of acorns. The
more zealous visit the woods the day before and select the best places.
Next day, at daybreak, the whole family is there. The father beats the
upper branches with a pole; the mother, wearing a heavy hempen apron
which enables her to force her way through the stubborn undergrowth,
gathers those within reach of the hand, while the children collect those
scattered upon the ground. First the small baskets are filled, then the
big _corbeilles_, and then the sacks.
After the field-mouse, the jay, the weevil, and so many others have
taken toll comes man, calculating how many pounds of bacon-fat his
harvest will be worth. One regret mingles with the cheer of the
occasion; it is to see so many acorns scattered on the ground which are
pierced, spoiled, good for nothing. And man curses the author of this
destruction; to hear him you would think the forest is meant for him
alone, and that the oaks bear acorns only for the sake of his pig.
My friend, I would say to him, the forest guard cannot take legal
proceedings against the offender, and it is just as well, for our
egoism, which is inclined to see in the acorn only a garland of
sausages, would have annoying results. The oak calls the whole world to
enjoy its fruits. We take the larger part because we are the stronger.
That is our only right.
More important than our rights is the equitable division of the fruits
of the earth between the various consumers, great and little, all of
whom play their part in this world. If it is good that the blackbird
should flute and rejoice in the burgeoning of the spring, then it is no
bad thing that acorns should be worm-eaten. In the acorn the dessert of
the blackbird is prepared; the Balaninus, the tasty mouthful that puts
flesh upon his flanks and music into his throat.
Let the blackbird sing, and let us return to the eggs of the
Curculionidæ. We know where the egg is--at the base of the acorn,
because the tenderest and most juicy tissues of the fruit are there. But
how did it get there, so far from the point of entry? A very trifling
question, it is true; puerile even, if you will. Do not let us disdain
to ask it; science is made of these puerilities.
The first man to rub a piece of amber on his sleeve and to find that it
thereupon attracted fragments of chaff had certainly no vision of the
electric marvels of our days. He was amusing himself in a childlike
manner. Repeated, tested, and probed in every imaginable way, the
child's experiment has become one of the forces of the world.
The observer must neglect nothing; for he never knows what may develop
out of the humblest fact. So again we will ask: by what process did the
egg of the elephant-beetle reach a point so far from the orifice in the
acorn?
To one who was not already aware of the position of the egg, but knew
that the grub attacked the base of the acorn first, the solution of that
fact would be as follows: the egg is laid at the entrance of the tunnel,
at the surface, and the grub, crawling down the gallery sunk by the
mother, gains of its own accord this distant point where its infant diet
is to be found.
Before I had sufficient data this was my own belief; but the mistake was
soon exposed. I plucked an acorn just as the mother withdrew, after
having for a moment applied the tip of the abdomen to the orifice of the
passage just opened by her rostrum. The egg, so it seemed, must be
there, at the entrance of the passage.... But no, it was not! It was at
the other extremity of the passage! If I dared, I would say it had
dropped like a stone into a well.
That idea we must abandon at once; the passage is extremely narrow and
encumbered with shavings, so that such a thing would be impossible.
Moreover, according to the direction of the stem, accordingly as it
pointed upwards or downwards, the egg would have to fall downwards in
one acorn and upwards in another.
A second explanation suggests itself, not less perilous. It might be
said: "The cuckoo lays her egg on the grass, no matter where; she lifts
it in her beak and places it in the nearest appropriate nest." Might not
the Balaninus follow an analogous method? Does she employ the rostrum to
place the egg in its position at the base of the acorn? I cannot see
that the insect has any other implement capable of reaching this remote
hiding-place.
Nevertheless, we must hastily reject such an absurd explanation as a
last, desperate resort. The elephant-beetle certainly does not lay its
egg in the open and seize it in its beak. If it did so the delicate ovum
would certainly be destroyed, crushed in the attempt to thrust it down a
narrow passage half choked with debris.
This is very perplexing. My embarrassment will be shared by all readers
who are acquainted with the structure of the elephant-beetle. The
grasshopper has a sabre, an oviscapt which plunges into the earth and
sows the eggs at the desired depth; the Leuscopis has a probe which
finds its way through the masonry of the mason-bee and lays the egg in
the cocoon of the great somnolent larva; but the Balaninus has none of
these swords, daggers, or pikes; she has nothing but the tip of her
abdomen. Yet she has only to apply that abdominal extremity to the
opening of the passage, and the egg is immediately lodged at the very
bottom.
Anatomy will give us the answer to the riddle, which is otherwise
indecipherable. I open the body of a gravid female. There, before my
eyes, is something that takes my breath away. There, occupying the whole
length of the body, is an extraordinary device; a red, horny, rigid rod;
I had almost said a rostrum, so greatly does it resemble the implement
which the insect carries on his head. It is a tube, fine as a horsehair,
slightly enlarged at the free extremity, like an old-fashioned
blunderbuss, and expanding to form an egg-shaped capsule at the point of
origin.
This is the oviduct, and its dimensions are the same as those of the
rostrum. As far as the perforating beak can plunge, so far the oviscapt,
the interior rostrum, will reach. When working upon her acorn the female
chooses the point of attack so that the two complementary instruments
can each of them reach the desired point at the base of the acorn.
The matter now explains itself. The work of drilling completed, the
gallery ready, the mother turns and places the tip of the abdomen
against the orifice. She extrudes the internal mechanism, which easily
passes through the loose debris of the boring. No sign of the probe
appears, so quickly and discreetly does it work; nor is any trace of it
to be seen when, the egg having been properly deposited, the implement
ascends and returns to the abdomen. It is over, and the mother departs,
and we have not caught a glimpse of her internal mechanism.
Was I not right to insist? An apparently insignificant fact has led to
the authentic proof of a fact that the Larinidæ had already made me
suspect. The long-beaked weevils have an internal probe, an abdominal
rostrum, which nothing in their external appearance betrays; they
possess, among the hidden organs of the abdomen, the counterpart of the
grasshopper's sabre and the ichneumon's dagger.
CHAPTER XVIII
THE PEA-WEEVIL--_BRUCHUS PISI_
Peas are held in high esteem by mankind. From remote ages man has
endeavoured, by careful culture, to produce larger, tenderer, and
sweeter varieties. Of an adaptable character, under careful treatment
the plant has evolved in a docile fashion, and has ended by giving us
what the ambition of the gardener desired. To-day we have gone far
beyond the yield of the Varrons and Columelles, and further still beyond
the original pea; from the wild seeds confided to the soil by the first
man who thought to scratch up the surface of the earth, perhaps with the
half-jaw of a cave-bear, whose powerful canine tooth would serve him as
a ploughshare!
Where is it, this original pea, in the world of spontaneous vegetation?
Our own country has nothing resembling it. Is it to be found elsewhere?
On this point botany is silent, or replies only with vague
probabilities.
We find the same ignorance elsewhere on the subject of the majority of
our alimentary vegetables. Whence comes wheat, the blessed grain which
gives us bread? No one knows. You will not find it here, except in the
care of man; nor will you find it abroad. In the East, the birthplace
of agriculture, no botanist has ever encountered the sacred ear growing
of itself on unbroken soil.
Barley, oats, and rye, the turnip and the beet, the beetroot, the
carrot, the pumpkin, and so many other vegetable products, leave us in
the same perplexity; their point of departure is unknown to us, or at
most suspected behind the impenetrable cloud of the centuries. Nature
delivered them to us in the full vigour of the thing untamed, when their
value as food was indifferent, as to-day she offers us the sloe, the
bullace, the blackberry, the crab; she gave them to us in the state of
imperfect sketches, for us to fill out and complete; it was for our
skill and our labour patiently to induce the nourishing pulp which was
the earliest form of capital, whose interest is always increasing in the
primordial bank of the tiller of the soil.
As storehouses of food the cereal and the vegetable are, for the greater
part, the work of man. The fundamental species, a poor resource in their
original state, we borrowed as they were from the natural treasury of
the vegetable world; the perfected race, rich in alimentary materials,
is the result of our art.
If wheat, peas, and all the rest are indispensable to us, our care, by a
just return, is absolutely necessary to them. Such as our needs have
made them, incapable of resistance in the bitter struggle for survival,
these vegetables, left to themselves without culture, would rapidly
disappear, despite the numerical abundance of their seeds, as the
foolish sheep would disappear were there no more sheep-folds.
They are our work, but not always our exclusive property. Wherever food
is amassed, the consumers collect from the four corners of the sky; they
invite themselves to the feast of abundance, and the richer the food the
greater their numbers. Man, who alone is capable of inducing agrarian
abundance, is by that very fact the giver of an immense banquet at which
legions of feasters take their place. By creating more juicy and more
generous fruits he calls to his enclosures, despite himself, thousands
and thousands of hungry creatures, against whose appetites his
prohibitions are helpless. The more he produces, the larger is the
tribute demanded of him. Wholesale agriculture and vegetable abundance
favour our rival the insect.
This is the immanent law. Nature, with an equal zeal, offers her mighty
breast to all her nurslings alike; to those who live by the goods of
others no less than to the producers. For us, who plough, sow, and reap,
and weary ourselves with labour, she ripens the wheat; she ripens it
also for the little Calender-beetle, which, although exempted from the
labour of the fields, enters our granaries none the less, and there,
with its pointed beak, nibbles our wheat, grain by grain, to the husk.
For us, who dig, weed, and water, bent with fatigue and burned by the
sun, she swells the pods of the pea; she swells them also for the
weevil, which does no gardener's work, yet takes its share of the
harvest at its own hour, when the earth is joyful with the new life of
spring.
Let us follow the manoeuvres of this insect which takes its tithe of
the green pea. I, a benevolent ratepayer, will allow it to take its
dues; it is precisely to benefit it that I have sown a few rows of the
beloved plant in a corner of my garden. Without other invitation on my
part than this modest expenditure of seed-peas it arrives punctually
during the month of May. It has learned that this stony soil, rebellious
to the culture of the kitchen-gardener, is bearing peas for the first
time. In all haste therefore it has hurried, an agent of the
entomological revenue system, to demand its dues.
Whence does it come? It is impossible to say precisely. It has come from
some shelter, somewhere, in which it has passed the winter in a state of
torpor. The plane-tree, which sheds its rind during the heats of the
summer, furnishes an excellent refuge for homeless insects under its
partly detached sheets of bark.
I have often found our weevil in such a winter refuge. Sheltered under
the dead covering of the plane, or otherwise protected while the winter
lasts, it awakens from its torpor at the first touch of a kindly sun.
The almanack of the instincts has aroused it; it knows as well as the
gardener when the pea-vines are in flower, and seeks its favourite
plant, journeying thither from every side, running with quick, short
steps, or nimbly flying.
A small head, a fine snout, a costume of ashen grey sprinkled with
brown, flattened wing-covers, a dumpy, compact body, with two large
black dots on the rear segment--such is the summary portrait of my
visitor. The middle of May approaches, and with it the van of the
invasion.
They settle on the flowers, which are not unlike white-winged
butterflies. I see them at the base of the blossom or inside the cavity
of the "keel" of the flower, but the majority explore the petals and
take possession of them. The time for laying the eggs has not yet
arrived. The morning is mild; the sun is warm without being oppressive.
It is the moment of nuptial flights; the time of rejoicing in the
splendour of the sunshine. Everywhere are creatures rejoicing to be
alive. Couples come together, part, and re-form. When towards noon the
heat becomes too great, the weevils retire into the shadow, taking
refuge singly in the folds of the flowers whose secret corners they know
so well. To-morrow will be another day of festival, and the next day
also, until the pods, emerging from the shelter of the "keel" of the
flower, are plainly visible, enlarging from day to day.
A few gravid females, more pressed for time than the others, confide
their eggs to the growing pod, flat and meagre as it issues from its
floral sheath. These hastily laid batches of eggs, expelled perhaps by
the exigencies of an ovary incapable of further delay, seem to me in
serious danger; for the seed in which the grub must establish itself is
as yet no more than a tender speck of green, without firmness and
without any farinaceous tissue. No larva could possible find sufficient
nourishment there, unless it waited for the pea to mature.
But is the grub capable of fasting for any length of time when once
hatched? It is doubtful. The little I have seen tells me that the
new-born grub must establish itself in the midst of its food as quickly
as possible, and that it perishes unless it can do so. I am therefore of
opinion that such eggs as are deposited in immature pods are lost.
However, the race will hardly suffer by such a loss, so fertile is the
little beetle. We shall see directly how prodigal the female is of her
eggs, the majority of which are destined to perish.
