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Title: The Ohio Journal of Science
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DECEMBER,
Volume XVI. 1915 Number 2.

The Ohio

Journal of Science

(Continuation of The Ohio Naturalist)

Official Organ of the

OHIO STATE UNIVERSITY SCIENTIFIC SOCIETY

and of the

OHIO ACADEMY OF SCIENCE

COLUMBUS, OHIO

Annual Subscription Price, $2.00 Single Number, 30 Cents

Entered at the Post-Office at Columbus, Ohio, as Second-Class Matter.

THE OHIO JOURNAL OF SCIENCE

PUBLISHED BY THE

Ohio State University Scientific Society

Issued Monthly during the Academic Year,
from November to June (eight numbers).

OFFICIAL ORGAN OF THE OHIO ACADEMY OF SCIENCE

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Editor, JOHN H. SCHAFFNER
Associate Editor, JAMES S. HINE
Associate Editor, FREDERICK W. IVES

EDITORIAL BOARD

J. F. LYMAN Agricultural Chemistry
F. W. IVES Agricultural Engineering
A. G. MCCALL Agronomy
F. L. LANDACRE Anatomy
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CARL B. HARROP Ceramic Engineering
JAS. R. WITHROW Chemistry
F. H. ENO Civil Engineering
MINNA C. DENTON Home Economics
N. W. SCHERER Forestry
C. S. PROSSER Geology
V. H. DAVIS Horticulture
W. A. KNIGHT Industrial Arts
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HORACE JUDD Mechanical Engineering
JONATHAN FORMAN Pathology
F. C. BLAKE Physics
R. J. SEYMOUR Physiology (General)
CLAYTON MCPEEK Physiology (Medical)
E. R. HAYHURST Public Health & Sanitation
J. S. HINE Zoology and Entomology

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THE OHIO JOURNAL OF SCIENCE

PUBLISHED BY THE OHIO STATE UNIVERSITY SCIENTIFIC SOCIETY

VOLUME XVI DECEMBER, 1915 No. 2

TABLE OF CONTENTS

WELLS—A Survey of the Zoocecidia on Species of Hicoria
Caused by Parasites Belonging to the Eriophyidæ and
the Itonididæ (Cecidomyiidæ) 37
WEST—The Geometry of the Translated Normal Curve 60
GIBSON AND COGAN—A Preliminary List of the Jassoidea
of Missouri, with Notes on Species 71
News and Notes 79

A SURVEY OF THE ZOOCECIDIA ON SPECIES OF
HICORIA CAUSED BY PARASITES BELONGING
TO THE ERIOPHYIDÆ AND THE ITONIDIDÆ
(CECIDOMYIIDÆ).[1]

BERTRAM W. WELLS.

This paper is primarily an attempt to present adequate descriptions
of the types of 30 itonid (cecidomyid) and 2 eriophyid (mite) galls,
collected by the writer on hickory leaves. It is believed to contain
sufficient new material to warrant its publication in advance of a
general survey of N. E. United States zoocecidia, of which it will form
a part. The data is based on collections made in Connecticut, Ohio and
Kansas, most of the material however, being taken in Ohio.

In addition, those forms (few in number) previously described which
have not been seen by the author, have been added, so as to give a
character of completeness to the survey of the two groups of galls.

There are three groups of zoocecidia occurring on hickory trees:

1. Galls formed by species of Eriophyes (Fam. Eriophyidæ of
the Acarina or mites), or an allied genus. Only two are known.

2. Galls induced by species of Phylloxera (Aphididæ of the
Hemiptera). Pergande[2] has presented an excellent survey
of these insects accompanied by very satisfactory descriptions
of the cecidia formed by them.

3. Galls caused by species of Caryomyia (Itonididæ of the
Diptera). Possibly other genera may be represented on the
hickories, but according to Felt[3] “most of the hickory leaf
galls are probably made by species of Caryomyia, though
other midges have been reared from these deformities.”

The genus Caryomyia, which undoubtedly occupies an important place in
relation to the majority of the galls described in the present paper,
will be given special consideration. Felt, to whom American cecidology
is heavily indebted for his extensive studies of dipterous cecidozoons,
presents the following description of the genus Caryomyia in the same
citation as that immediately above.

“Allied to Hormomyia, but differing by the thorax not being greatly
produced over the head and by the presence of but 14 antennal
segments. The males may have the flagellate antennal segments binodose
or cylindric and subsessile and invariably with three low, stout
circumfili. The antennal segments of the female are cylindric and with
two circumfili; palpi tri- or quadri-articulate; wings rather broad,
the third vein joining the costa at or near the wing apex; claws
simple, the pulvilli well developed. The ovipositor of the female is
short and with minute lobes apically. The genus appears to be confined
to hickory leaf galls.”

Adult insects not technically known are given the old generic name
“Cecidomyia.”

These galls as well as similar ones on other kinds of plants arise as
the result of some stimulus (the nature of which is still not definitely
known) applied by the very young larva to the growing tissue of the
immature leaf. Nothing has yet been done on the development of the
itonid galls of the hickories, but from studies on very similar types
we have reason to believe that the ontogeny of the itonid forms is
as follows: The egg is probably deposited superficially (for the
ovipositor of the female Caryomyia is short) on the under side of the
leaflet; on the upper side in a few cases.

Hyperplasia or excessive cell proliferation results (probably not
until after the larva has emerged from the egg) forming at first a
saucer-shaped structure, then cup-shaped and finally by the ingrowth
of the edges, the gall becomes a closed structure enveloping the larva
in a chamber. The distal growth, seldom if ever in the hickory forms,
proceeds so far as to obliterate the opening which was so prominent in
the very immature cup-shape stage. Hence in practically all galls of
this type a minute canal or pore can be demonstrated at the distal end.
In Küster’s[4] very serviceable classification of abnormal plant parts,
these fall under his “umwallungen” cecidia, a term very succinctly
describing their mode of development.

Two of the following described galls have been studied histologically
by Cook,[5] _Caryomyia holotricha_ O. S. and _C. tubicola_ O. S.

Concerning the problem of the distribution of the galls on the
different species of hickory, it is still too early to be able to make
any positive assertions. In most of the reports the species of tree has
not been given. It is very well known that certain species of galls are
found on 2 and 3 species of hickory, but whether they are developed on
all indiscriminately is not known. _H. cordiformis_ seems to bear much
fewer species than _H. ovata_ or _H. alba_. In the present list, the
report of the gall upon a particular species of tree does not at all
imply that it does not occur on others.

Having had the opportunity to give attention to gall collecting
in three rather widely separate localities, eastern Connecticut,
southern and northern Ohio and eastern Kansas, some observations on
the geographical distributions of the hickory itonids are here briefly
presented.

It is sometimes stated that the distribution of gall insects is similar
to that of their host plants. In certain cases this does not seem to
be true. In that of my number 32 first found and described by Sears,
no report of this large and striking form has appeared, showing it
to occur east of the Allegheny mountain system, a region in which
_H. ovata_ is abundant. In the cases of my numbers 5, 9, 19 and 31,
all heretofore unreported and possessing prominent distinguishing
characters, it would seem as though they were somewhat restricted in
their distribution, for while comparatively common in Ohio, they are
never seen in Connecticut or Kansas, where equally intensive collecting
was prosecuted. So few are the students of cecidia and so meager
the data in this field, that it is, however, much too early to make
positive assertions in matters of geographic distribution.

The data on the galls presented herewith was compiled for the most
part at the time of collection; the notes and drawings made from fresh
material. For later comparative work, the material was all preserved in
formalin, each collection being assigned to a vial.

The writer has refrained from attaching a specific name to his new
species of cecidia, a practice very common on the part of European
cecidologists. Even though the adult gall has no direct relation to
the adult insect, the fact, nevertheless, remains that the specificity
of the gall owes its origin to the specificity of the physiological
phenomena of the larval insect, and it is this, which in the mind of
the writer, gives pre-eminence to the insect. The adult gall and the
adult insect can be conceived as arising from the same complex, the
larva, the adult insect bearing, however, a more intimate and direct
relation to the original source of events than the gall. In many cases
the adult insects offer characters, making possible the delimitation of
species, with greater exactness, than do the galls. For these reasons
new names of cecidia should only appear with adequate descriptions of
the cecidozoons.

Though the galls almost uniformly occur on the under side of the
leaflet, the drawings have presented them in an inverted position, with
the gall uppermost, this being the position in which the galls would be
examined. In practically all cases there are two sketches of the type,
one showing the exterior aspect of the gall, the other the interior as
seen in a vertical, median section. The figure number is in all cases
the same as the list number.

The writer wishes to express his appreciation of the hospitality of
his friend, J. L. King, who, as assistant entomologist for the Ohio
Experiment Station, shared his field laboratory during some of the time
in which cecidological collecting was being carried on.

Though the writer has seen (with a few exceptions) the types herewith
detailed an amply sufficient number of times to establish them as
types, he does not claim infallibility, for the key he has worked
out to these types. It is hoped, however, that it, together with the
descriptions and illustrations will enable the student of the hickory
galls to become better acquainted with the members of the two groups
treated.

Britton and Brown’s Illustrated Flora Northern U. S. and Canada, (2nd
edition), New York, 1913, has been followed in the matter of plant
nomenclature.

The following two galls whose makers have been named by Felt have
probably not been seen by the writer. Felt’s descriptions are given.
They are not included in the key.

=Caryomyia thompsoni= Felt.
“Globose, thin-walled, long haired, melon-shaped, dia. 2-3 mm.”

See my number 23.

=Caryomyia antennata= Felt.
“Globose, thick-walled, yellowish green or brown. Dia. 4-5 mm.”

This description, as far as it goes, would indicate a similarity to
C. persicoides Beut.

Felt, Jour. Econ. Ent. 4:456. 1911.

KEY.

The itonid group of galls herewith presented can be distinguished with
one exception (No. 33) from the very common Phylloxera galls (Aphididæ)
by the fact that the latter forms which are sufficiently small to be
comparable in size to the itonids are intercalated in the leaf blade,
i. e. the gall extends more or less prominently from both sides of
the leaf. The itonids always give the appearance of an appendicular
structure attached to the leaf.

