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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

VOLUME XVI, 1915-16

EDITORIAL STAFF

Editor John H. Schaffner

Associate Editor, James S. Hine

Associate Editor, Frederick W. Ives

EDITORIAI, BOARD

J. F. Lyman Agricultural Chemistry V. H. Davis Horticulture

F. W. Ives Agricultural Engineering W. A. Knight Industrial Arts

A. G. McCall Agronomy C. J. West ...Mathematics

F. ly. Landacre Anatomy Horace Judd Mechanical Engineering

J. H. Schaffner Botany Jonathan Forman Pathology

Carl B. Harrop Ceramic Engineering F. C. Blake Physics

Jas. R. WITHROW Chemistry R. J. Seymour Physiology (General)

F. H. End Civil Engineering Clayton McPeek Physiology (Medical)

Minna C. Denton Home P^conomics E-R.Hayhurst. Public Health and Sanitation

N. W. Sherer Forestry J. S. Hine Zoology and Entomology

C. S. Prosser Geology

OHIO STATE UNIVERSITY,
COLUMBUS. OHIO.

INDEX TO AUTHORS.

BoHANNON, R. D 135, 231

CoGAN, E. S 71, 161, 299

Drake, Carl J 326

Earhart, Robt. F 81

Fullmer, E. L 216

Gibson, E. H., and Cogan, E. S 71

Hills, Thos., M 209

horsfall, j. l 354

Krecker, F. H 125

Lamb, G. F 151

Lord, H. C 3

McCall, a. G 101

Melchers, Leo E 105

Napper, Chas. W 155

Price, W. A 356

Reed, Carlos J 336

Rice, Ed. L 109

Schaffner, John H 1, 104, 360

Sears, Paul B 91

Seymour, Raymond J 32

Sheard, Chas. and Morris, C. S 113

Shideler, W. H 329

Smith, Alpheus W 244

Transeau, Edgar N 17

Wells, Bertram W 37, 249

West, Carl J .' 60

Withrow, Jas. R 219

THE

Ohio Journal of Science

PUBLISHED BY THE

Ohio State University Scientific Society

Volume XVI NOVEMBER , 191 5 No. 1

TABLE OF CONTENTS

Introductory 1

Lord — The Making of a Photographic Objective 3

Transeau — Notes on the Zygnemales 17

Organization of the Ohio State University Scientific Society 32

INTRODUCTORY.

Fifteen years ago the Biological Club of the Ohio State
University began publishing The Ohio Naturalist. This
Journal has had a continuous existence and has been an
important medium in advancing the knowledge of the natural
history of the state. A number of years ago the Naturalist
became the official organ of the Ohio Academy of Science and
was thus sent to every member of the Academy. At that time
the Ohio Academy was largely composed of Biologists and
Geologists, but has now widened its scope to include Physicists,
Mathematicians, and others. It was, therefore, thought desirable
by many that the scope of the Naturalist should be enlarged
so as to make it representative of all of the activities of the
Academy. In accordance with this desire, committees were
appointed by the various departments interested and a plan
for future publication was proposed which was finally adopted.

The Ohio State University Scientific Society was thus
organized at the Ohio State University and will take over the
control of the new publication. This Society is to have some-
what the same relationship to The Ohio Journal of Science
as the Biological Club had to the Ohio Naturalist. The

2 The Ohio Journal of Science [Vol. XVI, No. 1,

management of the Journal is under an Editorial Board made
up of representatives of various scientific departments of the
University. This Board elects annually the Editor and two
Associate Editors.

Editorial Board.

Agricultural Chemistry, J. F. Lyman; Agricultural Engi-
neering, F. W. Ives; Agronomy, A. G. McCall; Anatomy,
F. L. Landacre; Botany, J. H. Schaffner; Ceramic Engineering,
Carl B. Harrop; Chemistry, Jas. R. Withrow; Civil Engineering,
F. H. Eno; Forestry, N. W. Scherer; Geology, C. S. Prosser;
Horticulture, V. H. Davis; Industrial Arts, W. A. Knight;
Mathematics, C. J. West; Mechanical Engineering, Horace
Judd; Pathology, Jonathan Forman; Physics, F. C. Blake;
Physiology (General) R. J. Seymour; Physiology (Medical),
Clayton McPeek; Public Health and Sanitation, E. R. Hay-
hurst; Zoology and Entomology, J. S. Hine.