The important part of the maternal task is completed by the end of May,
when the shells are swollen by the expanding peas, which have reached
their final growth, or are but little short of it. I was anxious to see
the female Bruchus at work in her quality of Curculionid, as our
classification declares her.[8] The other weevils are Rhyncophora,
beaked insects, armed with a drill with which to prepare the hole in
which the egg is laid. The Bruchus possesses only a short snout or
muzzle, excellently adapted for eating soft tissues, but valueless as a
drill.
The method of installing the family is consequently absolutely
different. There are no industrious preparations as with the Balinidæ,
the Larinidæ, and the Rhynchitides. Not being equipped with a long
oviscapt, the mother sows her eggs in the open, with no protection
against the heat of the sun and the variations of temperature. Nothing
could be simpler, and nothing more perilous to the eggs, in the absence
of special characteristics which would enable them to resist the
alternate trials of heat and cold, moisture and drought.
In the caressing sunlight of ten o'clock in the morning the mother runs
up and down the chosen pod, first on one side, then on the other, with a
jerky, capricious, unmethodical gait. She repeatedly extrudes a short
oviduct, which oscillates right and left as though to graze the skin of
the pod. An egg follows, which is abandoned as soon as laid.
A hasty touch of the oviduct, first here, then there, on the green skin
of the pea-pod, and that is all. The egg is left there, unprotected, in
the full sunlight. No choice of position is made such as might assist
the grub when it seeks to penetrate its larder. Some eggs are laid on
the swellings created by the peas beneath; others in the barren valleys
which separate them. The first are close to the peas, the second at some
distance from them. In short, the eggs of the Bruchus are laid at
random, as though on the wing.
We observe a still more serious vice: the number of eggs is out of all
proportion to the number of peas in the pod. Let us note at the outset
that each grub requires one pea; it is the necessary ration, and is
largely sufficient to one larva, but is not enough for several, nor even
for two. One pea to each grub, neither more nor less, is the
unchangeable rule.
We should expect to find signs of a procreative economy which would
impel the female to take into account the number of peas contained in
the pod which she has just explored; we might expect her to set a
numerical limit on her eggs in conformity with that of the peas
available. But no such limit is observed. The rule of one pea to one
grub is always contradicted by the multiplicity of consumers.
My observations are unanimous on this point. The number of eggs
deposited on one pod always exceeds the number of peas available, and
often to a scandalous degree. However meagre the contents of the pod
there is a superabundance of consumers. Dividing the sum of the eggs
upon such or such a pod by that of the peas contained therein, I find
there are five to eight claimants for each pea; I have found ten, and
there is no reason why this prodigality should not go still further.
Many are called, but few are chosen! What is to become of all these
supernumeraries, perforce excluded from the banquet for want of space?
The eggs are of a fairly bright amber yellow, cylindrical in form,
smooth, and rounded at the ends. Their length is at most a twenty-fifth
of an inch. Each is affixed to the pod by means of a slight network of
threads of coagulated albumen. Neither wind nor rain can loosen their
hold.
The mother not infrequently emits them two at a time, one above the
other; not infrequently, also, the uppermost of the two eggs hatches
before the other, while the latter fades and perishes. What was lacking
to this egg, that it should fail to produce a grub? Perhaps a bath of
sunlight; the incubating heat of which the outer egg has robbed it.
Whether on account of the fact that it is shadowed by the other egg, or
for other reasons, the elder of the eggs in a group of two rarely
follows the normal course, but perishes on the pod, dead without having
lived.
There are exceptions to this premature end; sometimes the two eggs
develop equally well; but such cases are exceptional, so that the
Bruchid family would be reduced to about half its dimensions if the
binary system were the rule. To the detriment of our peas and to the
advantage of the beetle, the eggs are commonly laid one by one and in
isolation.
A recent emergence is shown by a little sinuous ribbon-like mark, pale
or whitish, where the skin of the pod is raised and withered, which
starts from the egg and is the work of the new-born larva; a
sub-epidermic tunnel along which the grub works its way, while seeking a
point from which it can escape into a pea. This point once attained, the
larva, which is scarcely a twenty-fifth of an inch in length, and is
white with a black head, perforates the envelope and plunges into the
capacious hollow of the pod.
It has reached the peas and crawls upon the nearest. I have observed it
with the magnifier. Having explored the green globe, its new world, it
begins to sink a well perpendicularly into the sphere. I have often seen
it half-way in, wriggling its tail in the effort to work the quicker. In
a short time the grub disappears and is at home. The point of entry,
minute, but always easily recognisable by its brown coloration on the
pale green background of the pea, has no fixed location; it may be at
almost any point on the surface of the pea, but an exception is usually
made of the lower half; that is, the hemisphere whose pole is formed by
the supporting stem.
It is precisely in this portion that the germ is found, which will not
be eaten by the larva, and will remain capable of developing into a
plant, in spite of the large aperture made by the emergence of the adult
insect. Why is this particular portion left untouched? What are the
motives that safeguard the germ?
It goes without saying that the Bruchus is not considering the gardener.
The pea is meant for it and for no one else. In refusing the few bites
that would lead to the death of the seed, it has no intention of
limiting its destruction. It abstains from other motives.
Let us remark that the peas touch laterally, and are pressed one
against the other, so that the grub, when searching for a point of
attack, cannot circulate at will. Let us also note that the lower pole
expands into the umbilical excrescence, which is less easy of
perforation than those parts protected by the skin alone. It is even
possible that the umbilicum, whose organisation differs from that of the
rest of the pea, contains a peculiar sap that is distasteful to the
little grub.
Such, doubtless, is the reason why the peas exploited by the Bruchus are
still able to germinate. They are damaged, but not dead, because the
invasion was conducted from the free hemisphere, a portion less
vulnerable and more easy of access. Moreover, as the pea in its entirety
is too large for a single grub to consume, the consumption is limited to
the portion preferred by the consumer, and this portion is not the
essential portion of the pea.
With other conditions, with very much smaller or very much larger seeds,
we shall observe very different results. If too small, the germ will
perish, gnawed like the rest by the insufficiently provisioned inmate;
if too large, the abundance of food will permit of several inmates.
Exploited in the absence of the pea, the cultivated vetch and the broad
bean afford us an excellent example; the smaller seed, of which all but
the skin is devoured, is left incapable of germination; but the large
bean, even though it may have held a number of grubs, is still capable
of sprouting.
Knowing that the pod always exhibits a number of eggs greatly in excess
of the enclosed peas, and that each pea is the exclusive property of one
grub, we naturally ask what becomes of the superfluous grubs. Do they
perish outside when the more precocious have one by one taken their
places in their vegetable larder? or do they succumb to the intolerant
teeth of the first occupants? Neither explanation is correct. Let us
relate the facts.
On all old peas--they are at this stage dry--from which the adult
Bruchus has emerged, leaving a large round hole of exit, the
magnifying-glass will show a variable number of fine reddish
punctuations, perforated in the centre. What are these spots, of which I
count five, six, and even more on a single pea? It is impossible to be
mistaken: they are the points of entry of as many grubs. Several grubs
have entered the pea, but of the whole group only one has survived,
fattened, and attained the adult age. And the others? We shall see.
At the end of May, and in June, the period of egg-laying, let us inspect
the still green and tender peas. Nearly all the peas invaded show us the
multiple perforations already observed on the dry peas abandoned by the
weevils. Does this actually mean that there are several grubs in the
pea? Yes. Skin the peas in question, separate the cotyledons, and break
them up as may be necessary. We shall discover several grubs, extremely
youthful, curled up comma-wise, fat and lively, each in a little round
niche in the body of the pea.
Peace and welfare seem to reign in the little community. There is no
quarrelling, no jealousy between neighbours. The feast has commenced;
food is abundant, and the feasters are separated one from another by the
walls of uneaten substance. With this isolation in separate cells no
conflicts need be feared; no sudden bite of the mandibles, whether
intentional or accidental. All the occupants enjoy the same rights of
property, the same appetite, and the same strength. How does this
communal feast terminate?
Having first opened them, I place a number of peas which are found to be
well peopled in a glass test-tube. I open others daily. In this way I
keep myself informed as to the progress of the various larvæ. At first
nothing noteworthy is to be seen. Isolated in its narrow chamber, each
grub nibbles the substance around it, peacefully and parsimoniously. It
is still very small; a mere speck of food is a feast; but the contents
of one pea will not suffice the whole number to the end. Famine is
ahead, and all but one must perish.
Soon, indeed, the aspect of things is entirely changed. One of the
grubs--that which occupies the central position in the pea--begins to
grow more quickly than the others. Scarcely has it surpassed the others
in size when the latter cease to eat, and no longer attempt to burrow
forwards. They lie motionless and resigned; they die that gentle death
which comes to unconscious lives. Henceforth the entire pea belongs to
the sole survivor. Now what has happened that these lives around the
privileged one should be thus annihilated? In default of a satisfactory
reply, I will propose a suggestion.
In the centre of the pea, less ripened than the rest of the seed by the
chemistry of the sun, may there not be a softer pulp, of a quality
better adapted to the infantile digestion of the grub? There, perhaps,
being nourished by tenderer, sweeter, and perhaps more tasty tissues,
the stomach becomes more vigorous, until it is fit to undertake less
easily digested food. A nursling is fed on milk before proceeding to
bread and broth. May not the central portion of the pea be the
feeding-bottle of the Bruchid?
With equal rights, fired by an equal ambition, all the occupants of the
pea bore their way towards the delicious morsel. The journey is
laborious, and the grubs must rest frequently in their provisional
niches. They rest; while resting they frugally gnaw the riper tissues
surrounding them; they gnaw rather to open a way than to fill their
stomachs.
Finally one of the excavators, favoured by the direction taken, attains
the central portion. It establishes itself there, and all is over; the
others have only to die. How are they warned that the place is taken? Do
they hear their brother gnawing at the walls of his lodging? can they
feel the vibration set up by his nibbling mandibles? Something of the
kind must happen, for from that moment they make no attempt to burrow
further. Without struggling against the fortunate winner, without
seeking to dislodge him, those which are beaten in the race give
themselves up to death. I admire this candid resignation on the part of
the departed.
Another condition--that of space--is also present as a factor. The
pea-weevil is the largest of our Bruchidæ. When it attains the adult
stage it requires a certain amplitude of lodging, which the other
weevils do not require in the same degree. A pea provides it with a
sufficiently spacious cell; nevertheless, the cohabitation of two in one
pea would be impossible; there would be no room, even were the two to
put up with a certain discomfort. Hence the necessity of an inevitable
decimation, which will suppress all the competitors save one.
Now the superior volume of the broad bean, which is almost as much
beloved by the weevil as the pea, can lodge a considerable community,
and the solitary can live as a cenobite. Without encroaching on the
domain of their neighbours, five or six or more can find room in the one
bean.
Moreover, each grub can find its infant diet; that is, that layer which,
remote from the surface, hardens only gradually and remains full of sap
until a comparatively late period. This inner layer represents the crumb
of a loaf, the rest of the bean being the crust.
In the pea, a sphere of much less capacity, it occupies the central
portion; a limited point at which the grub develops, and lacking which
it perishes; but in the bean it lines the wide adjoining faces of the
two flattened cotyledons. No matter where the point of attack is made,
the grub has only to bore straight down when it quickly reaches the
softer tissues. What is the result? I have counted the eggs adhering to
a bean-pod and the beans included in the pod, and comparing the two
figures I find that there is plenty of room for the whole family at the
rate of five or six dwellers in each bean. No superfluous larvæ perish
of hunger when barely issued from the egg; all have their share of the
ample provision; all live and prosper. The abundance of food balances
the prodigal fertility of the mother.
If the Bruchus were always to adopt the broad bean for the establishment
of her family I could well understand the exuberant allowance of eggs to
one pod; a rich food-stuff easily obtained evokes a large batch of
eggs. But the case of the pea perplexes me. By what aberration does the
mother abandon her children to starvation on this totally insufficient
vegetable? Why so many grubs to each pea when one pea is sufficient only
for one grub?
Matters are not so arranged in the general balance-sheet of life. A
certain foresight seems to rule over the ovary so that the number of
mouths is in proportion to the abundance or scarcity of the food
consumed. The Scarabæus, the Sphex, the Necrophorus, and other insects
which prepare and preserve alimentary provision for their families, are
all of a narrowly limited fertility, because the balls of dung, the dead
or paralysed insects, or the buried corpses of animals on which their
offspring are nourished are provided only at the cost of laborious
efforts.
The ordinary bluebottle, on the contrary, which lays her eggs upon
butcher's meat or carrion, lays them in enormous batches. Trusting in
the inexhaustible riches represented by the corpse, she is prodigal of
offspring, and takes no account of numbers. In other cases the provision
is acquired by audacious brigandage, which exposes the newly born
offspring to a thousand mortal accidents. In such cases the mother
balances the chances of destruction by an exaggerated flux of eggs. Such
is the case with the Meloides, which, stealing the goods of others under
conditions of the greatest peril, are accordingly endowed with a
prodigious fertility.