1. Gall on nut. Caryomyia nucicola. (3)
1. Gall on leaf. 2.
2. An apparent elongate enlargement of vein.
Cecidomyia cynipsea (?) (4).
2. An inrolled leaf edge. (2).
2. Galls arising from intervenal tissue between veins or immediately
adjoining veins; radially symmetric structures with principal axis
more or less perpendicular to leaf blade. 3.
3. Galls double-chambered as seen in vertical median section. 4.
3. Galls single chambered. 7.
4. Galls definitely depressed. (5).
4. Galls small, sub-globular. (6).
4. Galls definitely conic. 5.
5. Elongate gall with rounded base in definite visible socket. (7).
5. Shorter gall attached by pedicel from rounded base not articulating
with definite socket. 6.
6. Proximal chamber of gall, conic. (5).
6. Proximal chamber of gall, depressed. (8).
7. Galls definitely conic; forms having rounded bases, the distal
portion is sufficiently drawn out to place the cecidium under
this class. 8.
7. Galls spheric, sub-spheric or depressed. 15.
7. Galls sub-cylindric, 2½-3 times as long as wide. 22.
7. Galls obconic, i. e., part projecting from leaf is flat topped,
constricted proximally to the pedicel embedded in the leaf. 25.
7. Blister gall, intercalated in the leaflet, projecting on both
sides. Cecidomyia? sp. (33).
8. Small irregular, low, masses of tissue always in axils of principal
veins of leaflet. Eriophyes sp. (1).
8. Galls definite structures projecting prominently from leaf
surface. 9.
9. Conic gall generally with strongly recurved tip appearing as though
lying on side, decumbent. (9).
9. Galls erect or tilted, seldom bent over, however, beyond angle of
45. 10.
10. Gall with flattened sides, pyramid-like. (10).
10. Galls with sides flattened. 11.
11. Proximal half of gall conic, never sub-globular. (11).
11. Proximal half sub-globular. 12.
12. Galls smooth. 13.
12. Galls pubescent. 14.
13. Galls large, 4-7 mm. long. (12).
13. Galls small, 1½-4 mm. long. (13).
14. Trichomes very long coarse. (14).
14. Pubescence short, fine. (15.)
15. Galls attached by proximal pedicel embedded in leaf, as seen in a
median vertical section.
15. Galls attached by structure extending from leaf into base of gall,
which remains on leaf when gall falls. 20.
16. Walls thick, soft. 17.
16. Walls thin, 18.
17. Galls smooth, depressed or with upward flaring walls forming a
saucer or cup-shaped structure distal to the chamber. (16).
17. Gall globular, finely pubescent like that of a peach. (17).
18. Surface perfectly smooth, symmetrically sub-spherical galls. 19.
18. Surface minutely shagreen-roughened, gall asymmetric, one side
prominently extended laterally. (18).
19. Small galls, 2½ mm. dia., nipple expanded and flattened resembling
the end of a bottle. (19).
19. Larger gall, 3-4 mm. dia., nipple short, pointed. (20).
20. Thick-walled, particularly the distal end, covered with heavy
tawny pubescence. (21).
20. Thinner walled, pubescence very short, puberulent. 21.
20. Very smooth. (22).
21. Depressed (not over 3 mm. high) with column extending through
center of chamber. (23).
21. Globular, 4-5 mm. high. (24).
21. Definitely balloon-shape. (25).
22. Base embedded in socket. 23.
22. Base not embedded in socket. 24.
23. Round-conic at tip. Caryomyia tubicola. (26).
23. Tapering to point, horn-like. (27).
24. Small gall, 2-2½ mm. high, with flaring base, attached by minute
pedicel at center. (28).
24. Large gall, 5-6 mm. long, gradually constricted proximally to very
narrow neck at point of attachment. (29).
25. Distal face with fovea containing a central nipple. Leaf not
projecting on side opposite gall. (30).
25. Distal face with fovea, leading into central pore; no central
nipple. Prominent convexity of leaf on side opposite the gall.
(31).
25. Distal face flaring out at edge into radiate bracts; these
sometimes strongly incurved. (32).

ERIOPHYIDÆ.

1. =Eriophyes?= sp. =Cecidium= nov.

Small galls in the axils of the lateral veins of the leaflets. Above
marked by a light colored angular area 1-1½ mm. dia. Below a small mass
of tissue (the gall proper) fills the angle, covered by a fine close
pubescence. Chamber within of small diameter, irregular in shape. The
characteristic mites were definitely observed. They are white in color.
On some leaflets every angle made by the mid-vein branching into the
lateral ones was occupied by a gall. On _H. cordiformis_, in Athens
County, Ohio, August.

Type specimens at Ohio State University.

2. =Eriophyes?= sp.

Leaf edge gall; edge inrolled involving little more than the teeth.
Variable in length from .5-2 cm. or longer, 1 mm.-2 mm. thick. Outer
surface of affected area finely roughened; color of under side of the
leaf. Thompson states that mites live within the fold. His report is
the first one on this gall. Species of hickory on which specimens were
found not determined.

Thompson, Illus. Cat. Am. Ins. Galls. 1915. p. 57, pl. 10, Fig. 260.

ITONIDIDÆ.

3. =Caryomyia nucicola=, O. S.

“Irregular swelling in the husk produced by the reddish
larvæ. Reference to Caryomyia provisional.” Felt. “Contain
thick walled cells. On Carya (Hicoria) alba.” Jarvis.

Osten Sacken, Trans. Am. Ent. Soc. 3:53. 1870.
Felt, Jour. Econ. Ent. 4:457. 1911.
Jarvis, 39th Ann. Rept. Ent. Soc. Ont. 1908. p. 84.

4. =Cecidomyia cynipsea= O. S.

“Rounded, irregular, hard swelling on the under side of the hickory
leaf, on the mid-rib near the base of the leaf about half an inch long.
In July, pale yellowish and contained in several small hollows, minute
whitish larvæ, with breast bone narrowed anteriorly and ending in a
point.” Osten Sacken.

This form is so different from the other itonid galls of the hickory
that the writer is inclined to place it here tentatively. It is very
similar to _Phylloxera caryævenæ_ Fitch, with the exception that the
hyperplasia extends below the leaf, while in the phylloxera gall it is
developed on the upper side. The writer has observed orange colored
larvæ in the aphid galls, but they were not definitely determined to be
itonid.

Since this type of gall has not since been reported as definitely
caused by itonid larvæ, it is barely possible that Osten Sacken
described the empty phylloxera gall above mentioned containing
inquilinous itonid larvæ. The writer found many of these galls deserted
by the aphids in the middle of July and Pergande states that the aphid
nymphs begin to leave the galls in July. At this time, these galls
are a “pale yellow” color as described for the “cynipsea” gall. The
writer’s observations were made in southern Ohio, while Osten Sacken’s
were made in the vicinity of Washington, D. C.

Osten Sacken, Lowe’s Monogr. Dipt. N. Am. Pt. 1. p. 193. 1862.

5. =Cecidomyia= sp.

Leaf, under side, double chambered conic or depressed (Fig. 5a) gall.
The latter condition is perhaps the more usual. In these forms, the
conic tip is sunken in the central fovea, the gall only measuring from
1½-2 mm. vertical diameter. The conic forms are as though the tip was
pulled out destroying the fovea. These often measure 5 mm. in height.
The width of the galls varies from 3-5 mm. Very light green, or when
older yellow to red, surface roughened with low tubercles as seen
with lens. Inner chamber sub-conic with short mucronate tip. Walls
of both chambers thin and smooth, outer wall slightly sticky. Base
of gall flat, arising from a definite pedicel, resting in a cup-like
depression, which is formed in a definite hyperplasia intercalated
in the leaf. Above, this hyperplasia is evident as a raised circular
area, 2½ mm. diameter, in the center of which is a minute light colored
papilla.

Rather common on _H. alba_. Collected in Hocking and Athens counties,
Ohio.

This double-chambered gall cannot be _Caryomyia inanis_ Felt, for it is
neither “globose and small.” The author describes elsewhere a specimen
which fits that description and is very probably produced by the
cecidozoon just mentioned. Absolute certainty, it must be remembered,
can only be obtained by checking the reared adult insects with the
original descriptions.

Sears described this gall from Cedar Point, Ohio, under the name
_C. inanis_.

Sears, Ohio Nat. 15:380, pl. 18, Fig. 18. 1914.

6. =Caryomyia inanis= Felt.

“Globose, thin-walled with a false chamber at the apex. Dia. 2-3 mm.”
Felt.

In my material, the false chamber is large, occupying more than half
of the gall. The gall is slightly balloon-shape, 2½ mm. high. Surface
perfectly smooth. Collected, Hocking County, Ohio, on H. ovata.

Sears in his “Insect Galls of Cedar Point (Ohio) and Vicinity,”
described my number 5 under this species.

Felt, Jour. Econ. Ent. 4:456. 1911.
Felt, Bull. Brooklyn Ent. Soc. 8:99. 1913.

7. =Cecidomyia= sp. =Cecidium= nov.

On leaf, under side, elongate-conic constricted somewhat at base so as
to resemble a miniature lamp chimney. Arises from saucer-like base. 5
mm. in length. Smooth, greenish-yellow to brown. Two chambered, the
larval chamber at the proximal end, sub-spherical with a dia. about
⅓ the length of the gall. The distal false chamber large, the walls
becoming thin apically. The partition separating the chambers is firm
with a minute perforation at its center. Surface of leaf opposite gall
not raised.

Collected in Hocking County, Ohio, on _H. glabra_, July.

Type specimens unaccountably missing. The description is nevertheless
presented inasmuch as both it and the drawing were made from fresh
material in the field.

8. =Cecidomyia= sp. =Cecidium= nov.

On leaf, under side, a gall similar to 7, perhaps a variety of it,
though its prominent and constant differences would indicate a distinct
species. Conic with rounded base and truncate tip, 4-6 mm. high, 3-4
mm. broad in widest part. The wall at the tip thin, splitting into a
fimbriate condition. Attached by a minute central pedicel, no trace of
a saucer-shaped structure developing around the base. Galls greenish
to red and purple tinted. Uniformly being covered with sparsely
distributed short hairs. Interiorly two chambered, the larval chamber
proximal and occupying nearly one-half of the gall. Walls including the
partition comparatively thin. Surface of leaf opposite gall slightly
raised with reddish tint.

Collected in Athens County, Ohio, on _H. alba_, August.

Type specimens at Ohio State University.

9. =Cecidomyia= sp. =Cecidium= nov.

On leaf, under side, elongate conic, asymmetric, the axis lying
horizontal or parallel with the leaf blade plane. The tip is invariably
strongly recurved upward and backward. The side of the proximal part of
the gall lying against the leaf is flattened and rests close against
the leaf and vein; the galls always spring from the side of a vein.
Size variable from 2 mm. in length to 4 mm. this measurement distally
not being made to the tip but merely to that part of the recurved
terminal portion, farthest from the base. The larger specimens measure
1½-2 mm. in width at the proximal end. Light green to nearly white, or
sometimes roseate tinged. Very smooth. Walls thin distally thickening
toward the basal end.

Not uncommon on _H. alba_ in Hocking County, Ohio, July.

Type specimens at Ohio State University.

A gall, somewhat similar and probably a variety of the above was
collected on _H. glabra_, (Fig. 9a.)

Cylindric-conic, sharply bent over against the leaf, attenuate distal
part short, not recurved, 3½ mm. long. Smooth, white like ivory. Wall
rather thick, hard. Base of gall in shallow saucer-like depression
against the vein. Interiorly the distal end is choked with coarse
trichomes.

10. =Cecidomyia= sp. =Cecidium= nov.

Leaf, under side, distal ⅔ of gall dome-shaped with 3-many triangular
sides, the flaring base resting on the proximal, constricted or
saucer-shaped ⅓; 2-3 mm. high, 3-4 mm. wide. Tip attenuate, not sharp
pointed, however. Light green to yellowish green, the tip darker,
reddish to black. Surface smooth under lens. Larval chamber spherical,
surrounded by sclerenchmya layer. This gall is very distinctive no
other forms having the peculiar angular structure which it possesses.
Not abundant.

Collected at Gypsum, Ohio, August, on _H. microcarpa_.

Type specimens at Ohio State University.

11. =Cecidomyia= sp. =Cecidium= nov.

On leaf, under side, rather large conic gall, whose distal ½-⅓
constitutes a very slender apical process. Through this passes the fine
canal leading to the depressed, sub-globular chamber in the proximal
part of the gall. The galls are either erect or more generally tilted
to one side, always arising from one of the larger veins. 5-8 mm. long,
2½-3½ mm. wide at base. Outline of the flaring sessile base generally
angular. Attenuate distal portion turning dark early. Light greenish
yellow to brown when old. Smooth. Walls of chamber thick. A slender
probable variety of this is figured in 11a, pl. I.

Collected in Hocking County, Ohio, on _H. alba_. July.

Type specimens at Ohio State University.

12. =Caryomyia caryæcola= O. S.

On leaf, under side, large galls with globular basal part extending
into a point distally. Shape suggests that of a Prince Rupert’s drop.
4-7 mm. long. Surface very smooth, greenish to reddish tinged. Some
show a definite blue color over the attenuate apical end. Walls of
medium thickness, very firm. Somewhat similar to _C. sanguinolenta_
O. S. but differs from that gall in its larger size and much more
attenuate distal end. Common on different hickories.

Osten Sacken, Lowe’s Mongr. Dip N. Am. Pt. 1, p. 192. 1862.
Felt, Jour. Econ. Ent. 4:456. 1911.

13. =Caryomyia sanguinolenta= O. S.

On leaf, beneath, stoutly conical, varying in size from 1½ mm. to
4 mm. high. Tip erect or often bent to one side. Smooth, green to
purplish-red and finally a brown when old. Attached to smaller veins by
short pedicel, hidden from view, however, by the rounded base of the
gall. Walls medium in thickness, possessing the rather soft texture of
charcoal when dry; brown in color.

This form is often found in enormous numbers on certain trees, bringing
about early disintegration of the affected leaves. The lower leaves are
more heavily infested due to the fact that the insects are apt to reach
these first in their flight from the ground in the spring.

Osten Sacken, Lowe’s Monogr. Dip. N. Am. Pt. 1, p. 192. 1862.
Beutenmuller, Am. Mus. Nat. Hist. Guide Leaflet No. 16, p. 28,
Fig. 59.
Reprint from Am. Mus. Jour. Vol. 4, 1904.

14. =Cecidomyia= sp. =Cecidium= nov.

Leaf, under side, distal half conic-attenuate from the bulbous or
sub-globular proximal half. Covered with long, coarse trichomes, the
longest being half the length of the gall. Trichomes brown. Tip of
gall generally darker than rest. 3-4 mm. high, 2-3 mm. wide. Cavity
sub-spherical somewhat depressed at right angles to axis of gall. Walls
relatively thick, especially the proximal part. Apical canal evident in
median longitudinal section. Gall attached by short and broad pillar of
tissue extending from the leaf into the fleshy base.

Gypsum, Ohio, August, on _H. ovata_.

Type specimens at Ohio State University.

15. =Cecidomyia= sp. =Cecidium= nov.

On leaf, under side, small, conic galls, generally found in pairs
closely appressed to each other but not confluent. Distal attenuate
⅓ rather sharply constricted from the sub-globular ⅔ of the gall and
generally turned to one side. 2 mm. high, 1½-2 mm. broad at base.
Yellowish in color, definitely and constantly pubescent. Interiorly the
lining of the sub-globular larval chamber is deep blue-black in color.
Walls of medium thickness. Comparatively large region of the base
involved in the attachment of the gall.

Collected in Hocking County, Ohio, on _H. alba_, July.

Type specimens at Ohio State University.

16. =Cecidomyia= sp.

On leaf, under side, greatly depressed with central, prominent nipple,
3-5 mm. dia. 1½-2½ mm. thick (vertical dia.) not including nipple.
Light green, smooth. Firm fleshy with central sub-spherical larval
chamber whose wall is differentiated from the surrounding tissue.
Apical canal through nipple evident. This gall first reported and
illustrated by Thompson.

Thompson, Illus. Cat. Am. Ins. Galls. 1915. p. 56, pl. 13, Fig. 228.

A most interesting variant of this form is illustrated in Fig. 16a.
If it were not for the large number of intermediate forms found, this
one would easily be considered distinct. The region of the chamber
surrounded by thick walls has been much reduced, so that only a
circular area about the upper part of the chamber has the thick wall
projecting from it. This new condition results in the formation of a
definite saucer-shaped structure on the distal end of the gall. In
some specimens the structure was no longer saucer-shape, but by the
ingrowth of the edges it was assuming a spherical form, developing
a two-chambered gall. It is natural to suspect that this may have
been the mode of origin of the four-double-chambered galls described
elsewhere in this paper. That, however, is entirely problematic.

17. =Caryomyia periscoides= Beut.

On leaf, underside, generally large, sub-globular galls. Younger
ones appear like older, both often being found on same leaflet, 4-7
mm. diameter. Galls covered with a fine short yellowish to reddish
pubescence, suggesting the texture of peach “bloom.” Walls very thick,
firm fleshy, surrounding the central spherical cavity, pierced,
however, at the distal end by the fine apical canal. Closely sessile
on leaf, generally at side of principal vein. Collected on _H. alba_,
_glabra_ and _ovata_.

From Felt’s short description, _Caryomyia antennata_ Felt, must have
been taken from a similar gall.

Osten Sacken, Lowe’s Mono. Dip. N. Am. Pt. I. p. 193. 1862.
Beutenmuller, Am. Mus. Nat. Hist. Bull. 23:393. 1907.

18. =Cecidomyia= sp.

On leaf, under side, sub-globular (almost uniformly asymmetric in that
one side projects laterally so as to present a parabolic outline,
rather than a semi-circular one). A short definite nipple terminates
the gall. 2-4 mm. diameter. White or light yellow to red. Walls medium
in thickness, of a soft, almost fleshy consistency. Exterior surface
almost uniformly minutely shagreen-roughened when observed with lens.
The constricted base of the gall rests in a shallow saucer-shaped
structure.

This gall was described from Connecticut in citation below on _H.
ovata_. Rather common in Hocking County, Ohio, on _H. microcarpa_.
July, August.

Felt’s “Cecidomyia sp. Globose, irregular, ovate, granulate, a
slight nipple, dia. 2-3 mm.” probably belongs here.
Felt, Jour. Econ. Ent. 4:456. 1911.
Wells, Ohio Nat. 14:291. 1914.

19. =Cecidomyia= sp. =Cecidium= nov.

On leaf, under side, small, smooth, spherical galls, with a peculiar
tip shaped like the end of a bottle, arising abruptly from the globular
gall, 2-2½ mm. diameter. The gall reminds one of a miniature bomb.
Green to yellowish with dark spots over the distal half. Thin-walled.
Attached by a minute obconic pedicel. The pupa in these galls is
suspended in the upper part of the chamber by a thread passing from
each end of the body to the walls of the chamber. The galls drop from
the leaves in late July. Not common.

Collected in Hocking County, Ohio, July, on _H. microcarpa_.

Type specimens at Ohio State University.

20. =Caryomyia caryæ= O. S.

On leaf, under side, sub-spherical gall with more or less prominent
apical nipple. 3-3½ mm. diameter, rarely 4 mm. Light green, turning
brown, smooth. In many, very definite meridian-like striations can be
observed marking the wall. Wall thin, very fragile and dry. Surface of
chamber smooth as though polished. Attached by conic pedicel arising
from fovea in base of gall. This pedicel with its pointed end attached
to the leaf is surrounded by or rests in a cup-like structure. In this
respect the gall differs markedly from No. 22, which it superficially
very much resembles.

Fig. 20a is a large specimen showing the peculiar interlocking base
exceptionally well developed.

Collected from _H. alba_ and _H. ovata_, July and August.

Felt, Jour. Econ. Ent. 4:456. 1911.

21. =Caryomyia holotricha= O. S.

On leaf, under side, large tawny, long-haired galls, distributed singly
(Fig. 21) or massed (Fig. 21a) on the leaflet. When massed they form a
conspicuous brown, hairy structure, suggesting a huge caterpillar. The
isolated galls are sub-globular to round-conic with or without a small
terminal nipple. 3-5 mm. vertical diameter, 3-5 mm. wide. Interiorly
the chamber of the isolated form is depressed, this fact being
associated with that of the thick distal wall. Gall chamber surrounded
by definite sclerenchyma layer. Cortical tissue firm. Attached by
irregular process from leaf extending into base of gall. In the massed
forms, the galls are similar in structure, but are variously shaped,
due to mutual pressure, (Fig. 21b). Compactly attached to the common
central hyperplasia along the vein, which on the upper side of the leaf
is a reddish irregular, low elevation. Some of these masses are as long
as 5 cm., possessing a thickness of 10-15 mm.

Common on various hickories, particularly _H. ovata_.