The Bruchus knows neither the fatigues of the laborious, obliged to
limit the size of her family, nor the misfortunes of the parasite,
obliged to produce an exaggerated number of offspring. Without painful
search, entirely at her ease, merely moving in the sunshine over her
favourite plant, she can ensure a sufficient provision for each of her
offspring; she can do so, yet is foolish enough to over-populate the pod
of the pea; a nursery insufficiently provided, in which the great
majority will perish of starvation. This ineptitude is a thing I cannot
understand: it clashes too completely with the habitual foresight of the
maternal instinct.
I am inclined to believe that the pea is not the original food plant of
the Bruchus. The original plant must rather have been the bean, one seed
of which is capable of supporting half a dozen or more larvæ. With the
larger cotyledon the crying disproportion between the number of eggs and
the available provision disappears.
Moreover, it is indubitable that the bean is of earlier date than the
pea. Its exceptional size and its agreeable flavour would certainly have
attracted the attention of man from the remotest periods. The bean is a
ready-made mouthful, and would be of the greatest value to the hungry
tribe. Primitive man would at an early date have sown it beside his
wattled hut. Coming from Central Asia by long stages, their wagons drawn
by shaggy oxen and rolling on the circular discs cut from the trunks of
trees, the early immigrants would have brought to our virgin land, first
the bean, then the pea, and finally the cereal, that best of safeguards
against famine. They taught us the care of herds, and the use of bronze,
the material of the first metal implement. Thus the dawn of civilisation
arose over France. With the bean did those ancient teachers also
involuntarily bring us the insect which to-day disputes it with us? It
is doubtful; the Bruchidæ seem to be indigenous. At all events, I find
them levying tribute from various indigenous plants, wild vegetables
which have never tempted the appetite of man. They abound in particular
upon the great forest vetch (_Lathyrus latifolius_), with its
magnificent heads of flowers and long handsome pods. The seeds are not
large, being indeed smaller than the garden pea; but eaten to the very
skin, as they invariably are, each is sufficient to the needs of its
grub.
We must not fail to note their number. I have counted more than twenty
in a single pod, a number unknown in the case of the pea, even in the
most prolific varieties. Consequently this superb vetch is in general
able to nourish without much loss the family confided to its pod.
Where the forest vetch is lacking, the Bruchus, none the less, bestows
its habitual prodigality of eggs upon another vegetable of similar
flavour, but incapable of nourishing all the grubs: for the example, the
travelling vetch (_Vicia peregrina_) or the cultivated vetch (_Vicia
sativa_). The number of eggs remains high even upon insufficient pods,
because the original food-plant offered a copious provision, both in the
multiplicity and the size of the seeds. If the Bruchus is really a
stranger, let us regard the bean as the original food-plant; if
indigenous, the large vetch.
Sometime in the remote past we received the pea, growing it at first in
the prehistoric vegetable garden which already supplied the bean. It was
found a better article of diet than the broad bean, which to-day, after
such good service, is comparatively neglected. The weevil was of the
same opinion as man, and without entirely forgetting the bean and the
vetch it established the greater part of its tribe upon the pea, which
from century to century was more widely cultivated. To-day we have to
share our peas: the Bruchidæ take what they need, and bestow their
leavings on us.
This prosperity of the insect which is the offspring of the abundance
and quality of our garden products is from another point of view
equivalent to decadence. For the weevil, as for ourselves, progress in
matters of food and drink is not always beneficial. The race would
profit better if it remained frugal. On the bean and the vetch the
Bruchus founded colonies in which the infant mortality was low. There
was room for all. On the pea-vine, delicious though its fruits may be,
the greater part of its offspring die of starvation. The rations are
few, and the hungry mouths are multitudinous.
We will linger over this problem no longer. Let us observe the grub
which has now become the sole tenant of the pea by the death of its
brothers. It has had no part in their death; chance has favoured it,
that is all. In the centre of the pea, a wealthy solitude, it performs
the duty of a grub; the sole duty of eating. It nibbles the walls
enclosing it, enlarging its lodgment, which is always entirely filled by
its corpulent body. It is well shaped, fat, and shining with health. If
I disturb it, it turns gently in its niche and sways its head. This is
its manner of complaining of my importunities. Let us leave it in peace.
It profits so greatly and so swiftly by its position that by the time
the dog-days have come it is already preparing for its approaching
liberation. The adult is not sufficiently well equipped to open for
itself a way out through the pea, which is now completely hardened. The
larva knows of this future helplessness, and with consummate art
provides for its release. With its powerful mandibles it bores a channel
of exit, exactly round, with extremely clean-cut sides. The most skilful
ivory-carver could do no better.
To prepare the door of exit in advance is not enough; the grub must also
provide for the tranquillity essential to the delicate processes of
nymphosis. An intruder might enter by the open door and injure the
helpless nymph. This passage must therefore remain closed. But how?
As the grub bores the passage of exit it consumes the farinaceous matter
without leaving a crumb. Having come to the skin of the pea it stops
short. This membrane, semi-translucid, is the door to the chamber of
metamorphosis, its protection against the evil intentions of external
creatures.
It is also the only obstacle which the adult will encounter at the
moment of exit. To lessen the difficulty of opening it the grub takes
the precaution of gnawing at the inner side of the skin, all round the
circumference, so as to make a line of least resistance. The perfect
insect will only have to heave with its shoulder and strike a few blows
with its head in order to raise the circular door and knock it off like
the lid of a box. The passage of exit shows through the diaphanous skin
of the pea as a large circular spot, which is darkened by the obscurity
of the interior. What passes behind it is invisible, hidden as it is
behind a sort of ground glass window.
A pretty invention, this little closed porthole, this barricade against
the invader, this trap-door raised by a push when the time has come for
the hermit to enter the world. Shall we credit it to the Bruchus? Did
the ingenious insect conceive the undertaking? Did it think out a plan
and work out a scheme of its own devising? This would be no small
triumph for the brain of a weevil. Before coming to a conclusion let us
try an experiment.
I deprive certain occupied peas of their skin, and I dry them with
abnormal rapidity, placing them in glass test-tubes. The grubs prosper
as well as in the intact peas. At the proper time the preparations for
emergence are made.
If the grub acts on its own inspiration, if it ceases to prolong its
boring directly it recognises that the outer coating, auscultated from
time to time, is sufficiently thin, what will it do under the conditions
of the present test? Feeling itself at the requisite distance from the
surface it will stop boring; it will respect the outer layer of the bare
pea, and will thus obtain the indispensable protecting screen.
Nothing of the kind occurs. In every case the passage is completely
excavated; the entrance gapes wide open, as large and as carefully
executed as though the skin of the pea were in its place. Reasons of
security have failed to modify the usual method of work. This open
lodging has no defence against the enemy; but the grub exhibits no
anxiety on this score.
Neither is it thinking of the outer enemy when it bores down to the skin
when the pea is intact, and then stops short. It suddenly stops because
the innutritious skin is not to its taste. We ourselves remove the
parchment-like skins from a mess of pease-pudding, as from a culinary
point of view they are so much waste matter. The larva of the Bruchus,
like ourselves, dislikes the skin of the pea. It stops short at the
horny covering, simply because it is checked by an uneatable substance.
From this aversion a little miracle arises; but the insect has no sense
of logic; it is passively obedient to the superior logic of facts. It
obeys its instinct, as unconscious of its act as is a crystal when it
assembles, in exquisite order, its battalions of atoms.
Sooner or later during the month of August we see a shadowy circle form
on each inhabited pea; but only one on each seed. These circles of
shadow mark the doors of exit. Most of them open in September. The lid,
as though cut out with a punch, detaches itself cleanly and falls to the
ground, leaving the orifice free. The Bruchus emerges, freshly clad, in
its final form.
The weather is delightful. Flowers are abundant, awakened by the summer
showers; and the weevils visit them in the lovely autumn weather. Then,
when the cold sets in, they take up their winter quarters in any
suitable retreat. Others, still numerous, are less hasty in quitting the
native seed. They remain within during the whole winter, sheltered
behind the trap-door, which they take care not to touch. The door of the
cell will not open on its hinges, or, to be exact, will not yield along
the line of least resistance, until the warm days return. Then the late
arrivals will leave their shelter and rejoin the more impatient, and
both will be ready for work when the pea-vines are in flower.
To take a general view of the instincts in their inexhaustible variety
is, for the observer, the great attraction of the entomological world;
for nowhere do we gain a clearer sight of the wonderful way in which the
processes of life are ordered. Thus regarded entomology is not, I know,
to the taste of everybody; the simple creature absorbed in the doings
and habits of insects is held in low esteem. To the terrible
utilitarian, a bushel of peas preserved from the weevil is of more
importance than a volume of observations which bring no immediate
profit.
Yet who has told you, O man of little faith, that what is useless to-day
will not be useful to-morrow? If we learn the customs of insects or
animals we shall understand better how to protect our goods. Do not
despise disinterested knowledge, or you may rue the day. It is by the
accumulation of ideas, whether immediately applicable or otherwise, that
humanity has done, and will continue to do, better to-day than
yesterday, and better to-morrow than to-day. If we live on peas and
beans, which we dispute with the weevil, we also live by knowledge, that
mighty kneading-trough in which the bread of progress is mixed and
leavened. Knowledge is well worth a few beans.
Among other things, knowledge tells us: "The seedsman need not go to the
expense of waging war upon the weevil. When the peas arrive in the
granary, the harm is already done; it is irreparable, but not
transmissible. The untouched peas have nothing to fear from the
neighbourhood of those which have been attacked, however long the
mixture is left. From the latter the weevils will issue when their time
has come; they will fly away from the storehouse if escape is possible;
if not, they will perish without in any way attacking the sound peas. No
eggs, no new generation will ever be seen upon or within the dried peas
in the storehouse; there the adult weevil can work no further mischief."
The Bruchus is not a sedentary inhabitant of granaries: it requires the
open air, the sun, the liberty of the fields. Frugal in everything, it
absolutely disdains the hard tissues of the vegetable; its tiny mouth is
content with a few honeyed mouthfuls, enjoyed upon the flowers. The
larvæ, on the other hand, require the tender tissues of the green pea
growing in the pod. For these reasons the granary knows no final
multiplication on the part of the despoiler.
The origin of the evil is in the kitchen-garden. It is there that we
ought to keep a watch on the misdeeds of the Bruchus, were it not for
the fact that we are nearly always weaponless when it comes to fighting
an insect. Indestructible by reason of its numbers, its small size, and
its cunning, the little creature laughs at the anger of man. The
gardener curses it, but the weevil is not disturbed: it imperturbably
continues its trade of levying tribute. Happily we have assistants more
patient and more clear-sighted than ourselves.
During the first week of August, when the mature Bruchus begins to
emerge, I notice a little Chalcidian, the protector of our peas. In my
rearing-cages it issues under my eyes in abundance from the peas
infested by the grub of the weevil. The female has a reddish head and
thorax; the abdomen is black, with a long augur-like oviscapt. The male,
a little smaller, is black. Both sexes have reddish claws and
thread-like antennæ.
In order to escape from the pea the slayer of the weevil makes an
opening in the centre of the circular trap-door which the grub of the
weevil prepared in view of its future deliverance. The slain has
prepared the way for the slayer. After this detail the rest may be
divined.
When the preliminaries to the metamorphosis are completed, when the
passage of escape is bored and furnished with its lid of superficial
membrane, the female Chalcidian arrives in a busy mood. She inspects the
peas, still on the vine, and enclosed in their pods; she auscultates
them with her antennæ; she discovers, hidden under the general envelope,
the weak points in the epidermic covering of the peas. Then, applying
her oviscapt, she thrusts it through the side of the pod and perforates
the circular trap-door. However far withdrawn into the centre of the
pea, the Bruchus, whether larvæ or nymph, is reached by the long
oviduct. It receives an egg in its tender flesh, and the thing is done.
Without possibility of defence, since it is by now a somnolent grub or a
helpless pupa, the embryo weevil is eaten until nothing but skin
remains. What a pity that we cannot at will assist the multiplication of
this eager exterminator! Alas! our assistants have got us in a vicious
circle, for if we wished to obtain the help of any great number of
Chalcidians we should be obliged in the first place to breed a
multiplicity of Bruchidæ.
CHAPTER XIX
AN INVADER.--THE HARICOT-WEEVIL
If there is one vegetable on earth that more than any other is a gift of
the gods, it is the haricot bean. It has all the virtues: it forms a
soft paste upon the tongue; it is extremely palatable, abundant,
inexpensive, and highly nutritious. It is a vegetable meat which,
without being bloody and repulsive, is the equivalent of the horrors
outspread upon the butcher's slab. To recall its services the more
emphatically, the Provençal idiom calls it the _gounflo-gus_--the filler
of the poor.