A gall which may eventually prove to be a different species but which
here is provisionally classed as a variety of _C. holotricha_, was
found in numbers on the leaves of _H. alba_, though it is probably not
restricted to this species of hickory. Instead of an apical nipple,
it has an apical pit, which is choked with the characteristic brown
pubescence of this type of gall. Internally a tuft of coarse brown
trichomes extends inwardly from the distal side of the chamber. The
chamber occupies the proximal one-half to two-thirds of the gall, the
wall over it being uniformly very thick. This type of gall is constant,
being collected repeatedly and examined minutely.

Based on Felt’s brief description, his _Caryomyia thompsoni_ Felt was
taken from this gall or one very similar to it.

Closely allied to the above variety is another form, with internal
tuft of trichomes, in which the apical nipple is present. The layer
of tissue lining the chamber appears very white, due probably to the
character of the tissue beneath the superficial nutritive layer. In
section the thin white chamber wall is very definitely delimited from
the adjoining darker tissues. Many of these conic-sub-spheric galls
were 6 mm. in width. Collected on _H. glabra_. Types of this and the
above variety are at the Ohio State University.

Osten Sacken, Lowe’s Monogr. Dip. N. Am. Pt. I, p. 193. 1862.
Felt, “Hormomyia holotricha” 23rd Rept. Ins. N. Y. 1907. pp. 382, 389.
Felt, “Caryomyia holotricha” Jour. Econ. Ent. 4:456. 1911.

22. =Cecidomyia= sp. =Cecidium= nov.

On leaf, under side, sub-globular with minute apical nipple. Tip of
latter truncate with fine pore in center. 3 mm. high, 2½-3 mm. wide.
Generally wider through one axis. Smooth; light greenish yellow.
Interiorly a more or less prominent nipple projects inward from the
distal end of the chamber, traversed by the apical pore. Toward
maturity the interior wall is reddened. Gall attached by a short,
cylindric pillar, extending from the leaf into the base of the globular
structure. At the end of summer the galls fall from the leaf, leaving
this pedicel on the leaf. Galls when found are apt to occur in large
numbers, as many as 50-60 commonly being found on a single leaflet.

Collected in Hocking County, Ohio, on _H. microcarpa_, July.

Type specimens at Ohio State University.

23. =Cecidomyia= sp. =Cecidium= nov. (?)

Leaf, under side, depressed (door-knob-shape) closely sessile on leaf
attached by a very short stout pedicel. 3-4 mm. wide, 2-2½ mm. high.
Greenish to dull brown, covered with short, thin pubescence or smooth.
Interiorally from both the proximal and distal sides, truncated,
conic processes extend inward, meeting in the center. From the end of
the upper one numerous, very coarse trichomes radiate into the gall
chamber, which are white at first, turning brown. The central tissue
and the walls are of a firm, fleshy character. There is commonly a more
or less definite fovea, exteriorly at the distal end.

Collected in southern (Hocking County) and northern (Lake County) Ohio
on _H. ovata_.

Thompson briefly describes and illustrates a gall similar to the above
which Felt as editor called _Caryomia thomsoni_. The illustration,
however, shows the gall not be to Felt’s _C. thompsoni_ as he has
described it, viz., “Globose, with long, erect, reddish, fuscous hairs.”

Felt, Bull. Brooklyn Ent. Soc. 8:99. 1913.
Thompson, Illus. Cat. Am. Ins. Galls, p. 56, pl. 12, Fig. 227.

24. =Cecidomyia= sp. =Caryomyia similis= Felt (?)

On leaf, under side, large, globular, 4-5 mm. dia. Light yellow-green
to brown, surface puberulent. A minute nipple terminates the gall.
Walls thin. Attached by a short pillar, over which the basal part of
the sphere fits like a cap. Surface of leaf not noticeably raised on
side opposite the gall.

Collected on _H. microcarpa_ in Ohio and _H. glabra_ in Connecticut.

This gall is very close if not identical with _Caryomyia similis_ Felt.
It differs from his description in that it is not “depressed.”

Felt, Jour. Econ. Ent. 4:456. 1911.
Felt, Bull. Brooklyn Ent. Soc. 8:99. 1913.

25. =Cecidomyia= sp.

On leaf, generally on upper side, balloon-shaped gall, 3-5 mm. high,
3-4 mm. wide. Terminal nipple arising from slight apical depression.
Greenish-brown or sometimes varying toward a very dark purplish tinge,
its peculiar color being very constant and characteristic. The surface
is dotted over with short, swollen glandular hairs. Trichomes sometimes
projecting slightly from apical pore. Walls very thin. Galls attached
to short, stout process of the leaf, to be seen only in median,
vertical section. Surface of leaf on side opposite the gall not raised.
Never numerous on leaflet. Closely related, if not identical, with
_C. caryae_ O. S. See No. 20.

Observed on _H. glabra_, in Hocking County, Ohio, July.

26. =Caryomyia tubicola= O. S.

On leaf, under side, cylindrical with rounded distal end standing
erect from the cup-like base embedded in the leaf blade. 4-6 mm. high,
generally very close to 5 mm. 1 mm. dia. Body of gall, yellow to brown
in color, distal end reddish to brown, at length almost black. Basal
cup, greenish yellow to dark purple. Cylindrical part of gall smooth
as though polished. Gall attached to the cup only at its central basal
part. Before the end of summer the tube-like portion breaks away with
its enclosed larva. On the side of the leaf opposite the gall its
position is indicated merely by a dark discoloration. Very common on
different kinds of hickories.

Osten Sacken, Lowe’s Monogr. Dip N. Am. Pt. 1, p. 192, 1862.
Felt, Rept. Ins. N. Y. 1907. pp. 382, 388, pl. 37, Fig. 5.
Felt, “Caryomyia tubicola” Jour. Econ. Ent. 4:456. 1911.

27. =Cecidomyia= sp. =Cecidium= nov.

Leaf, under side, arising from a shallow cup-like structure. Shape of
a slender horn, slightly curved, 5-7 mm. long, 1¼ mm. wide at base.
Light green at base, changing to yellow, the distal ⅔ of the gall a
deep brown. No demonstrable opening at the end. Walls thin. Surface
smooth, under lens minute longitudinal striations evident. Very little
discoloration on the upper side of the leaf to mark the location of the
gall beneath. Resembles _Caryomyia tubicola_ O. S. but is certainly a
different species.

Collected in Hocking County, Ohio, July, on _H. alba_.

Type specimens at Ohio State University.

28. =Cecidomyia= sp. =Cecidium= nov.

On leaf, generally upper side, delicate, small, sub-cylindric galls,
standing erect, 2-2½ mm. high, less than 1 mm. wide, constricted
proximally to the slightly flaring base. Distal end marked off by a
circular ridge, in the center of which is a rounded nipple. This latter
turns dark early. Gall light green, at length turning brown. Arises
from intervenal areas between the smaller veins. On the under side of
the leaf the gall above is indicated by a minute dark area. Attached to
leaf by minute central pedicel.

Collected in Hocking County, Ohio, on _H. alba_ in July.

Type specimens at Ohio State University.

29. =Cecidozoon= (Type undetermined.) =Cecidium= nov.

On leaf, under side, rather large, pouch-like gall (5-6 mm. long)
arising from a principal vein. Shaped like a stout gourd, it is bent
over nearly recumbent against the blade of the leaf. 2-2½ mm. wide. The
proximal end is sharply constricted at the minute point of attachment.
The walls when collected were light brown in color, sparsely covered
with short white hairs. Walls very thin and when dry brittle. Interior
surface smooth. Inconspicuous on the upper side of the leaf, except for
the minute pore next the vein. Two specimens from the same leaflet.

This gall differs so markedly from all the other cecidomyidous galls
of the hickories, that I am not certain just where to place it. They
contained no occupants of any kind.

Collected in Hocking County, Ohio, on _H. glabra_, July.

Type specimens at Ohio State University.

30. =Cecidomyia= sp. =Cecidium= nov.

On leaf, under side, obconic gall resting in firm collar-like base.
Somewhat similar to 31, but differs in definite constant characters to
make it distinct. Proximal end not rounded but definitely conic, distal
broad end with prominent fovea in the center of which arises a well
defined nipple. Dia. across top, 2½ mm., height from leaf surface, 2
mm. Greenish to reddish brown, smooth. No prominence or convexity of
leaf surface opposite the gall, a slight discoloration only marking the
position of the cecidium.

Collected in Hocking County, Ohio, on _H. microcarpa_, July.

Type specimens at Ohio State University.

31. =Cecidomyia= sp. =Cecidium= nov.

On leaf, under side, small, obconic galls which in development appear
to burst through the epidermis, for gall is surrounded by the ragged
collar-like remnant. The rounded proximal end strongly sunken in the
leaf blade which is prominently convex on the opposite side. Distal
end truncate with funnel-like depression leading to the rather large
apical pore. This latter connects the depressed chamber within with the
exterior. Distal broad end 1½ mm. wide. Gall projects from leaf surface
1-1½ mm. Smooth; light greenish-yellow in color. Walls very thick
distally, very thin proximally where it is connected to the leaf at
the central region. On the upper side of the leaf the low, hemispheric
convexity is reddened, particularly toward the periphery. At first it
was thought that this gall might be a juvenile form of _H. tubicola_,
but later observations have shown it to grow no further in length. It
is without doubt distinct and new.

32. =Cecidomyia= sp.

“Leaf-gall on under surface, having the form of a much depressed
inverted cone, attached by its apex, and with the free base surrounded
by a conspicuous fringe. 3-4 mm. high, 4-5 mm. in diameter. Green to
light yellow-green. Huron, July 25. Quite rare and I believe hitherto
unreported.” Sears.

The author has collected this interesting gall at Gypsum, Ohio, in
August. Many of them measured 5 mm., not including the radiate,
bract-like processes borne on the flaring rim of the gall. The galls
bear an evanescent thin disk of tissue on the distal, central region,
which is clear brown in color and bears erect scattered trichomes. The
underlying surface of the gall or the outer convex part is perfectly
smooth. The origin of the apical, brown disk is problematical; from the
material at hand it appeared as if the rim of the gall had developed by
pushing out beneath the original apical tissue. After the disk falls,
only a minute dark spot marks the apex of the gall. The surface of the
under half of the gall, below the flaring, lacerate rim, is more or
less pubescent.

Chamber comparatively large; walls thin.

This very striking gall has thus far only been collected by Mr. Sears
and myself, both times in northern Ohio and occurring on _H. ovata_.

Some specimens, all occurring on the same leaf varied in that they were
not so depressed (almost sub-hemispheric) and had the rim strongly
inturned against the very convex distal half of the gall.

Sears, Ohio Nat. 15:380. 1914.

33. =Cecidomyia?= sp.

On leaf, blister-like, irregularly circular in outline, 2½-3½ mm.
diameter, ½ mm. thick. Extends above and below about equally. Sometimes
a slight central nipple is formed below. Greenish to brownish with
discolored margin.

Collected in Vinton County, Ohio, on _H. cordiformis_.

Probably same as Felt’s “Leaf blister gall, irregular, dull greenish or
black margined with small nipple. Diameter 3mm.”

This type of gall is so different from all the other cecidomyid forms
that it is doubtful if it is a member of that group. It may possibly
be an immature or small Phylloxera gall. The writer found white larvæ
within his specimens, but was unable to determine them as cecidomyid
larvæ. This gall is thus introduced here, provisionally.

Felt, Jour. Econ. Ent. 4:456. 1911.

EXPLANATION OF PLATES I AND II.

PLATE I.

Fig. 1. Mite gall. Eriophyes? sp. × 1⅓.
Fig. 1a. Mite gall. Eriophyes? sp. × 5.
Fig. 2. Mite gall. Eriophyes? sp. × 3.
Fig. 5. Cecidomyia sp. × 4.
Fig. 5a. Cecidomyia sp. Variety. × 4.
Fig. 6. Caryomyia inanis Felt. × 5.
Fig. 7. Cecidomyia sp. New. × 5.
Fig. 8. Cecidomyia sp. New. × 4.
Fig. 9. Cecidomyia sp. New. × 5.
Fig. 9a. Cecidomyia sp. New. Variety. × 5.
Fig. 10. Cecidomyia sp. New. × 5.
Fig. 11. Cecidomyia sp. New. × 1⅓.
Fig. 11a. Cecidomyia sp. New. Variety? × 5.
Fig. 12. Caryomyia caryaecola O. S. × 3.
Fig. 13. Caryomyia sanguinolenta O. S. × 5.
Fig. 14. Cecidomyia sp. New. × 5.
Fig. 15. Cecidomyia sp. New. × 5.
Fig. 16. Cecidomyia sp. × 5.

PLATE II.

Fig. 16a. Cecidomyia sp. Variety, new. × 5.
Fig. 17. Caryomyia persicoides. Beut. × 5.
Fig. 18. Cecidomyia sp. × 4.
Fig. 19. Cecidomyia sp. New. × 4.
Fig. 20. Caryomyia caryae O. S. × 5.
Fig. 20a. Caryomyia caryae. Large specimen. × 5.
Fig. 21. Caryomyia holotricha O. S. Isolated specimen. × 5.
Fig. 21a. Caryomyia holotricha O. S. Aggregate condition × ⅔.
Fig. 21b. Caryomyia holotricha O. S. Bilocular unit of aggregate
form. × 2.
Fig. 22. Cecidomyia sp. New. × 5.
Fig. 23. Cecidomyia sp. Possibly new. × 5.
Fig. 24. Caryomyia similis Felt (?) × 1.
Fig. 25. Cecidomyia sp, Caryomyia caryae O. S. (?) × 5.
Fig. 26. Caryomyia tubicola O. S. × 3.
Fig. 27. Cecidomyia sp. New. × 3.
Fig. 28. Cecidomyia sp. New. × 5.
Fig. 29. Cecidozoon (undetermined). New. × 3.
Fig. 30. Cecidomyia sp. New. × 7.
Fig. 31. Cecidomyia sp. New. × 6.
Fig. 32. Cecidomyia sp. × 5.
Fig. 33. Cecidomyia ? sp. × 5.

[Illustration: OHIO JOURNAL OF SCIENCE.

VOL. XVI. PLATE I.]

[Illustration: OHIO JOURNAL OF SCIENCE.

VOL. XVI, PLATE II.]

[1] Contribution from the Botanical Laboratory of the Ohio State
University, No. 92.

[2] Pergande, T. “North American Phylloxerinae affecting Hicoria and
other Trees.” Proc. Davenport Acad. Sci. 9:185-271, pls. 1-21. 1903.

[3] Felt, E. P. “The Identity of the better known Midge Galls.” Ottawa
Naturalist, Vol. 25, Nos. 11, 12. 1912.

[4] Küster, E. Die Gallen der Pflanzen, Leipzig. 1911.

[5] Cook, Mel T. “Galls and Insects Producing Them.” Ohio Nat.
4:140-141. 1904.

THE GEOMETRY OF THE TRANSLATED NORMAL CURVE.

CARL J. WEST, Ph. D.

=Introduction.= In curve tracing the graphic representation is
constructed from the equation. Due largely to the requirements of
statistics the converse, namely, to find the equation of the curve
when the distribution of points is given, has become of interest. This
problem is very different from the exercises of analytical geometry
in which a given law of distribution of points is to be translated
into algebraic language. For the presence in the statistical data of
accidental irregularities makes it undesirable as well as practically
impossible to obtain a curve passing _through_ the points. Instead, a
curve is “fitted” to the points, that is, a curve is passed _among_ the
points in accordance with some generally accepted principal such as
that of least squares or the agreement of moments.

Aside from the straight line and the parabolas, the curves proposed
by Pearson[6] have found acceptance. In order to derive curves which
can be fitted to widely varying distributions of points, Professor F.
Y. Edgeworth[7] has proposed to modify, to _translate_, the normal
probability curve with unit standard deviation.

1
y = —————— e^(—(t^2/2))
√(2π)

In this article we shall discuss the geometry of the curves which
Edgeworth obtains by this transformation and derive a method for an
approximate solution of the two equations, one of the fourth and the
other of the sixth degree, which arise in the fitting of a curve of
this class.

In order that the final curve may be written in terms of the
co-ordinates x and y the equation of the base or generating normal
probability curve is written:

1
z = —————— e^(—(t^2/2))
√(2π)

where t denotes abscissas and z ordinates.

Let the abscissas of the transformed curve be functions of the
corresponding abscissas of the base curve. Then it may be assumed that
x can be developed in powers of t, and hence we may write on omitting
fourth and higher powers,

x = a(t + κt^2 + λt^3),

where a, κ and λ are constants to be determined in “fitting” the curve.

Since x denotes the value of a measurement and y the frequency of x,
that is, the number of individuals possessing that value of x, the
magnitude of an element of area denotes the number of individuals
between two values of x. Obviously, therefore, if the transformation is
to be of concrete value the magnitude of an element of area must not be
altered, though of course the shape will be changed. Hence

y dx = z dt,
and y = z dt/dx

1 1
= —————— e^(—(t^2/2)) · ——————————————————
√(2π) a(1 + 2κt + 3λt^2)

The formulas of transformation are thus:

x = a(t + κt^2 + λt^3),

1 1
y = —————— e^(—(t^2/2)) · ——————————————————
√(2π) a(1 + 2κt + 3λt^2)

=Maximum and Minimum Points.= Since only curves with one maximum
point or mode are practically useful it is desirable to determine what
values of the constants a, κ and λ give unimodal curves.

We have

dy dy dt
——— = ——— · ———
dx dt dx

1 (3λt^3 + 2κt^2 + (1 + 6λ)t + 2κ)
= —————— e^(—(t^2/2)) · ————————————————————————————————
√(2π) a(1 + 2κt + 3λt^2)

From the vanishing of the numerator of dy/dx there must result either
one or three real modes for each pair of values for λ and κ, that is,
for each translated curve. To determine what values of λ and κ give
uni-modal curves and what tri-modal it is convenient to consider the
plane of λ and κ.

The discriminant of the equation

3λt^3 + 2κt^2 + (1 + 6λ)t + 2κ = 0
is
16κ^4 - κ^2(1 + 66λ + 117λ^2) + 3λ(1 + 6λ)^3 = 0

This fourth degree curve crosses the horizontal or λ-axis at λ = 0 and
at λ = -⅙ and when λ = 0 its equation reduces to 16κ^4 - κ^2 = 0 or
κ = ±0, κ = ±¼. There is thus contact with the vertical or κ-axis at the
origin and that axis is crossed at the points (0, ±¼). At the point
(λ = -⅙, κ = 0) there is a cusp with the λ-axis for tangent. The other
two intersections with the line λ = -⅙ are imaginary, indicating the
presence of two branches to the curve.

The discriminant of the denominator of dy/dx is the parabola
(in λ and κ),

κ^2 - 3λ = 0

The evident close geometrical connection between the two discriminants
suggests arranging the discriminant of the cubic curve in the following
form:

(κ^2 - 3λ) (16κ^2 - 117λ^2 - 18λ - 1) - 27λ^3(1 - 24λ) = 0

From the equation in this, the well known uv + kws = 0 form, numerous
elementary geometrical facts can be derived. The relations to the
hyperbola, 16κ^2 - 117λ^2 - 18λ - 1 = 0, and to the parabola,
κ^2 - 3λ = 0, premit of the ready plotting of the curve with sufficient
accuracy. The general shape of the curve is shown in Figure 1.

It is to be noted that one branch of the curve is within the parabola,
almost coinciding with it, while the other crosses it at λ = 1/24. From
the original form of this equation it appears that the two branches
of this discriminant meet just inside the parabola in the end points
with approximate co-ordinates (0.043, ±0.360). The geometry of the cusp
and end-points on the discriminant curve is suggestive of interesting
development in detail.

Values of λ and κ for points on the discriminant give curves with two
modes coinciding. All points on one side of the discriminant have three
real and distinct modes, and all on the other have one real and two
imaginary modes. To determine on which side the points giving three
real modes lie we examine a point inside the discriminant. When κ = 0
the modal equation becomes

3λt^3 + (1 + 6λ)t = 0.

______________
Hence the roots are t = 0 and t = ±√(-(1 + 6λ)/3λ). The quantity
under the radical is positive for values of λ between 0 and-⅙.
Therefore, all points within the discriminant curve yield
tri-modal curves and all without uni-modal curves.

[Illustration: _The plane of λ and κ_

_Fig. I_

(_The horizontal scale is twice the vertical scale_)]

The infinite values of dy/dx arise from zero values of the quadratic,
1 + 2κt + 3λt^2. The greatest possible number of modes for any one curve
is therefore five, three from the cubic and two from the quadratic.
Since for infinite values of dy/dx the corresponding ordinates are
infinite, it is advisable to study the location of the infinite points
of the curve, rather to the neglect of the idea of maximum values at
such points.

=Infinite Ordinates.= The infinite points on a curve are given by
the values of t satisfying the equation

3λt^2 + 2κt + 1 = 0.

Except under certain limited conditions to be determined later a curve
with infinite ordinates can not be of great statistical value.