Blessed Bean, consoler of the wretched, right well indeed do you fill
the labourer, the honest, skilful worker who has drawn a low number in
the crazy lottery of life. Kindly Haricot, with three drops of oil and a
dash of vinegar you were the favourite dish of my young years; and even
now, in the evening of my days, you are welcome to my humble porringer.
We shall be friends to the last.
To-day it is not my intention to sing your merits; I wish simply to ask
you a question, being curious: What is the country of your origin? Did
you come from Central Asia with the broad bean and the pea? Did you make
part of that collection of seeds which the first pioneers of culture
brought us from their gardens? Were you known to antiquity?
Here the insect, an impartial and well-informed witness, answers: "No;
in our country antiquity was not acquainted with the haricot. The
precious vegetable came hither by the same road as the broad bean. It is
a foreigner, and of comparatively recent introduction into Europe."
The reply of the insect merits serious examination, supported as it is
by extremely plausible arguments. Here are the facts. For years
attentive to matters agricultural, I had never seen haricots attacked by
any insect whatever; not even by the Bruchidæ, the licensed robbers of
leguminous seeds.
On this point I have questioned my peasant neighbours. They are men of
the extremest vigilance in all that concerns their crops. To steal their
property is an abominable crime, swiftly discovered. Moreover, the
housewife, who individually examines all beans intended for the
saucepan, would inevitably find the malefactor.
All those I have spoken to replied to my questions with a smile in which
I read their lack of faith in my knowledge of insects. "Sir," they said,
"you must know that there are never grubs in the haricot bean. It is a
blessed vegetable, respected by the weevil. The pea, the broad bean, the
vetch, and the chick-pea all have their vermin; but the haricot, _lou
gounflo-gus_, never. What should we do, poor folk as we are, if the
_Courcoussoun_ robbed us of it?"
The fact is that the weevil despises the haricot; a very curious dislike
if we consider how industriously the other vegetables of the same family
are attacked. All, even the beggarly lentil, are eagerly exploited;
whilst the haricot, so tempting both as to size and flavour, remains
untouched. It is incomprehensible. Why should the Bruchus, which without
hesitation passes from the excellent to the indifferent, and from the
indifferent to the excellent, disdain this particularly toothsome seed?
It leaves the forest vetch for the pea, and the pea for the broad bean,
as pleased with the small as with the large, yet the temptations of the
haricot bean leave it indifferent. Why?
Apparently because the haricot is unknown to it. The other leguminous
plants, whether native or of Oriental origin, have been familiar to it
for centuries; it has tested their virtues year by year, and, confiding
in the lessons of the past, it bases its forethought for the future upon
ancient custom. The haricot is avoided as a newcomer, whose merits it
has not yet learned.
The insect emphatically informs us that with us the haricot is of recent
date. It has come to us from a distant country: and assuredly from the
New World. Every edible vegetable attracts its consumers. If it had
originated in the Old World the haricot would have had its licensed
consumers, as have the pea, the lentil, and the broad bean. The smallest
leguminous seed, if barely bigger than a pin's head, nourishes its
weevil; a dwarf which patiently nibbles it and excavates a dwelling; but
the plump, delicious haricot is spared.
This astonishing immunity can have only one explanation: like the potato
and the maize-plant, the haricot is a gift of the New World. It arrived
in Europe without the company of the insect which exploits it in its
native country; it has found in our fields another world of insects,
which have despised it because they did not know it. Similarly the
potato and the ear of maize are untouched in France unless their
American consumers are accidentally imported with them.
The verdict of the insect is confirmed by the negative testimony of the
ancient classics; the haricot never appears on the table of the Greek or
Roman peasant. In the second Eclogue of Virgil Thestylis prepares the
repast of the harvesters:--
Thestylis et rapido fessis messoribus æstu
Allia serpyllumque herbas contundit olentes.
This mixture is the equivalent of the _aïoli_, dear to the Provençal
palate. It sounds very well in verse, but is not very substantial. On
such an occasion men would look for that fundamental dish, the plate of
red haricots, seasoned with chopped onions. All in good time; this at
least would ballast the stomach. Thus refreshed in the open air,
listening to the song of the cigales, the gang of harvesters would take
their mid-day rest and gently digest their meal in the shadows of the
sheaves. Our modern Thestylis, differing little from her classic sister,
would take good care not to forget the _gounflo-gus_, that economical
resource of large appetites. The Thestylis of the past did not think of
providing it because she did not know it.
The same author shows us Tityrus offering a night's hospitality to his
friend Meliboeus, who has been driven from his property by the
soldiers of Octavius, and goes limping behind his flock of goats. We
shall have, says Tityrus, chestnuts, cheese, and fruits. History does
not say if Meliboeus allowed himself to be tempted. It is a pity; for
during the frugal meal we might have learned in a more explicit fashion
that the shepherds of the ancient world were not acquainted with the
haricot.
Ovid tells us, in a delightful passage, of the manner in which Philemon
and Baucis received the gods unawares as guests in their humble cottage.
On the three-legged table, which was levelled by means of a potsherd
under one of the legs, they served cabbage soup, rusty bacon, eggs
poached for a minute in the hot cinders, cornel-berries pickled in
brine, honey, and fruits. In this rustic abundance one dish was lacking;
an essential dish, which the Baucis of our countryside would never
forget. After bacon soup would follow the obligatory plate of haricots.
Why did Ovid, so prodigal of detail, neglect to mention a dish so
appropriate to the occasion? The reply is the same as before: because he
did not know of it.
In vain have I recapitulated all that my reading has taught me
concerning the rustic dietary of ancient times; I can recollect no
mention of the haricot. The worker in the vineyard and the harvester
have their lupins, broad beans, peas, and lentils, but never the bean of
beans, the haricot.
The haricot has a reputation of another kind. It is a source of
flatulence; you eat it, as the saying is, and then you take a walk. It
lends itself to the gross pleasantries loved of the populace; especially
when they are formulated by the shameless genius of an Aristophanes or a
Plautus. What merriment over a simple allusion to the sonorous bean,
what guffaws from the throats of Athenian sailors or Roman porters! Did
the two masters, in the unfettered gaiety of a language less reserved
than our own, ever mention the virtues of the haricot? No; they are
absolutely silent concerning the trumpet-voiced vegetable.
The name of the bean is a matter for reflection. It is of an unfamiliar
sound, having no affinity with our language. By its unlikeness to our
native combinations of sounds, it makes one think of the West Indies or
South America, as do _caoutchouc_ and _cacao_. Does the word as a matter
of fact come from the American Indians? Did we receive, together with
the vegetable, the name by which it is known in its native country?
Perhaps; but how are we to know? Haricot, fantastic haricot, you set us
a curious philological problem.
It is also known in French as _faséole_, or _flageolet_. The Provençal
calls it _faioù_ and _favioù_; the Catalan, _fayol_; the Spaniard,
_faseolo_; the Portuguese, _feyâo_; the Italian, _fagiuolo_. Here I am
on familiar ground: the languages of the Latin family have preserved,
with the inevitable modifications, the ancient word _faseolus_.
Now, if I consult my dictionary I find: _faselus_, _faseolus_,
_phaseolus_, haricot. Learned lexicographer, permit me to remark that
your translation is incorrect: _faselus_, _faseolus_ cannot mean
haricot. The incontestable proof is in the Georgics, where Virgil tells
us at what season we must sow the _faselus_. He says:--
Si vero viciamque seres vilemque faselum ...
Haud obscura cadens mittet tibi signa Bootes;
Incipe, et ad medias sementem extende pruinas.
Nothing is clearer than the precept of the poet who was so admirably
familiar with all matters agricultural; the sowing of the _faselus_ must
be commenced when the constellation of Bootes disappears at the set of
sun, that is, in October; and it is to be continued until the middle of
the winter.
These conditions put the haricot out of the running: it is a delicate
plant, which would never survive the lightest frost. Winter would be
fatal to it, even under Italian skies. More refractory to cold on
account of the country of their origin, peas, broad beans, and vetches,
and other leguminous plants have nothing to fear from an autumn sowing,
and prosper during the winter provided the climate be fairly mild.
What then is represented by the _faselus_ of the Georgics, that
problematical vegetable which has transmitted its name to the haricot in
the Latin tongues? Remembering that the contemptuous epithet _vilis_ is
used by the poet in qualification, I am strongly inclined to regard it
as the cultivated vetch, the big square pea, the little-valued _jaïsso_
of the Provençal peasant.
The problem of the haricot stood thus, almost elucidated by the
testimony of the insect world alone, when an unexpected witness gave me
the last word of the enigma. It was once again a poet, and a famous
poet, M. José-Maria de Heredia, who came to the aid of the naturalist.
Without suspecting the service he was rendering, a friend of mine, the
village schoolmaster, lent me a magazine[9] in which I read the
following conversation between the master-sonneteer and a lady
journalist, who was anxious to know which of his own works he preferred.
"What would you have me say?" said the poet.
"I do not know what to say, I do not know which sonnet I prefer; I have
taken horrible pains with all of them.... But you, which do you prefer?"
"My dear master, how can I choose out of so many jewels, when each one
is perfect in its beauty? You flash pearls, emeralds, and rubies before
my astonished eyes: how should I decide to prefer the emerald to the
pearl? I am transported by admiration of the whole necklace."
"Well, as for me, there is something I am more proud of than of all my
sonnets, and which has done much more for my reputation than my verses."
I opened my eyes wide, "What is that?" I asked. The master looked at me
mischievously; then, with that beautiful light in his eyes which fires
his youthful countenance, he said triumphantly--
"It is my discovery of the etymology of the word haricot!"
I was so amazed that I forgot to laugh.
"I am perfectly serious in telling you this."
"I know, my dear master, of your reputation for profound scholarship:
but to imagine, on that account, that you were famed for your discovery
of the etymology of haricot--I should never have expected it! Will you
tell me how you made the discovery?"
"Willingly. See now: I found some information respecting the haricot
while studying that fine seventeenth-century work of natural history by
Hernandez: _De Historia plantarum novi orbis_. The word haricot was
unknown in France until the seventeenth century: people used the word
_feve_ or _phaséol_: in Mexican, _ayacot_. Thirty species of haricot
were cultivated in Mexico before the conquest. They are still known as
_ayacot_, especially the red haricot, spotted with black or violet. One
day at the house of Gaston Paris I met a famous scholar. Hearing my
name, he rushed at me and asked if it was I who had discovered the
etymology of the word haricot. He was absolutely ignorant of the fact
that I had written verses and published the _Trophées_."--
A very pretty whim, to count the jewellery of his famous sonnets as
second in importance to the nomenclature of a vegetable! I in my turn
was delighted with his _ayacot_. How right I was to suspect the
outlandish word of American Indian origin! How right the insect was, in
testifying, in its own fashion, that the precious bean came to us from
the New World! While still retaining its original name--or something
sufficiently like it--the bean of Montezuma, the Aztec _ayacot_, has
migrated from Mexico to the kitchen-gardens of Europe.
But it has reached us without the company of its licensed consumer; for
there must assuredly be a weevil in its native country which levies
tribute on its nourishing tissues. Our native bean-eaters have mistaken
the stranger; they have not had time as yet to grow familiar with it, or
to appreciate its merits; they have prudently abstained from touching
the _ayacot_, whose novelty awoke suspicion. Until our own days the
Mexican bean remained untouched: unlike our other leguminous seeds,
which are all eagerly exploited by the weevil.
This state of affairs could not last. If our own fields do not contain
the insect amateur of the haricot the New World knows it well enough. By
the road of commercial exchange, sooner or later some worm-eaten sack
of haricots must bring it to Europe. The invasion is inevitable.
According to documents now before me, indeed, it has already taken
place. Three or four years ago I received from Maillane, in the
Bouches-du-Rhône, what I sought in vain in my own neighbourhood,
although I questioned many a farmer and housewife, and astonished them
by my questions. No one had ever seen the pest of the haricot; no one
had ever heard of it. Friends who knew of my inquiries sent me from
Maillane, as I have said, information that gave great satisfaction to my
naturalist's curiosity. It was accompanied by a measure of haricots
which were utterly and outrageously spoiled; every bean was riddled with
holes, changed into a kind of sponge. Within them swarmed innumerable
weevils, which recalled, by their diminutive size, the lentil-weevil,
_Bruchus lenti_.
The senders told me of the loss experienced at Maillane. The odious
little creature, they said, had destroyed the greater portion of the
harvest. A veritable plague, such as had never before been known, had
fallen upon the haricots, leaving the housewife barely a handful to put
in the saucepan. Of the habits of the creature and its way of going to
work nothing was known. It was for me to discover them by means of
experiment.
Quick, then, let us experiment! The circumstances favour me. We are in
the middle of June, and in my garden there is a bed of early haricots;
the black Belgian haricots, sown for use in the kitchen. Since I must
sacrifice the toothsome vegetable, let us loose the terrible destroyer
on the mass of verdure. The development of the plant is at the
requisite stage, if I may go by what the _Bruchus pisi_ has already
taught me; the flowers are abundant, and the pods are equally so; still
green, and of all sizes.
I place on a plate two or three handfuls of the infested haricots, and
set the populous heap in the full sunlight by the edge of my bed of
beans. I can imagine what will happen. Those insects which are already
free, and those which the stimulus of the sunshine will presently
liberate, will emerge and take to their wings. Finding the maternal
haricot close at hand they will take possession of the vines. I shall
see them exploring pods and flowers, and before very long they will lay
their eggs. That is how the pea-weevil would behave under similar
conditions.
But no: to my surprise and confusion, matters do not fall out as I
foresaw. For a few minutes the insects bustle about in the sunlight,
opening and closing their wing-covers to ease the mechanism of flight;
then one by one they fly away, mounting in the luminous air; they grow
smaller and smaller to the sight, and are quickly lost to view. My
persevering attentions have not met with the slightest success; not one
of the weevils has settled on my haricots.
When the joys of liberty have been tasted will they return--to-night,
to-morrow, or later? No, they do not return. All that week, at
favourable hours, I inspect the rows of beans pod by pod, flower by
flower; but never a Bruchus do I see, nor even an egg. Yet the season is
propitious, for at this very moment the mothers imprisoned in my jars
lay a profusion of eggs upon the dry haricots.
Next season I try again. I have at my disposal two other beds, which I
have sown with the late haricot, the red haricot; partly for the use of
the household, but principally for the benefit of the weevil. Arranged
in convenient rows, the two crops will be ready, one in August and one
in September or later.
With the red haricot I repeat the experiment already essayed with the
black haricot. On several occasions, in suitable weather, I release
large numbers of weevils from my glass jars, the general headquarters of
the tribe. On each occasion the result is plainly negative. All through
the season, until both crops are exhausted, I repeat my search almost
daily; but I can never discover a single pod infested, nor even a single
weevil perching on leaf or flower.
Certainly the inspection has not been at fault. The household is warned
to respect certain rows of beans which I have reserved for myself. It is
also requested to keep a look-out for eggs on all the pods gathered. I
myself examine with a magnifying-glass all the haricots coming from my
own or from neighbouring gardens before handing them over to the
housewife to be shelled. All my trouble is wasted: there is not an egg
to be seen.
To these experiments in the open air I add others performed under glass.
I place, in some tall, narrow bottles, fresh haricot pods hanging from
their stems; some green, others mottled with crimson, and containing
seeds not far from mature. Each bottle is finally given a population of
weevils. This time I obtain some eggs, but I am no further advanced;
they are laid on the sides of the bottles, but not on the pods.
Nevertheless, they hatch. For a few days I see the grubs wandering
about, exploring the pods and the glass with equal zeal. Finally one
and all perish without touching the food provided.
The conclusion to be drawn from these facts is obvious: the young and
tender haricot is not the proper diet. Unlike the _Bruchus pisi_, the
female of the haricot-weevil refuses to trust her family to beans that
are not hardened by age and desiccation; she refused to settle on my
bean-patch because the food she required was not to be found there. What
does she require? Evidently the mature, dry, hard haricot, which falls
to earth with the sound of a small pebble. I hasten to satisfy her. I
place in the bottles some very mature, horny pods, thoroughly desiccated
by exposure to the sun. This time the family prospers, the grubs
perforate the dry shell, reach the beans, penetrate them, and henceforth
all goes well.
To judge by appearances, then, the weevil invades the granary. The beans
are left standing in the fields until both plants and pods, shrivelled
by the sun, are completely desiccated. The process of beating the pods
to loosen and separate the beans is thus greatly facilitated. It is then
that the weevil, finding matters to suit her, commences to lay her eggs.
By storing his crop a little late the peasant stores the pest as well.
But the weevil more especially attacks the haricot when warehoused. Like
the Calander-beetle, which nibbles the wheat in our granaries but
despises the cereal while still on the stalk, it abhors the bean while
tender, and prefers to establish itself in the peace and darkness of the
storehouse. It is a formidable enemy to the merchant rather than to the
peasant.
What a fury of destruction once the ravager is installed in the
vegetable treasure-house! My bottles give abundant evidence of this. One
single haricot bean shelters a numerous family; often as many as twenty
members. And not one generation only exploits the bean, but three or
four in the year. So long as the skin of the bean contains any edible
matter, so long do new consumers establish themselves within it, so that
the haricot finally becomes a mere shell stuffed with excreta. The skin,
despised by the grubs, is a mere sac, pierced with holes as many as the
inhabitants that have deserted it; the ruin is complete.
The _Bruchus pisi_, a solitary hermit, consumes only so much of the pea
as will leave a cell for the nymph; the rest remains intact, so that the
pea may be sown, or it will even serve as food, if we can overcome our
repugnance. The American insect knows nothing of these limitations; it
empties the haricot completely and leaves a skinful of filth that I have
seen the pigs refuse. America is anything but considerate when she sends
us her entomological pests. We owe the Phylloxera to America; the
Phylloxera, that calamitous insect against which our vine-growers wage
incessant war: and to-day she is sending us the haricot-weevil, which
threatens to be a plague of the future. A few experiments gave me some
idea of the peril of such an invasion.
For nearly three years there have stood, on my laboratory table, some
dozens of jars and bottles covered with pieces of gauze which prevent
escape while permitting of a constant ventilation. These are the cages
of my menagerie. In them I rear the haricot-weevil, varying the system
of education at will. Amongst other things I have learned that this
insect, far from being exclusive in its choice, will accommodate itself
to most of our leguminous foods.
All the haricots suit it, black and white, red and variegated, large and
small; those of the latest crop and those which have been many years in
stock and are almost completely refractory to boiling water. The loose
beans are attacked by preference, as being easier to invade, but when
the loose beans are not available those in the natural shelter of their
pods are attacked with equal zest. However dry and parchment-like the
pods, the grubs have no difficulty in attaining the seeds. When attacked
in the field or garden, the bean is attacked in this way through the
pod. The bean known in Provence as the blind haricot--_lou faioù
borgné_--a bean with a long pod, which is marked with a black spot at
the navel, which has the look of a closed and blackened eye, is also
greatly appreciated; indeed, I fancy my little guests show an obvious
preference for this particular bean.
So far, nothing abnormal; the Bruchus does not wander beyond the limits
of the botanical family _Phaseolus_. But here is a characteristic that
increases the peril, and shows us this lover of beans in an unexpected
light. Without the slightest hesitation it accepts the dry pea, the
bean, the vetch, the tare, and the chick-pea; it goes from one to the
other, always satisfied; its offspring live and prosper in all these
seeds as well as in the haricot. Only the lentil is refused, perhaps on
account of its insufficient volume. The American weevil is a formidable
experimentalist.
The peril would be much greater did the insect pass from leguminous
seeds to cereals, as at first I feared it might. But it does not do so;
imprisoned in my bottles together with a handful of wheat, barley, rice,
or maize, the Bruchus invariably perished and left no offspring. The
result was the same with oleaginous seeds: such as castor-oil and
sunflower. Nothing outside the bean family is of any use to the Bruchus.
Thus limited, its portion is none the less considerable, and it uses and
abuses it with the utmost energy. The eggs are white, slender, and
cylindrical. There is no method in their distribution, no choice in
their deposition. The mother lays them singly or in little groups, on
the walls of the jar as well as on the haricots. In her negligence she
will even lay them on maize, coffee, castor-oil seeds, and other seeds,
on which the newly born grubs will promptly perish, not finding them to
their taste. What place has maternal foresight here? Abandoned no matter
where in the heap of seeds, the eggs are always in place, as it is left
to the grub to search and to find the points of invasion.
In five days at most the egg is hatched. A little white creature with a
red-brown head emerges. It is a mere speck of a creature, just visible
to the naked eye. Its body is thickened forward, to give more strength
to its implements--its mandibles--which have to perforate the hard
substance of the dry bean, which is as tough as wood. The larvæ of the
Buprestis and the Capricornis, which burrow in the trunks of trees, are
similarly shaped. Directly it issues from the egg the wriggling creature
makes off at random with an activity we should hardly expect in one so
young. It wanders hither and thither, eager to find food and shelter as
soon as possible.
Within twenty-four hours it has usually attained both. I see the tiny
grub perforate the horny skin that covers the cotyledons; I watch its
efforts; I surprise it sunk half-way in the commencement of a burrow, at
the mouth of which is a white floury powder, the waste from the
mandibles. It works its way inward and buries itself in the heart of the
seed. It will emerge in the adult form in the course of about five
weeks, so rapid is its evolution.
This hasty development allows of several generations in the year. I have
recorded four. On the other hand, one isolated couple has furnished me
with a family of eighty. Consider only the half of this
number--supposing the sexes to be equal in number--and at the end of a
year the couples issued from this original pair would be represented by
the fortieth power of forty; in larvæ they would represent the frightful
total of more than five millions. What a mountain of haricots would be
ravaged by such a legion!
The industry of the larvæ reminds us at every point what we have learned
from the _Bruchus pisi_. Each grub excavates a lodging in the mass of
the bean, respecting the epidermis, and preparing a circular trap-door
which the adult can easily open with a push at the moment of emergence.
At the termination of the larval phase the lodgements are betrayed on
the surface of the bean by so many shadowy circles. Finally the lid
falls, the insect leaves its cell, and the haricot remains pierced by as
many holes as it has nourished grubs.
Extremely frugal, satisfied with a little farinaceous powder, the adults
seem by no means anxious to abandon the native heap or bin so long as
there are beans untouched. They mate in the interstices of the heap;
the mothers sow their eggs at random; the young larvæ establish
themselves some in beans that are so far intact, some in beans which are
perforated but not yet exhausted; and all through the summer the
operations of breeding are repeated once in every five weeks. The last
generation of the year--that of September or October--sleeps in its
cells until the warm weather returns.
If the haricot pest were ever to threaten us seriously it would not be
very difficult to wage a war of extermination against it. Its habits
teach us what tactics we ought to follow. It exploits the dried and
gathered crop in the granary or the storehouse. If it is difficult to
attack it in the open it would also be useless. The greater part of its
affairs are managed elsewhere, in our storehouses. The enemy establishes
itself under our roof and is ready to our hand. By means of insecticides
defence should be relatively easy.
CHAPTER XX
THE GREY LOCUST
I have just witnessed a moving spectacle: the last moult of a locust;
the emergence of the adult from its larval envelope. It was magnificent.
I am speaking of the Grey Locust, the colossus among our acridians,[10]
which is often seen among the vines in September when the grapes are
gathered. By its size--and it grows as long as a man's finger--it lends
itself to observation better than any other of its tribe.
The larva, disgustingly fat, like a rude sketch of the perfect insect,
is commonly of a tender green; but it is sometimes of a bluish green, a
dirty yellow, or a ruddy brown, or even an ashen grey, like the grey of
the adult cricket. The corselet is strongly keeled and indented, and is
sprinkled with fine white spots. As powerful as in the adult insect, the
hind-leg has a corpulent haunch, streaked with red, and a long shin like
a two-edged saw.
The elytra, which in a few days will extend far beyond the tip of the
abdomen, are at present too small triangular wing-like appendages,
touching along their upper edges, and continuing and emphasising the
keel or ridge of the corselet. Their free ends stick up like the gable
of a house. They remind one of the skirts of a coat, the maker of which
has been ludicrously stingy with the cloth, as they merely cover the
creature's nakedness at the small of the back. Underneath there are two
narrow appendages, the germs of the wings, which are even smaller than
the elytra. The sumptuous, elegant sails of to-morrow are now mere rags,
so miserly in their dimensions as to be absolutely grotesque. What will
emerge from these miserable coverings? A miracle of grace and amplitude.
Let us observe the whole process in detail. Feeling itself ripe for
transformation, the insect climbs up the wire-gauze cover by means of
its hinder and intermediate limbs. The fore-limbs are folded and crossed
on the breast, and are not employed in supporting the insect, which
hangs in a reversed position, the back downwards. The triangular
winglets, the sheaths of the elytra, open along their line of juncture
and separate laterally; the two narrow blades, which contain the wings,
rise in the centre of the interval and slightly diverge. The proper
position for the process of moulting has now been assumed and the proper
stability assured.