The parabola, κ^2-3λ = 0, obtained by equating the discriminant of
this quadratic to zero separates the points on the (λ, κ) plane which
correspond to curves of _no_ infinite points from those corresponding
to curves of _two_ infinite points.

[Illustration: _Types of Curves_]

Therefore, all pairs of values of λ and κ within the parabola, with the
exception of the very narrow region also within the first discriminant
curve, give uni-modal curves without infinite ordinates.

=Types of Curves.= Without entering into detailed proofs we will
now investigate the general shape of the curves corresponding to values
of λ and κ in each of the distinct regions of the plane of λ and κ.

In the region beneath the parabola and to the right from the shaded
area of Fig. I the curve is essentially of the shape shown in Fig. II.
This type includes the most common skew curves and hence is of great
importance in statistics.

As the point (λ, κ) moves from the λ-axis the crest rises until
the parabola is reached when the infinite ordinates appear as two
coincident lines, shown in Fig. III.

After the parabola is passed, the infinite ordinates separate and the
curve apparently separates into three branches as in Fig. IV.

In crossing the κ-axis to the left one asymptote moves off to infinity
giving a curve of the type shown in Fig. V.

Then the asymptote reappears giving a curve of the type shown in Fig.
VI.

This general shape is preserved as the point moves toward the λ-axis
and when the point reaches the discriminant curve the middle branch is
flattened at the minimum point.

For points within the discriminant curve two minimum points appear and
the central branch now shows a maximum with a minimum point on either
side as in Fig. VII.

=The Tri-modal Curves.= The curves corresponding to values of (λ,
κ) within the discriminant, because of the requirement that an element
of area under the translated curve must always be equivalent to the
corresponding element under the base or generating curve, can be of
statistical value only under the following conditions.

The area between the two ordinates corresponding to t = ±3 is 0.99998
of the total area under the curve, so that when neither of the minimum
points corresponds to points closer than three units to the origin
of the base curve the curve may be practically valuable. A moment’s
consideration will show that the abscissas of the two minimum points
must be practically the same as that of the corresponding infinite
ordinates. The roots of the quadratic

3λt^2 + 2κt + 1 = 0

are numerically greater than 3 for all pairs of values of (λ, κ) lying
above the line

27λ - 6κ + 1 = 0

As statistically promising within the discriminant of the cubic we then
have the shaded area of the (λ, κ) plane.

=The Origin.= The generating curve is the symmetrical normal
probability curve with origin at its center. Since x = 0 when t = 0,
the origin of the translated curve coincides with that of the base or
generating curve. The translated curve may not be symmetrical so that
the mean ordinate may not coincide with the modal ordinate. Because of
the relation between corresponding areas the ordinate at the origin
must continue to divide the area under the curve into equal parts, that
is, the origin and median always coincide.

=Determination of the Constants.= Since the exact position of
the median can not ordinarily be determined by inspection or direct
computation there are in reality four constants to be determined: the
distance between the median and the mean, a, κ and λ.

In determining the constants it is usual to compute the value of the
first four moments. The third and fourth moments are extensions of
the idea of the well known formulas for the first and second moments.
Denoting the moments about the median by μ, we have

1 ⌠+∞
μ_{1}^´ = ——— │ xy dx
N ⌡-∞

1 ⌠+∞
μ_{2}^´ = ——— │ x^{2}y dx
N ⌡-∞

1 ⌠+∞
μ_{3}^´ = ——— │ x^{3}y dx
N ⌡-∞

1 ⌠+∞
μ_{4}^´ = ——— │ x^{4}y dx
N ⌡-∞

where N is the total area under the curve.

The values of the μ’s are computed from the data[8] and equated to the
corresponding integrals which of course involve the four constants.
In this way four equations are obtained from which the values of the
constants may be determined. Since it is our present object to discuss
the solution only of these equations, merely the principal results will
be given.

The general form for the moments about the median of the
area under the translated curve is

1 ⌠+∞
μ_{n}^´ = ——— │ x^{n}y dx
N ⌡-∞

1 ⌠+∞ a^n(t + κt^2 + λt^3)^n
= —————— │ ———————————————————————— e^{-t^2/2} a(1 + 2κt + 3λt^2) dt
√(2π)N ⌡-∞ a(1 + 2κt + 3λt^2)

1 ⌠+∞
= —————— │ a^n(t + κt^2 + λt^3)^ne^{-t^2/2} dt.
√(2π)N ⌡-∞

On applying the two well known formulas:

⌠+∞
│ x^{2n + 1}e^{-x^2} dx = 0
⌡-∞

⌠+∞ 2n + 1 ⌠+∞
│ x^{2n + 2}e^{-x^2} dx = —————— │ x^{2n}e^{-x^2} dx,
⌡-∞ 2 ⌡-∞

the determination of μ_1´, μ_2´, μ_3´ and μ_4´ is reduced to a matter
of algebraic detail. Then on transferring to the arithmetic mean as
origin the values of μ_2, μ_3, and μ_4 can be determined in terms
of a, κ and λ. It is most convenient however, to make use of the
quantities β_1 = μ_3^2/μ_2^3 and β_2 = μ_4/μ_2^2 or rather β = β_1/8
and ϵ = (β_2 - 3)/12 and express the constants in terms of these
quantities. It is to be noted that both ϵ and β are zero for a normal
distribution, that is, for λ = κ = 0.

Omitting the detailed reduction[9] which is straightforward and direct,
we have

(1) μ´ = aκ

(2) μ_2 = a^2(1 + 6x + 15x^2 + 2κ^2)

2κ^2(2κ^2 + Q)^2
(3) β = ——————————————————————
(2κ^2 + R)^3

4κ^4 + 4κ^2S + T
(4) ϵ = ——————————————————————
(2κ^2 + R)^2

where the symbols, S, R, Q and T are defined as follows:

S = 1 + 18λ + 90λ^2,
R = 1 + 6λ + 15λ^2,
Q = 1.5 + 18λ + 135/2λ^2,
T = 2λ + 36λ^2 + 270λ^3 + 810λ^4.

Obviously no algebraic solution can be obtained from equations (3) and
(4) for κ and λ in terms of the computed values β and ϵ, and hence a
resort to tables is necessary. The values of β and ϵ for values of κ
from 0 to 0.0335 and of λ from -0.040 to +0.100 have been computed.[10]
The process of determining the constants of the translated normal curve
consists first in computing β and ϵ from the given data, and then in
entering the table and interpolating for the corresponding values of
κ and λ.[11] On substituting these values in (2) the value of a can be
found and thence on multiplying a by κ the position of the median of
the distribution is obtained.

The sign of κ is determined by the sign of the third moment about the
mean μ_3, that is, by the direction of the skewness or asymmetry. For
positive skewness the mean must lie to the right of the median and
hence μ_1´, the first moment about the mean, must be positive which
necessitates a positive sign for κ. Therefore, the sign of κ is the
same as that of the skewness.

To fit a curve to the given data, after the constants have been
determined it is necessary to find, by solving a cubic equation for
each value, the values of t corresponding to the x’s of the respective
classes. The cubic is

aλt^3 + aκt^2 + at - x = 0.

Any of the various methods of approximating to the solution of a cubic
may be used in solving these equations.

The area of each class can now be obtained by computing the
corresponding areas under the standard normal curve from a table of the
probability integral.

=The Method of Interpolation.= The actual fitting of the curve can
now be readily accomplished.[12] The distinctively geometrical operation
is the interpolation for the values of λ and κ for a given pair of
values of β and ϵ.

Within the limits of the table[13] the curves resulting from the
assignment of a constant value to β are practically straight lines,
β = 0 is the λ-axis; β = 1 is a line parallel to the λ-axis.
Hence we may safely assume that the variation from one column
to the next and from one line to the next is linear for
values of β. That is, ordinary first difference interpolation
methods are applicable.

As regards the system of ϵ curves we have for instance ϵ = .128 at (λ
= .050, κ = 0); again, at approximately (.045, .060) and (.40, .085).
We are therefore warranted in assuming the applicability of first
difference methods to interpolation between the ϵ curves.

As an illustration let us find the values of λ and κ for ϵ = 0.112 and
β = 0.044. On inspection of the table it is seen that λ lies between
0.30 and .035 and κ between .090 and .095. When κ = .090, λ = .033 for
ϵ = .112. When κ = .095, λ = .031 for ϵ = .112. For β = .042 and
κ = .090, λ = .033 and for β = .046 and κ = .095, λ = .031, ϵ = .112 in
each case. Hence, to first differences, λ = .032 and κ = .093 for
ϵ = .112 and β = .044. For interpolation in parts of the table showing
more rapid variations appropriate methods will suggest themselves.

Taken geometrically the table represents two distinct systems of
curves, with each curve of one system intersecting all the curves of
the other system. Therefore, a pair of values for λ and κ can always be
found for values of ϵ and β within the range of the table.

Department of Mathematics, Ohio State University.

TABLE OF ϵ AND β.

(ϵ is the first and β the second number of each pair.)

λ
───┬────────────────────────────────────────────
κ │-040 -035 -030 -025 -020 -015 -010 -005 000
───┴────────────────────────────────────────────
000 -061 -056 -050 -043 -035 -027 -019 -010 000
000 000 000 000 000 000 000 000 000

005 -055 -049 -042 -035 -027 -019 -010 000
000 000 000 000 000 000 000 000

010 -055 -049 -042 -035 -027 -018 -010 000
000 000 000 000 000 000 000 001

015 -049 -042 -035 -027 -018 -009 001
001 001 001 001 001 001 001

020 -048 -041 -034 -026 -017 -008 002
001 002 002 002 002 002 002

025 -047 -040 -033 -025 -016 -007 003
002 002 002 003 003 003 003

030 -046 -039 -032 -024 -015 -006 004
003 003 004 004 004 004 004

035 -045 -038 -031 -023 -014 -005 005
004 005 005 005 005 005 006

040 -037 -030 -022 -013 -004 006
006 006 007 007 007 007

045 -036 -028 -020 -011 -002 008
008 008 008 009 009 009

050 -034 -026 -018 -009 -000 010
009 010 010 011 011 011

055 -032 -024 -016 -007 002 012
011 012 012 013 013 013

060 -022 -014 -005 004 014
014 015 015 016 016

065 -020 -012 -003 006 017
016 017 018 018 019

070 -018 -009 000 009 019
019 020 020 021 022

075 -015 -007 002 012 022
022 023 023 024 025

080 -013 -004 005 015 025
025 026 026 027 028

085 -001 008 018 028
029 030 031 032

090 002 011 021 032
032 033 034 036

095 005 015 025 035
036 037 038 039

100 009 018 028 039
039 041 042 044

(ϵ is the first and β the second number of each pair.)