The first thing to do is to burst the old skin. Behind the corselet,
under the pointed roof of the prothorax, a series of pulsations is
produced by alternate inflation and deflation. A similar state of
affairs is visible in front of the neck, and probably under the entire
surface of the yielding carapace. The fineness of the membrane at the
articulations enables us to perceive it at these unarmoured points, but
the cuirass of the corselet conceals it in the central portion.
At these points the circulatory reserves of the insect are pulsing in
tidal onsets. Their gradual increase is betrayed by pulsations like
those of a hydraulic ram. Distended by this rush of humours, by this
injection in which the organism concentrates all its forces, the outer
skin finally splits along the line of least resistance which the subtle
previsions of life have prepared. The fissure extends the whole length
of the corselet, opening precisely along the ridge of the keel, as
though the two symmetrical halves had been soldered together.
Unbreakable elsewhere, the envelope has yielded at this median point,
which had remained weaker than the rest of the sheath. The fissure runs
back a little way until it reaches a point between the attachments of
the wings; on the head it runs forward as far as the base of the
antennæ, when it sends a short ramification right and left.
Through this breach the back is seen; quite soft, and very pale, with
scarcely a tinge of grey. Slowly it curves upwards and becomes more and
more strongly hunched; at last it is free.
The head follows, withdrawing itself from its mask, which remains in
place, intact in the smallest detail, but looking very strange with its
great unseeing glassy eyes. The sheaths of the antennæ, without a
wrinkle, without the least derangement, and in their natural place, hang
over this dead, translucid face.
In emerging from their narrow sheaths, which clasped them so tightly and
precisely, the thread-like antennæ have evidently met with no
resistance, or the sheaths would have been turned inside out, or
crumpled out of shape, or wrinkled at least. Without harming the jointed
or knotted covers, the contents, of equal volume and equally knotty,
have slipped out as easily as though they were smooth, slippery objects
sliding out of a loose sheath. The method of extraction is still more
astonishing in the case of the hind-legs.
It is now, however, the turn of the front and intermediate pairs of
legs. They pull out of their gauntlets and leggings without the least
hitch; nothing is torn, nothing buckled; the outer skin is not even
crumpled, and all the tissues remain in their natural position. The
insect is now hanging from the dome of the cover solely by the claws of
the long hind-legs. It hangs in an almost vertical position, the head
downwards, swinging like a pendulum if I touch the cover. Four tiny,
steely claws are its only support. If they gave or unclasped themselves
the insect would be lost, as it is as yet unable to unfurl its enormous
wings; but even had the wings emerged they could not grip the air in
time to save the creature from the consequences of a fall. But the four
claws hold fast; life, before withdrawing from them, left them rigidly
contracted, so that they should support without yielding the struggles
and withdrawals to follow.
Now the wing-covers and wings emerge. These are four narrow strips,
vaguely seamed and furrowed, like strings of rolled tissue-paper. They
are barely a quarter of their final length.
They are so soft that they bend under their own weight, and hang down
the creature's sides in the reverse of their normal position. The free
extremities, which normally point backwards, are now pointing towards
the cricket's head as it hangs reversed. The organs of future flight are
like four leaves of withered foliage shattered by a terrific rainstorm.
A profound transformation is necessary to bring the wings to their final
perfection. The inner changes are already at work; liquids are
solidifying; albuminous secretions are bringing order out of chaos; but
so far no outward sign betrays what is happening in the mysterious
laboratory of the organism. All seems inert and lifeless.
In the meantime the posterior limbs disengage themselves. The great
haunches become visible, streaked on the inner faces with a pale rose,
which rapidly turns to a vivid crimson. Emergence is easy, the thick and
muscular upper portion of the haunch preparing the way for the narrower
part of the limb.
It is otherwise with the shank. This, in the adult insect, is armed
along its whole length by a double series of stiff, steely spines.
Moreover, the lower extremity is terminated by four strong spurs. The
shank forms a veritable saw, but with two parallel sets of teeth; and it
is so strongly made that it may well be compared, the question of size
apart, to the great saw of a quarry-man.
The shank of the larva has the same structure, so that the object to be
extracted is enclosed in a scabbard as awkwardly shaped as itself. Each
spur is enclosed in a similar spur; each tooth engages in the hollow of
a similar tooth, and the sheath is so closely moulded upon the shank
that a no more intimate contact could be obtained by replacing the
envelope by a layer of varnish applied with a brush.
Nevertheless the tibia, long and narrow as it is, issues from its sheath
without catching or sticking anywhere. If I had not repeatedly seen the
operation I could not believe it possible; for the discarded sheath is
absolutely intact from end to end. Neither the terminal spurs nor the
double rows of spines do the slightest damage to the delicate mould. The
long-toothed saw leaves the delicate sheath unbroken, although a puff of
the breath is enough to tear it; the ferocious spurs slip out of it
without leaving so much as a scratch.
I was far from expecting such a result. Having the spiny weapons of the
legs in mind, I imagined that those limbs would moult in scales and
patches, or that the sheathing would rub off like a dead scarf-skin. How
completely the reality surpassed my anticipations!
From the spurs and spines of the sheath, which is as thin as the finest
gold-beaters' skin, the spurs and spines of the leg, which make it a
most formidable weapon, capable of cutting a piece of soft wood, emerge
without the slightest display of violence, without a hitch of any kind;
and the empty skin remains in place. Still clinging by its claws to the
top of the wire cover, it is untorn, unwrinkled, uncreased. Even the
magnifying-glass fails to show a trace of rough usage. Such as the skin
was before the cricket left it, so it is now. The legging of dead skin
remains in its smallest details the exact replica of the living limb.
If any one asked you to extract a saw from a scabbard exactly moulded
upon the steel, and to conduct the operation without the slightest
degree of tearing or scratching, you would laugh at the flagrant
impossibility of the task. But life makes light of such absurdities; it
has its methods of performing the impossible when such methods are
required. The leg of the locust affords us such an instance.
Hard as it is when once free of its sheath, the serrated tibia would
absolutely refuse to leave the latter, so closely does it fit, unless it
were torn to pieces. Yet the difficulty must be evaded, for it is
indispensable that the sheaths of the legs should remain intact, in
order to afford a firm support until the insect is completely
extricated.
The leg in process of liberation is not the leg with which the locust
makes its leaps; it has not as yet the rigidity which it will soon
acquire. It is soft, and eminently flexible. In those portions which the
progress of the moult exposes to view I see the legs bend under the mere
weight of the suspended insect when I tilt the supporting cover. They
are as flexible as two strips of elastic indiarubber. Yet even now
consolidation is progressing, for in a few minutes the proper rigidity
will be acquired.
Further along the limbs, in the portions which the sheathing still
conceals, the legs are certainly softer still, and in the state of
exquisite plasticity--I had almost said fluidity--which allows them to
pass through narrow passages almost as a liquid flows.
The teeth of the saws are already there, but have nothing of their
imminent rigidity. With the point of a pen-knife I can partially uncover
a leg and extract the spines from their serrated mould. They are germs
of spines; flexible buds which bend under the slightest pressure and
resume their position the moment the pressure is removed.
These needles point backwards as the leg is drawn out of the sheath; but
they re-erect themselves and solidify as they emerge. I am witnessing
not the mere removal of leggings from limbs already clad in finished
armour, but a kind of creation which amazes one by its promptitude.
Very much in the same way, but with far less delicate precision, the
claws of the crayfish, at the period of the moult, withdraw the soft
flesh of their double fingers from their stony sheath.
Finally the long stilt-like legs are free. They are folded gently
against the furrowed thighs, thus to mature undisturbed. The abdomen
begins to emerge. Its fine tunic-like covering splits, and wrinkles, but
still encloses the extremity of the abdomen, which adheres to the
moulted skin for some little time longer. With the exception of this one
point the entire insect is now uncovered.
It hangs head downwards, like a pendulum, supported by the talons of the
now empty leg-cases. During the whole of the lengthy and meticulous
process the four talons have never yielded. The whole operation has been
conducted with the utmost delicacy and prudence.
The insect hangs motionless, held by the tip of the abdomen. The abdomen
is disproportionately distended; swollen, apparently, by the reserve of
organisable humours which the expansion of the wings and wing-covers
will presently employ. Meanwhile the creature rests and recovers from
its exertions. Twenty minutes of waiting elapse.
Then, exerting the muscles of the back, the suspended insect raises
itself and fixes the talons of the anterior limbs in the empty skin
above it. Never did acrobat, hanging by the toes to the bar of a
trapeze, raise himself with so stupendous a display of strength in the
loins. This gymnastic feat accomplished, the rest is easy.
With the purchase thus obtained the insect rises a little and reaches
the wire gauze, the equivalent of the twig which would be chosen for the
site of the transformation in the open fields. It holds to this with the
four anterior limbs. Then the tip of the abdomen is finally liberated,
and suddenly, shaken by the final struggle, the empty skin falls to the
ground.
This fall is interesting, and reminds me of the persistence with which
the empty husk of the Cigale braves the winds of winter, without falling
from its supporting twig. The transfiguration of the locust takes place
very much as does that of the Cigale. How is it then that the acridian
trusts to a hold so easily broken?
The talons of the skin hold firmly so long as the labour of escape
continues, although one would expect it to shake the firmest grip; yet
they yield at the slightest shock when the labour is terminated. There
is evidently a condition of highly unstable equilibrium; showing once
more with what delicate precision the insect escapes from its sheath.
For want of a better term I said "escape." But the word is ill chosen;
for it implies a certain amount of violence, and no violence must be
employed, on account of the instability of equilibrium already
mentioned. If the insect, shaken by a sudden effort, were to lose its
hold, it would be all up with it. It would slowly shrivel on the spot;
or at best its wings, unable to expand, would remain as miserable scraps
of tissue. The locust does not tear itself away from its sheath; it
delicately insinuates itself out of it--I had almost said flows. It is
as though it were expelled by a gentle pressure.
Let us return to the wings and elytra, which have made no apparent
progress since their emergence from their sheaths. They are still mere
stumps, with fine longitudinal seams; almost like little ropes'-ends.
Their expansion, which will occupy more than three hours, is reserved
for the end, when the insect is completely moulted and in its normal
position.
We have just seen the insect turn head uppermost. This reversal causes
the wings and elytra to fall into their natural position. Extremely
flexible, and yielding to their own weight, they had previously drooped
backwards with their free extremities pointing towards the head of the
insect as it hung reversed.
Now, still by reason of their own weight, their position is rectified
and they point in the normal direction. They are no longer curved like
the petals of a flower; they no longer point the wrong way; but they
retain the same miserable aspect.
In its perfect state the wing is like a fan. A radiating bundle of
strong nervures runs through it in the direction of its length and forms
the framework of the fan, which is readily furled and unfurled. The
intervals are crossed by innumerable cross-nervures of slighter
substance, which make of the whole a network of rectangular meshes. The
elytrum, which is heavier and much less extensive, repeats this
structure.
At present nothing of this mesh-work is visible. Nothing can be seen but
a few wrinkles, a few flexuous furrows, which announce that the stumps
are bundles of tissue cunningly folded and reduced to the smallest
possible volume.
The expansion of the wing begins near the shoulder. Where nothing
precise could be distinguished at the outset we soon perceive a
diaphanous surface subdivided into meshes of beautiful precision.
Little by little, with a deliberation that escapes the magnifier, this
area increases its bounds, at the expense of the shapeless bundle at the
end of the wing. In vain I let my eyes rest on the spot where the
expanding network meets the still shapeless bundle; I can distinguish
nothing. But wait a little, and the fine-meshed tissues will appear with
perfect distinctness.
To judge from this first examination, one would guess that an
organisable fluid is rapidly congealing into a network of nervures; one
seems to be watching a process of crystallisation comparable, in its
rapidity, to that of a saturated saline solution as seen through a
microscope. But no; this is not what is actually happening. Life does
not do its work so abruptly.
I detach a half-developed wing and bring it under the powerful eye of
the microscope. This time I am satisfied. On the confines of the
transparent network, where an extension of that network seems to be
gradually weaving itself out of nothing, I can see that the meshes are
really already in existence. I can plainly recognise the longitudinal
nervures, which are already stiff; and I can also see--pale, and without
relief--the transverse nervures. I find them all in the terminal stump,
and am able to spread out a few of its folds under the microscope.
It is obvious that the wing is not a tissue in the process of making,
through which the procreative energy of the vital juices is shooting its
shuttle; it is a tissue already complete. To be perfect it lacks only
expansion and rigidity, just as a piece of lace or linen needs only to
be ironed.
In three hours or more the explanation is complete. The wings and elytra
stand erect over the locust's back like an immense set of sails; at
first colourless, then of a tender green, like the freshly expanded
wings of the Cigale. I am amazed at their expanse when I think of the
miserable stumps from which they have expanded. How did so much material
contrive to occupy so little space?
There is a story of a grain of hemp-seed that contained all the
body-linen of a princess. Here we have something even more astonishing.
The hemp-seed of the story needed long years to germinate, to multiply,
and at last to give the quantity of hemp required for the trousseau of a
princess; but the germ of the locust's wing has expanded to a
magnificent sail in a few short hours.
Slowly the superb erection composed of the four flat fan-like pinions
assumes rigidity and colour. By to-morrow the colour will have attained
the requisite shade. For the first time the wings close fan-wise and lie
down in their places; the elytra bend over at their outer edges, forming
a flange which lies snugly over the flanks. The transformation is
complete. Now the great locust has only to harden its tissues a little
longer and to tan the grey of its costume in the ecstasy of the
sunshine. Let us leave it to its happiness, and return to an earlier
moment.
The four stumps which emerge from their coverings shortly after the
rupture of the corselet along its median line contain, as we have seen,
the wings and elytra with their innumerable nervures. If not perfect,
at least the general plan is complete, with all its innumerable details.
To expand these miserable bundles and convert them into an ample set of
sails it is enough that the organism, acting like a force-pump, should
force into the channels already prepared a stream of humours kept in
reserve for this moment and this purpose, the most laborious of the
whole process. As the capillary channels are prepared in advance a
slight injection of fluid is sufficient to cause expansion.
But what were these four bundles of tissue while still enclosed in their
sheaths? Are the wing-sheaths and the triangular winglets of the larva
the moulds whose folds, wrinkles, and sinuosities form their contents in
their own image, and so weave the network of the future wings and
wing-covers?
Were they really moulds we might for a moment be satisfied. We might
tell ourselves: It is quite a simple matter that the thing moulded
should conform to the cavity of the mould. But the simplicity is only
apparent, for the mould in its turn must somewhere derive the requisite
and inextricable complexity. We need not go so far back; we should only
be in darkness. Let us keep to the observable facts.
I examine with a magnifying-glass one of the triangular coat-tails of a
larva on the point of transformation. I see a bundle of moderately
strong nervures radiating fan-wise. I see other nervures in the
intervals, pale and very fine. Finally, still more delicate, and running
transversely, a number of very short nervures complete the pattern.
Certainly this resembles a rough sketch of the future wing-case; but
how different from the mature structure! The disposition of the
radiating nervures, the skeleton of the structure, is not at all the
same; the network formed by the cross-nervures gives no idea whatever of
the complex final arrangement. The rudimentary is succeeded by the
infinitely complex; the clumsy by the infinitely perfect, and the same
is true of the sheath of the wing and the final condition of its
contents, the perfect wing.
It is perfectly evident, when we have the preparatory as well as the
final condition of the wing before our eyes, that the wing-sheath of the
larva is not a simple mould which elaborates the tissue enclosed in its
own image and fashions the wing after the complexities of its own
cavity.
The future wing is not contained in the sheath as a bundle, which will
astonish us, when expanded, by the extent and extreme complication of
its surface. Or, to speak more exactly, it is there, but in a potential
state. Before becoming an actual thing it is a virtual thing which is
not yet, but is capable of becoming. It is there as the oak is inside
the acorn.
A fine transparent cushion limits the free edge of the embryo wing and
the embryo wing-case. Under a powerful microscope we can perceive
therein a few doubtful lineaments of the future lace-work. This might
well be the factory in which life will shortly set its materials in
movement. Nothing more is visible; nothing that will make us foresee the
prodigious network in which each mesh must have its form and place
predetermined with geometrical exactitude.
In order that the organisable material can shape itself as a sheet of
gauze and describe the inextricable labyrinth of the nervuration, there
must be something better and more wonderful than a mould. There is a
prototypical plan, an ideal pattern, which imposes a precise position
upon each atom of the tissue. Before the material commences to circulate
the configuration is already virtually traced, the courses of the
plastic currents are already mapped out. The stones of our buildings
co-ordinate according to the considered plan of the architect; they form
an ideal assemblage before they exist as a concrete assemblage.
Similarly, the wing of a cricket, that wonderful piece of lace-work
emerging from a tiny sheath, speaks to us of another Architect, the
author of the plans according to which life labours.
The genesis of living creatures offers to our contemplation an infinity
of wonders far greater than this matter of a locust's wing; but in
general they pass unperceived, obscured as they are by the veil of time.
Time, in the deliberation of mysteries, deprives us of the most
astonishing of spectacles except our spirits be endowed with a tenacious
patience. Here by exception the fact is accomplished with a swiftness
that forces the attention.
Whosoever would gain, without wearisome delays, a glimpse of the
inconceivable dexterity with which the forces of life can labour, has
only to consider the great locust of the vineyard. The insect will show
him that which is hidden from our curiosity by extreme deliberation in
the germinating seed, the opening leaf, and the budding flower. We
cannot see the grass grow; but we can watch the growth of the locust's
wings.
Amazement seizes upon us before this sublime phantasmagoria of the grain
of hemp which in a few hours has been transmuted into the finest cloth.
What a mighty artist is Life, shooting her shuttle to weave the wings of
the locust--one of those insignificant insects of whom long ago Pliny
said: _In his tam parcis, ferè nullis, quae vis, quae sapientia, quam
inextricabilis perfectio!_
How truly was the old naturalist inspired! Let us repeat with him: "What
power, what wisdom, what inconceivable perfection in this least of
secrets that the vineyard locust has shown us!"
I have heard that a learned inquirer, for whom life is only a conflict
of physical and chemical forces, does not despair of one day obtaining
artificially organisable matter--_protoplasm_, as the official jargon
has it. If it were in my power I should hasten to satisfy this ambitious
gentleman.
But so be it: you have really prepared protoplasm. By force of
meditation, profound study, minute care, impregnable patience, your
desire is realised: you have extracted from your apparatus an albuminous
slime, easily corruptible and stinking like the devil at the end of a
few days: in short, a nastiness. What are you going to do with it?
Organise something? Will you give it the structure of a living edifice?
Will you inject it with a hypodermic syringe between two impalpable
plates to obtain were it only the wing of a fly?
That is very much what the locust does. It injects its protoplasm
between the two surfaces of an embryo organ, and the material forms a
wing-cover, because it finds as guide the ideal archetype of which I
spoke but now. It is controlled in the labyrinth of its course by a
device anterior to the injection: anterior to the material itself.
This archetype, the co-ordinator of forms; this primordial regulator;
have you got it on the end of your syringe? No! Then throw away your
product. Life will never spring from that chemical filth.
CHAPTER XXI
THE PINE-CHAFER
The orthodox denomination of this insect is _Melolontha fullo_, Lin. It
does not answer, I am very well aware, to be difficult in matters of
nomenclature; make a noise of some sort, affix a Latin termination, and
you will have, as far as euphony goes, the equivalent of many of the
tickets pasted in the entomologist's specimen boxes. The cacophony would
be excusable if the barbarous term signified nothing but the creature
signified; but as a rule this name possesses, hidden in its Greek or
other roots, a certain meaning in which the novice hopes to find
instruction.
The hope is a delusion. The learned term refers to subtleties difficult
to comprehend, and of very indifferent importance. Too often it leads
the student astray, giving him glimpses that have nothing whatever in
common with the truth as we know it from observation. Very often the
errors implied by such names are flagrant; sometimes the allusions are
ridiculous, grotesque, or merely imbecile. So long as they have a decent
sound, how infinitely preferable are locutions in which etymology finds
nothing to dissect! Of such would be the word _fullo_, were it not that
it already has a meaning which immediately occurs to the mind. This
Latin expression means a _fuller_; a person who kneads and presses cloth
under a stream of water, making it flexible and ridding it of the
asperities of weaving. What connection has the subject of this chapter
with the fuller of cloth? I may puzzle my head in vain: no acceptable
reply will occur to me.
The term _fullo_ as applied to an insect is found in Pliny. In one
chapter the great naturalist treats of remedies against jaundice,
fevers, and dropsy. A little of everything enters into this antique
pharmacy: the longest tooth of a black dog; the nose of a mouse wrapped
in a pink cloth; the right eye of a green lizard torn from the living
animal and placed in a bag of kid-skin; the heart of a serpent, cut out
with the left hand; the four articulations of the tail of a scorpion,
including the dart, wrapped tightly in a black cloth, so that for three
days the sick man can see neither the remedy nor him that applies it;
and a number of other extravagances. We may well close the book, alarmed
at the slough of the imbecility whence the art of healing has come down
to us.
In the midst of these imbecilities, the preludes of medicine, we find a
mention of the "fuller." _Tertium qui vocatur fullo, albis guttis,
dissectum utrique lacerto adalligant_, says the text. To treat fevers
divide the fuller beetle in two parts and apply half under the right arm
and half under the left.
[Illustration: THE PINE-CHAFER.
(_Melolontha fullo._)]
Now what did the ancient naturalist mean by the term "fuller beetle"? We
do not precisely know. The qualification _albis guttis_, white spots,
would fit the Pine-chafer well enough, but it is not sufficient to
make us certain. Pliny himself does not seem to have been very certain
of the identity of the remedy. In his time men's eyes had not yet
learned to see the insect world. Insects were too small; they were well
enough for amusing children, who would tie them to the end of a long
thread and make them walk in circles, but they were not worthy of
occupying the attention of a self-respecting man.
Pliny apparently derived the word from the country-folk, always poor
observers and inclined to extravagant denominations. The scholar
accepted the rural locution, the work perhaps of the imagination of
childhood, and applied it at hazard without informing himself more
particularly. The word came down to us embalmed with age; our modern
naturalists have accepted it, and thus one of our handsomest insects has
become the "fuller." The majesty of antiquity has consecrated the
strange appellation.
In spite of all my respect for the antique, I cannot myself accept the
term "fuller," because under the circumstances it is absurd. Common
sense should be considered before the aberrations of nomenclature. Why
not call our subject the Pine-chafer, in reference to the beloved tree,
the paradise of the insect during the two or three weeks of its aerial
life? Nothing could be simpler, or more appropriate, to give the better
reason last.
We have to wander for ages in the night of absurdity before we reach the
radiant light of the truth. All our sciences witness to this fact; even
the science of numbers. Try to add a column of Roman figures; you will
abandon the task, stupefied by the confusion of symbols; and will
recognise what a revolution was made in arithmetic by the discovery of
the zero. Like the egg of Columbus, it was a very little thing, but it
had to be thought of.
While hoping that the future will sink the unfortunate "fuller" in
oblivion, we will use the term "pine chafer" between ourselves. Under
that name no one can possibly mistake the insect in question, which
frequents the pine-tree only.
It has a handsome and dignified appearance, rivalling that of _Oryctes
nasicornis_. Its costume, if it has not the metallic splendour dear to
the Scarabæi, the Buprestes and the rose-beetles, is at least unusually
elegant. A black or chestnut background is thickly sown with
capriciously shaped spots of white velvet; a fashion both modest and
handsome.
The male bears at the end of his short antennæ a kind of plume
consisting of seven large superimposed plates or leaves, which, opening
and closing like the sticks of a fan, betray the emotions that possess
him. At first sight it seems that this magnificent foliage must form a
sense-organ of great perfection, capable of perceiving subtle odours, or
almost inaudible vibrations of the air, or other phenomena to which our
senses fail to respond; but the female warns us that we must not place
too much reliance on such ideas; for although her maternal duties demand
a degree of impressionability at least as great as that of the male, yet
the plumes of her antennæ are extremely meagre, containing only six
narrow leaves.
What then is the use of the enormous fan-like structure of the male
antennæ? The seven-leaved apparatus is for the Pine-chafer what his long
vibrating horns are to the Cerambyx and the panoply of the head to the
Onthophagus and the forked antlers of the mandibles to the Stag-beetle.
Each decks himself after his manner in these nuptial extravagances.
This handsome chafer appears towards the summer solstice, almost
simultaneously with the first Cigales. The punctuality of its appearance
gives it a place in the entomological calendar, which is no less
punctual than that of the seasons. When the longest days come, those
days which seem endless and gild the harvests, it never fails to hasten
to its tree. The fires of St. John, reminiscences of the festivals of
the Sun, which the children light in the village streets, are not more
punctual in their date.
At this season, in the hours of twilight, the Pine-chafer comes every
evening if the weather is fine, to visit the pine-trees in the garden. I
follow its evolutions with my eyes. With a silent flight, not without
spirit, the males especially wheel and wheel about, extending their
great antennary plumes; they go to and fro, to and fro, a procession of
flying shadows upon the pale blue of the sky in which the last light of
day is dying. They settle, take flight again, and once more resume their
busy rounds. What are they doing up there during the fortnight of their
festival?