λ
───┬────────────────────────────────────────
κ │ 005 010 015 020 025 030 035 040 045 050
───┴────────────────────────────────────────
000 010 021 033 045 057 071 084 098 113 128
000 000 000 000 000 000 000 000 000 000

005 010 021 033 045 057 071 084 098 113 128
000 000 000 000 000 000 000 000 000 000

010 011 022 033 045 058 071 085 099 113 128
001 001 001 001 001 001 001 001 001 001

015 011 022 034 046 058 071 085 099 114 129
001 001 001 001 001 001 001 001 001 001

020 012 023 034 046 059 072 086 100 115 130
002 002 002 002 002 002 002 002 002 002

025 013 024 035 047 060 073 087 101 116 131
003 003 003 003 003 003 003 003 003 003

030 014 025 036 049 061 074 088 102 117 132
004 004 004 005 005 005 005 005 005 005

035 015 026 038 050 063 076 089 104 118 133
006 006 006 006 006 006 007 007 007 007

040 017 028 039 052 064 077 091 105 120 135
007 008 008 008 008 008 008 009 009 009

045 019 030 041 053 066 079 093 107 122 137
009 010 010 010 010 011 011 011 011 011

050 021 032 043 055 068 081 095 109 124 139
012 012 012 012 013 013 013 013 014 014

055 023 034 045 057 070 083 097 111 126 141
014 014 015 015 015 016 016 016 016 017

060 025 036 048 060 073 086 100 114 129 144
017 017 017 018 018 019 019 019 019 020

065 028 039 050 062 075 089 102 116 131 146
019 020 020 021 021 022 022 022 023 023

070 030 041 053 065 078 091 105 119 134 149
022 023 024 024 025 026 026 026 026 027

075 033 044 056 068 081 094 108 122 137 152
026 026 027 028 028 029 029 030 030 031

080 036 047 059 071 084 097 111 125 140 155
029 030 031 031 032 033 033 034 034 035

085 039 050 062 075 088 101 115 129 144 159
033 034 034 035 036 037 037 038 039 039

090 043 054 066 079 092 105 119 133 148 163
037 038 039 039 040 041 042 042 043 044

095 046 058 070 083 096 109 123 137 152 167
041 042 043 044 045 046 046 047 048 049

100 050 062 074 087 100 113 127 141 156 171
045 046 047 048 049 050 051 052 053 054

[6] Pearson, Karl:—“Skew Variation in Homogeneous Material;” Phil.
Trans. 1895, Vol. CLXXXVI, A, pp. 253 et seq.

“On the Systematic Fitting of Curves to Observations and Measurements,”
Biometrika, I, pp. 265 et seq. and Biometrika II, pp. 1 et seq.

Elderton:—“Frequency Curves and Correlation,” pp. 1-105; C. & E.
Layton, 1906.

[7] Edgerton, F. Y.:—“On the Representation of Statistics by Means of
Analytical Geometry,” Jour. Roy. Stat. Soc., 1914, Feb., Mar., May,
June and July.

[8] Elderton, 1. c.

[9] Compare Edgeworth, “A Method of Representing Statistics by
Analytical Geometry,” Proceedings Fifth International Congress of
Mathematicians, Cambridge, 1912.

[10] Only a part of the original table appears in the accompanying
table. The original values were computed to four places of decimals,
but three place numbers are sufficient to illustrate the method of
approximating to the solution.

[11] Compare “Tables for Statisticians and Biometricians,” Cambridge
University Press, 1914.

[12] For the statistical details see Elderton, 1. c.

[13] As may be seen on examining the Table.

A PRELIMINARY LIST OF THE JASSOIDEA OF MISSOURI
WITH NOTES ON SPECIES.

By EDMUND H. GIBSON and ERIC S. COGAN,
U. S. Bureau of Entomology.

The following preliminary list of the Jassoidae of Missouri is mainly
the result of collections and notes made by the authors during the
summer months of 1915. On account of the lack of records for this
state the authors were prompted to undertake such a survey. As far
as possible collections were made so as to embrace all conditions in
different sections, giving some attention to ecological relations. The
list comprises some 98 species.

BYTHOSCOPIDAE.

=Macropsis apicalis= Osb. & Ball. A few specimens swept from
weeds at Charleston, Mo., during the late summer.

=Bythoscopus distinctus= VanDuzee. Found in great numbers
on willows in northern Missouri.

=Pediopsis viridis= Fitch. Not common. Taken from willows
near drainage canals in southeast Missouri. Somewhat
more numerous in northern part of the state.

=Idiocerus nervatus= VanDuzee. The only species taken from
willows about Chillicothe.

=Idiocerus verticis= Say. Listed by VanDuzee as occurring in
the state.

=Idiocerus crataegi= VanDuzee. Swept from grasses at
Chillicothe.

=Idiocerus snowi= Gill & Baker. Recorded from Lutesville and
Charleston. Feeding on millet and grasses. Nymphs numerous
during August.

=Agallia sanguinolenta= Prov. Most plentiful in southern part
of state. A decided pest of clover and alfalfa. Other food
plants include wheat and several weeds. Adults abroad in fields
all seasons of the year. Abundant in northern Arkansas.

=Agallia constricta= VanDuzee. One of the earliest jassids to
appear in the spring. Most numerous on grains. Attacks wheat,
rye, oats, alfalfa and grass. Abundant in southern counties.

=Agallia uhleri= VanDuzee. Not very numerous. Occurring
principally near swamps along the Mississippi River. Also
collected from clover fields.

=Agallia novella= Say. Rather uncommon. Taken only in
southern half of state. Adults collected from alfalfa and
from weeds growing in marshes and bogs.

=Agallia 4-punctata= Prov. Clover and alfalfa are among its
food plants. Most abundant in southern counties.

=Agallia gillettei= O. & B. Quite rare. A few adults taken
at Charleston.

TETTIGONIDELLIAE.

=Oncometopia undata= Fabr. Occurs throughout the state, but
not abundant. Swept from grass, weeds and a number of shrubs.

=Oncometopia costalis= Fabr. Occasional specimens taken
throughout southern part of state. Also recorded in the
collection of the Experiment Station at Columbia.

=Homalodisca coagulata= Say. Occasional specimens taken from
cotton and cowpeas. Not abundant.

=Aulacizes irrorata= Fabr. Recorded from the collection of the
Experiment Station at Columbia.

=Kolla bifida= Say. Swept from weeds in marshy lands and from
willows and several shrubs. Recorded only in Mississippi County.

=Kolla geometrica= Sign. Not common. Recorded from Springfield
on grass.

=Kolla tripunctata= Fitch. Mentioned in VanDuzee’s Catalogue
of Described Jassoidea of N. A. as occurring in Missouri.

=Tettigoniella gothica= Sign. Only one specimen taken. From
grass at Lutesville, August 13.

=Tettigoniella occatoria= Say. Common in eastern part of state.
Feeds on clover and weeds.

=Tettigoniella hartii= Wood. Quite numerous throughout the
state during the late summer. Captured only from meadows and
grass lands.

=Tettigoniella hieroglyphica= Say. Rather common in all parts
of the state. Known to feed on clover and several weeds.

=Tettigoniella hieroglyphica= Say. var. hieroglyphica Say. One
adult captured from grass at Rolla, September 21,
by Mr. Geo. W. Barber.

=Tettigoniella hieroglyphica= Say. var. uhleri Ball. Rather
common in eastern half of state. Taken from clover and weeds.

=Tettigoniella hieroglyphica= Say. var. confluens Uhler. Taken
with the above variety.

=Diedrocephala coccinea= Forst. Very generally distributed.
Common but not in great numbers. Injurious to many
ornamental plants in the Missouri Botanical Gardens at
St. Louis. Nymphal cast shins observed on leaves of
Magnolia and American Holly. Adults taken from several
kinds of trees near swamps along the Mississippi River.

=Diedrocephala versuta= Say. Very abundant in central and
southern Missouri. Adults first observed in June. All
stages abroad in fields from July to November. Injurious
to cowpeas in Southeast Missouri. Food plants include
alfalfa, clover, sunflower, grasses, and many weeds. Common
on several ornamental plants and shrubs in the Missouri
Botanical Gardens at St. Louis during September.

=Draeculacephala reticulata= Sign. Rather common at Charleston
and Sikeston during July and August and September, on corn,
alfalfa and grasses. Taken at Chillicothe, Sept. 6, Stanberry,
Sept. 7. The last two records extend the distribution of this
jassid to north of the Missouri River, a fact which is interesting
in view of the distribution recorded by Prof. Osborn in
Bull. 108. Bur. of Ent.

=Draeculacephala angulifera= Walker. Quite common on grass at
Charleston.

=Draeculacephala mollipes= Say. Abundant throughout the state.
All stages present from April to November. Of great economic
importance. A decided pest to young grains and grasses. Known to
feed on an innumerable list of plants and shrubs, field crops,
and ornamentals. Adults migrate in large numbers. About the most
common jassid in Missouri.

=Draeculacephala noveboracensis= Fitch. Taken on grass at
Charleston.

=Helochara communis= Fitch. Swept from wheat on many warm,
sunny days during the winter. In July collected from alfalfa.
Recorded only from Mississippi County.

=Gypona 8-lineata= Say. Occurs throughout the state. Has
special liking for shady and damp places. Appears to be
essentially a grass feeder.

=Gypona flavilineata= Fitch. Swept from grass lands at
Chillicothe.

=Gypona cana= Burm. Taken with G. flavilineata.

=Gypona pectoralis= Spangb. Taken with G. flavilineata.

JASSIDAE.

=Xestocephalus pulicarius= VanDuzee. One specimen of this form
taken at an electric light at Charleston, July 28.

=Xestocephalus tesselatus= VanDuzee. Collected from elm
leaves at Charleston. Quite rare.

=Hecalus lineatus= Uhler. Not common. Nymphs more numerous than
adults during August. Swept from rank growing grasses near the
Mississippi River at Hannibal.

=Parabolocratus viridis= Uhler. Recorded from Springfield,
Columbia, Chillicothe, and Charleston. Observed feeding on grass,
sweet clover and sorghum.

=Platymetopius acutus= Say. Only one adult collected. Swept from
weeds near a bog at Charleston, July 28.

=Platymetopius frontalis= VanDuzee. Very common throughout the
state. Attacks clover, alfalfa, and grasses. Also taken from woody
shrubs.

=Deltocephalus nigrifrons= Forbes. Generally distributed in all
sections of the state. Very abundant during October. Known to feed
upon clover, alfalfa, wheat, many grasses including blue grass,
and several weeds. Attracted to lights at night.

=Deltocephalus weedi= VanDuzee. Quite common on weeds along
roadsides and shady places. Collected at Lutesville and
Charleston during the late summer.

=Deltocephalus flavicosta= Stal. Quite abundant during middle
and late summer, principally in southern part of state. Swept
from native grasses and weeds. Occasional specimens taken from
wheat.

=Deltocephalus sayi= Fitch. Recorded from grass lands in North
western parts of state in September. Quite common in blue grass.

=Deltocephalus inimicus= Say. Common in all parts of the state.
All stages taken from May to November. Food plants include wheat,
oats, alfalfa, clover, cowpeas, timothy, blue grass, other native
grasses, and weeds.

=Deltocephalus albidus= Osb. & Ball. Recorded from the
collection of the Experiment Station at Columbia.

=Deltocephalus obtectus= Osb. & Ball. Quite scarce. Recorded
only from Mississippi County. Near swamps.

=Deltocephalus misellus= Ball. Captured but one adult, in a corn
field near Mississippi River at West Quincy.

=Deltocephalus productus= Walker. Rather scarce. Swept from
clover and weeds at Stanberry.

=Deltocephalus debilis= Uhler. Quite common on grasses in rye
and wheat stubble fields about Hannibal and West Quincy.

=Athysanus exitiosus= Uhler. Occurs throughout the state. With
the exception of Draeculacephala mollipes it is the most common
jassid of northwestern Missouri. Adults present at all seasons of
the year. Food plants include wheat, oats, corn, alfalfa, grasses,
and weeds.

=Athysanus bicolor= VanDuzee. Numerous in southern part of
state, especially in low or bottom lands. Feeds upon many weeds,
grasses and alfalfa.

=Athysanus obtutus= VanDuzee. Not common. A few adults taken
from sweeping wheat fields in the early spring. Recorded only
from Mississippi County.

=Athysanus plutonius= Uhler. Rather rare. Occasional specimens
swept from wheat in Scott and Mississippi Counties.

=Athysanus curtisi= Fitch. Only one adult captured sweeping
weeds at Hannibal.

=Eutettix clarivida= VanDuzee. Recorded from Lutesville and
Charleston, from millet and grasses. Nymphs numerous during
August.

=Eutettix osborni= Ball. Collected by Geo. W. Barber at Poplar
Bluff, from White Aster, used in ornamental plantings.

=Eutettix seminuda= Say. Rather numerous but not abundant.
Occurring in all parts of the state. Collected principally from
weeds and woody shrubs near swamps. Also from grape vines.

=Eutettix strobi= Fitch. Only one adult captured. Feeding on a
leaf of a willow tree growing in a swamp.

=Phlepsius apertus= VanDuzee. Very common throughout the state,
especially in the southeast section. Occurs in great numbers on
alfalfa and clover upon which crops they must be considered a
pest. Also recorded from grasses and weeds. Most abundant during
July and August.

=Phlepsius irroratus= Say. Very common and generally distributed
throughout the state. Of economic importance, attacking alfalfa,
clover, cowpeas, corn, wheat, oats, grape, many grasses, and
weeds.

=Phlepsius cinereus= VanDuzee. Recorded only from Mississippi
County. Most numerous in early summer. Often taken at lights.

=Phlepsius pallidus= VanDuzee. Collected at lights during summer
months. Generally distributed but not abundant.

=Phlepsius superbus= Uhler. Not abundant. Occasional specimens
captured in Mississippi County.

=Scaphoideus sanctus= Say. Occasional specimens taken in
southern part of state.

=Scaphoideus productus= Osborn. One adult collected at Rodney,
August 25.

=Scaphoideus scalaris= VanDuzee. Quite common. Recorded from
Springfield and Hannibal. Taken only from weeds.

=Scaphoideus jucundus= Uhler. Occurs on rank weeds and willows.
Only record is from Stanberry.

=Scaphoideus immistus= Say. Swept from woody shrubs and rank
grasses about Charleston.

=Scaphoideus immistus= Say. var. minor Osborn. One adult taken
at Charleston.

=Thamnotettix clitellarius= Say. An occasional adult taken in
sweepings from grasses and weeds in southeast Missouri. Also taken
from grape at Columbia.

=Chlorotettix viridius= VanDuzee. A few adults taken during the
summer from grasses and weeds growing in low and swampy lands.
Recorded from Pattonsburg and Charleston.

=Chlorotettix unicolor= Fitch. Rather common in central and
northern parts of state. Collected from willows growing in
lowlands.

=Chlorotettix tergatus= Fitch. One adult collected at
Charleston, September 2.

=Chlorotettix necopina= VanDuzee. Only record is from Charleston
where adults were swept from weeds growing in marshy places.

=Chlorotettix galbanata= VanDuzee. Quite rare. Occasional
specimens taken from weeds growing along roadsides in Mississippi
County.

=Jassus olitorius= Say. Not common. A few adults taken in
southeast Missouri. Observed them feeding upon alfalfa.

=Balclutha punctatus= Thunbg. Only record of occurrence is from
Pattonsburg.

=Gnathodus impictus= VanDuzee. Not numerous. Observed feeding on
grasses and several weeds at Charleston during May.

=Cicadula 6-notata= Fall. Occurs in all sections of the state,
most abundant in northeast. Known to feed upon wheat, oats, and
grasses. Especially numerous during October.

=Empoasca mali= LeB. One of the most common and probably the
most injurious leafhopper. Feeds on a great variety of plants,
shrubs and trees. A pest of field crops, nursery stock, and
orchards. Especially abundant during the summer of 1915 on alfalfa
and clover. In early spring adults have been observed feeding on
wheat, rye and native grasses. Exhibits great adaptability to
changes of climate and host plants.

=Empoasca smaragdula= Fall. Listed by Gillette as occurring in
the state.

=Empoasca radiata= Gillette. Swept from willows growing in the
Missouri Botanical Gardens at St. Louis.

=Dicraneura abnormis= Walsh. Not common. Few specimens collected
from blue grass and around lights at night at Chillicothe, during
September.

=Typhlocyba illinoiensis= Gillette. Noted feeding on rose leaves
in the Missouri Botanical Gardens at St. Louis.

=Typhlocyba obliqua= Say. Very abundant on many weeds at
Springfield during August.

=Typhlocyba trifasciata= Say. Listed by Gillette as occurring in
the state.

=Typhlocyba tricincta= Fitch. Abundant on several ornamental
bushes in Missouri Botanical Gardens at St. Louis. Adults
exceedingly quick of movement. Also collected at Pattonsburg and
Columbia.

=Typhlocyba comes= Say. Abundant throughout the state. A severe
pest of grapes, especially in southeast Missouri. Feeds on a
number of weeds. Attracted to lights at night in considerable
numbers.

=Typhlocyba comes= Say. var. vitis Harris. Occurring on
ornamental shrubs, including rose, in the Missouri Botanical
Gardens at St. Louis.

=Typhlocyba comes= Say. var. scutelleris Gillette. Very common
on Sycamore in all stages, and frequently causing severe
infestations. Nymphs and adults feed on under side of leaves
resulting in small whitish brown spots. Occurs in all parts of
Missouri.

=Typhlocyba comes= Say. var. basilaris Say. One adult captured
by Geo. W. Barber at Poplar Bluff, September 4, from white aster.

=Typhlocyba comes= Say. var. ziczac Walsh. Collected from rose
bushes in the Missouri Botanical Gardens at St. Louis.

=Typhlocyba vulnerata= Fitch. Rather numerous on several
ornamental shrubs growing in the Missouri Botanical Gardens.
Feeds on under side of leaves.

NEWS AND NOTES.

The Twenty-fifth Annual Meeting of the Ohio Academy of Science was held
at the Ohio State University, at Columbus, on November 26th and 27th.
A special program was given in commemoration of the Quarter Centennial
Anniversary.

* * * * *

The American Association for the Advancement of Science will hold
its Annual Meeting on the Ohio State University Campus, at Columbus,
December 27th, 1915 to January 1st, 1916. A large attendance is
expected and arrangements have been completed to make the meeting one
of unusual interest.

* * * * *

At the November meeting of the Biological Club, the following officers
were elected for the ensuing year: President, Dr. F. H. Krecker of the
Department of Zoology and Entomology; Vice President, Miss Clara G.
Mark, of the Department of Geology; Secretary and Treasurer, Mr. Rollo
C. Baker, of the Department of Anatomy.

* * * * *

The following officers were named by the Ohio State University
Scientific Society for the year: President, F. C. Blake, Department
of Physics; Vice President, Jas. R. Withrow, Department of Chemistry;
Secretary, R. J. Seymour, Department of Physiology; Treasurer, C. J.
West, Department of Mathematics. These officers constitute an executive
committee which will arrange programs for the regular meetings of the
society, the first of which will occur during January.

* * * * *

An interesting event occurring during the recent meeting of the Ohio
Academy of Science was the short talk given by Dr. T. C. Mendenhall
to the New York and San Francisco alumni of the Ohio State University
by means of the trans-continental telephone. Dr. Mendenhall, while
a member of the University faculty, established the first telephone
to be used in central Ohio, a line from his University office to
his residence, and he expressed himself as greatly pleased at the
opportunity accorded him to speak to his former students over a line
extending across the continent.

* * * * *

The Ohio Academy of Science at its November meeting voted to change
the date of its annual session to a time corresponding to the Easter
recess. The exact time of the meeting is to be determined by the
executive committee, the Academy voting to have the next meeting occur
in the spring of 1916.

* * * * *

Established last Spring, the latest honorary society, Phi Sigma, a
student organization open only to students having completed an amount
of biological work equivalent to a minor, has awakened interest in the
universities of other states. Inquiries concerning the possibility of
establishing other chapters at distant institutions have been received
by the parent chapter at Ohio State University and it is probable that
such chapters will be formed during the present year. Phi Sigma hopes
to publish a biological quarterly in the near future.

Dates of Publication:
November Number, Nov. 22, 1915.
December Number, Dec. 20, 1915.

The College Book Store

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Address:
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THE OHIO STATE UNIVERSITY

*** End of this LibraryBlog Digital Book "The Ohio Journal of Science" ***

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