The answer is evident: they are courting their mates, and they continue
to render their homage until the fall of night. In the morning both
males and females commonly occupy the lower branches. They lie there
isolated, motionless, indifferent to passing events. They do not avoid
the hand about to seize them. Most of them are hanging by their hind
legs and nibbling the pine-needles; they seem to be gently drowsing with
the needles at their mouths. When twilight returns they resume their
frolics.
To watch these frolics in the tops of the trees is hardly possible; let
us try to observe them in captivity. Four pairs are collected in the
morning and placed, with some twigs off the pine-tree, in a spacious;
cage. The sight is hardly worth my attention; deprived of the
possibility of flight, the insects cannot behave as in the open. At most
I see a male from time to time approaching his beloved; he spreads out
the leaves of his antennæ, and agitates them so that they shiver
slightly; he is perhaps informing himself if he is welcome. Thereupon he
puts on his finest airs and exhibits his attainments. It is a useless
display; the female is motionless, as though insensible to these
demonstrations. Captivity has sorrows that are hard to overcome. This
was all that I was able to see. Mating, it appears, must take place
during the later hours of the night, so that I missed the propitious
moment.
One detail in particular interested me. The Pine-chafer emits a musical
note. The female is as gifted as the male. Does the lover make use of
his faculty as a means of seduction and appeal? Does the female answer
the chirp of her _innamorata_ by a similar chirp? That this may be so
under normal conditions, amidst the foliage of the pines, is extremely
probable; but I can make no assertion, as I have never heard anything of
the kind either among the pines or in my laboratory.
The sound is produced by the extremity of the abdomen, which gently
rises and falls, rubbing, as it does so, with its last few segments, the
hinder edge of the wing-covers, which are held firm and motionless.
There is no special equipment on the rubbing surface nor on the surface
rubbed. The magnifying-glass looks in vain for the fine striations
usually found in the musical instruments of the insect world. All is
smooth on either hand. How then is the sound engendered?
Rub the end of the moistened finger on a strip of glass, or a
window-pane, and you will obtain a very audible sound, somewhat
analogous to that emitted by the chafer. Better still, use a scrap of
indiarubber to rub the glass with, and you will reproduce with some
fidelity the sound in question. If the proper rhythm is observed the
imitation is so successful that one might well be deceived by it.
In the musical apparatus of the Pine-chafer the pad of the finger-tip
and the scrap of indiarubber are represented by the soft abdomen of the
insect, and the glass is represented by the blade of the wing-cover,
which forms a thin, rigid plate, easily set in vibration. The
sound-mechanism of the Pine-chafer is thus of the very simplest
description.
INDEX
A
Acorn-Weevil, _see_ Elephant-Beetle
Ameles, _see_ Mantis, the Grey
Anacreon, on the Cigale, 9
Ant, fable of the Cigale and the, 1-16
Devours the Cigale, 9
Robs the Cigale, 8
Arum, Serpent or Putrid, the, attracts and captures insects by means
of its offensive effluvia, 230-2
B
_Balaninus_, _see_ Elephant-Beetle
Bean, ancestry of, 258-9
Bean, _see_ Haricot
Bean-Weevil, _see_ Weevil
Bees, victims of Philanthus, _see_ latter
Bembex, 168, 172
Bolboceras Gallicus, 217-37
Appearance of, 223
Habits and diet, 226-30
Lodging of, 225
_Bruchus pisi_, see Pea-Weevil
_Bruchus lenti_, see Lentil-Weevil
Buprestes, 21
C
_Cacan_, the, 36-9
Capricornis, 21-2
Cerceris, 172, 178
Chrysomela, 151, 172
Cigale, the, 1-67
Burrow of the, 17-30
Deafness of the, 41-3
Diet, 7
Eggs of the, 45-67
Eggs, hatching of, 61-7
Eggs, method of laying, 50-4
Enemies of the, 47-50
Excavation, method of, 23-7
Fable of Ant and, 1-16
Larva of the, 17-30
Larva, habits of, 61-7
Mechanism of sound, 31-4
Pupa, emergence from, 28
Song of the, 2, 6, 31-44
Species of, 31-6
Cigalo e la Fournigo (Provençal poem), 10-16
Cricket, Field, the, 120-9
Eggs of, 120-2
Excavations of, 124-5
Fertility of, 123
Song of, 126-8
Cricket, Italian, the, 130-5
Appearance of, 130
Song of, 131-4
D
Dermestes, victims of arum, 232
Dioscorides on the Cigale, 29
Diptera, 168, 172
Dog, its love of stenches, 233
Scent of the, 220-22
A truffle-hunter, 218-20
E
Elephant-Beetle (Balaninus or Acorn-Weevil), 238-57
Boring acorns, habit of, 240-4
Eggs, method of laying, 245, 254-7
Motives in boring, 246-50
Snout of, 238-9
Emperor Moth, _see_ Great Peacock Moth
_Empusa pauperata_, _see_ Mantis
Eucores, 176
G
Golden Gardener, the, 102-19
Cannibal habits of, 111-19
Courtship of, 103-10
Ferocity of, 101-4, 108-10
Nutriment of, 102-10
Vermin killer, as a, 107
Grandville, illustrates La Fontaine's fables, 2
H
Halictus, 176, 178
Haricot bean, the, 282-9
Haricot-Weevil, the, _see_ Weevil
Heredia, J.-M. de, 287-90
Hydnocystus, a fungus, 228
Hymenoptera, habits of, 137-8, 150, 162, 171-2, 175-6
L
La Fontaine, fable of the Cigale and the Ant, 3
Locust, Grey, the, 300-16
Larva of, 300
Metamorphosis of, 300-9
Wing, formation of, 309-15
M
Mantis, the _Empusa pauperata_, 97
Mantis, the Grey, 96
Mantis, the Praying, 68-101
Cannibalism of, 82-5
Courtship, 79-83
Hunter, as, 68-78
Nest of, 86-101
_Melolontha fullo_, _see_ Pine-chafer
Minotaur, 225
O
Oak Eggar, the, 202-16, 234-7
Experiments as to sense of smell in males, 208-15
Swarming of males during the mating season, 204-15
Odynerus, 150-1, 172
Osmia tricornis, 173, 175
P
Pea, ancestry of the, 258-9
Pea-Weevil, _see_ Weevil
Peacock Moth, the Great, 179-201, 234-7
Appearance of, 179
Experiments as to sense of smell in males, 184-97
Invasion of house by males, 180-1
Swarming of males, 181-3
Peacock Moth, the Lesser, 197-201
Phalangist, the, 225
_Philanthus aviporus_, 150-178
Cocoon of, 168
Diet of, 150-1
Larvæ of, 168
Methods of killing and robbing bees, 151-160
Motives of robbery, 163-78
Nest of, 167
_Philanthus coronatus_, 178
_Philanthus raptor_, 178
Pine-chafer, the, 317-23
Appearance of, 320
Cry of, 322-3
Habits of, 321
Medical qualities of, supposed, 318-19
Name, origin of Latin, 317-18
Pliny, on the Pine-chafer, 318-19
S
Saprinidæ, victims of arum, 233
Sapromyzon, the, 222
Scarabæus, _see_ Golden Scarabæus
Scent in Insects, _see_ Peacock Moth,
Oak Eggar, Bolboceras Gallicus, arum, putrid
Scolia, 171
Sisyphus, legend of, 139
Sisyphus Beetle, the, 136-49
Burrow of, 143
Larva of, 147-9
Mating of, 142-3
Paternal instinct of 142-6
Pellet of, 142-9
T
Tachytus, 172
_Tigno_, nest of Mantis, 99-101
Truffle-Beetle, 222
Truffle-Dog, 218-20
W
Weevil, Acorn, _see_ Elephant-Beetle
Weevil, the Lentil, 291
Weevil, the Haricot, 282-94
Habits of, 291-6
Invasion of, 284
Larvæ, 297-9
Weevil, the Pea, 258-81, 295
Description of, 261
Enemy, its chief, 280-1
Habits, 261-5
(Deductions to be drawn from), 273-4
Larvæ of, 268-71, 275-6
FOOTNOTES:
[Footnote 1: Whether the Cigale is absolutely deaf or not, it is certain
that one Cigale would be able to perceive another's cry. The vibrations
of the male Cigale's cry would cause a resonance, a vibration, in the
body cavities of other male Cigales, and to a lesser extent in the
smaller cavities in the bodies of the females. Other sounds would cause
a slight shock, if loud enough, but not a perceptible vibration May not
this vibration--felt as in a cathedral we feel the vibrations of the
organ-pipes in the bones of the chest and head or on the covers of the
hymn-book in our hands--serve to keep the insects together, and enable
the females to keep within sight of the males? The sight of an insect is
in one sense poor--it consists of a kind of mosaic picture, and for one
insect to distinguish another clearly the distance between them must not
be very great. Certain gregarious birds and fish whose colouring is
protective have a habit of showing their white bellies as they swerve on
changing their direction. These signals help to keep the flock together.
The white scut of the rabbit and of certain deer is a signal for other
deer or rabbits to follow a frightened flock. It is obviously to the
advantage of the Cigale to follow a gregarious habit, if only for
purposes of propagation, for this would be facilitated by the sexes
keeping together, and, deaf or otherwise, the vibrations of its cry
would enable it to do so. It would be easy to show _a priori_ that the
perception of such vibrations must cause the insect pleasure, as they
stimulate a nervous structure attuned to the perception or capable of
the production of certain complex vibrations. The discord of the cry is
caused by the fact that it consists of a number of vibrations of
different pitch. Some would set the contents of the male resonating
cavities in vibration; others would affect the less regular cavities in
the thorax of the female. We might compare the Cigale's cry to a
sheep-bell. That it is felt and not heard explains its loudness and its
grating quality. A Cigale with the resonating cavities destroyed would
possibly be lost. The experiment is worth trying.--[TRANS.]]
[Footnote 2: It is not easy to understand why the Mantis should paralyse
the cricket with terror while the latter will immediately escape when
threatened by other enemies. As many species of Mantis exactly mimic
sticks and leaves when motionless for purposes of defence, is it not
possible that they mimic their surroundings for purposes of offence as
well? It is easy and natural to say that the Mantis presents a
terrifying aspect. It does to us, by association; but how can we say
that it represents anything of the sort to the probably hypnotic or
automatic consciousness of the cricket? What does it really represent,
as seen from below? A twig, terminating in a bud, with two branching
twigs growing from it, and a harmless nondescript fly or butterfly
perched on the back of it. The combination of a familiar sight and a
threatening sound would very plausibly result in cautious immobility. As
for its instantaneous assumption of the pose, to move instantaneously is
the next best thing to not moving at all. It is less likely to startle
than a slow movement. Twigs which have been bent get suddenly released
in the natural course of events; they do not move slowly. The
instantaneous appearance of a twig where no twig was before may possibly
give the victim pause; it may halt out of caution, not out of
terror.--[TRANS.]]
[Footnote 3: The word "butterfly" is here used, as is the French
_papillon_, as a general term for all Lepidoptera; the insect in
question is of course a moth.]
[Footnote 4: Now classified as _Lasiocampa quercus_.--[TRANS.]]
[Footnote 5: _Rabasso_ is the Provençal name for the truffle; hence a
truffle-hunter is known as a _rabassier_.]
[Footnote 6: Since these lines were written I have found it consuming
one of the true tuberaceæ, the _Tuber Requienii_, Tul., of the size of a
cherry.]
[Footnote 7: The difficulty in conceiving this theory lies in the fact
that the waves travel in straight lines. On the other hand, matter in a
state of degradation may expel particles highly energised and of
enormous velocity. Most antennæ are covered with hairs of inconceivable
fineness; others may contain cavities of almost infinite minuteness. Is
it not thinkable that they are able to detect, in the gaseous
atmosphere, floating particles that are not gaseous? This would not
prevent the specialisation of antennæ as mere feelers in some insects
and crustaceans. The difficulty of such a supposition lies in the
fact of discrimination; but if we did not possess a sense of taste or
smell discrimination would seem inconceivable in their case
also.--[TRANS.]]
[Footnote 8: This classification is now superseded; the Pea and Bean
Weevils--_Bruchus pisi_ and _Bruchus lenti_--are classed as Bruchidæ, in
the series of Phytophaga. Most of the other weevils are classed as
Curculionidæ, series Rhyncophora.--[TRANS.]]
[Footnote 9: The Christmas number (_Noël_) of the _Annales politiques
et littéraires: Les Enfants jugés par leurs pères_, 1901.]
[Footnote 10: The American usage is to call acridians grasshoppers and
Locustidæ locusts. The English usage is to call Locustidæ grasshoppers
and acridians locusts. The Biblical locust is an acridian.]
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