The Ohio Journal of Science is to be considered as a
continuation of The Ohio Naturalist. It is hoped that with
the wider field covered, it may interest a much larger number
of the scientific people of the state, and be financially supported
so that it may soon develop into a journal of high standard.
It is the intention of the present Editors, with the large field
before them, to publish results of research as well as articles
of general interest in the advancement of Science. On the
natural history side the aim at present will be to pay more
especial attention to the biology, geology and geography of
Ohio, but articles dealing with any other region will be
acceptable.

The Editors for the present year are as follows:
John H. Schaffner — Editor.
James S. Hine — Associate Editor (Business).
Frederick W. Ives — Associate Editor (Subscriptions).

John H. Schaffner.

THE MAKING OF A PHOTOGRAPHIC OBJECTIVE.

Being a Description of a Course in Applied Optics Offered at the Emerson McMillin
Observatory of the Ohio State University.

H. C. Lord.

Photography, in its more serious phase, has taken an
important place in almost every field of human activity while
in its lighter mood, through the development of the "Kodak"
and the roll film, is giving us one of our most delightful pastimes.
As a condition for the best work, a high grade lens is a necessity
and especially so for those extremely short exposures required
in the photography of rapidly moving objects. It often happens
that some of the most perfect and at the same time most
difficult specimens of optical design are found on cameras so
small that they can be easily carried in one's coat pocket.
These so called anastigmats furnish to the optician a difficult
and yet at the same time most fascinating problem for mathe-
matical investigation. Thousands of photographic objectives
are placed on the market every year, yet though almost every
branch of engineering is covered by our technical schools, I
know of no place outside of Germany where a student can be
instructed in the design and construction of a simple photo-
graphic objective. Professor Silvanus P. Thompson in his
inaugural address as President of the British Optical Con-
vention held in London in 1912, states: "In the Universities
and Colleges the only people who are learning Optics are merely
taking it as a part of Physics for the sake of passing an exami-
nation for a degree, and care nothing for the application of
Optics in the industries. They are being taught Optics by
men who are not opticians, who never ground a lens or cal-
culated even an achromatic doublet, who never worked an
opthalmoscope or measured a cylindrical lens." Further on
he speaks as follows: "What is wanted is an establishment
where the whole atmosphere is one of optical interest; where
theory and practice go hand in hand; where the mathematician
will himself grind lenses and measure their performance on the
test bench ; where braincraf t will be married to handcraft ; where
precision, whether in computation or workmanship, will be the
dominating ambition."

4 The Ohio Journal oj Science [Vol. XVI, No. 1,

Some four years before the above quotations were written,
the author started to work up a course in Optics which should
aim, not only to give to the student a knowledge of the funda-
mental theory of lenses, but should also appl}^ those principles
to the methods of optical design and thus enable him to compute
the curves of the component lenses of a photographic objective.
This has now been fairly well worked out and is given in the
Arts college under the official titles "Astronomy, 107, 108, 109
and 110." The basis of this course is "A System of Applied
Optics," by H. Dennis Taylor, the inventor of the Cooke lens.
This splendid volume develops, from the standpoint of geometric
optics, a complete discussion of the formation of an image by a
combination of any number of lenses, but does not apply the
methods and formulae there developed to the actual design
of a photographic objective. The writer of this paper was,
therefore, compelled to work out this part of the theory for
himself and, as he had always felt that all mathematics should
ultimately end in arithmetic and that all arithmetic should
ultimately end in doing something, he resolved at the outset
that the course should end in laboratory work in the actual
computation, grinding and polishing of lenses. As to how well
this has succeeded, I will let the illustrations which accompany
this article speak for themselves. Suffice it to say that the
half tone cuts were made from five by seven enlargements from
negatives, one and three quarters by two and one-eighth inches,
taken with a lens designed and built at this observatory and
working at an aperture of F six. A peculiar feature of this lens
is that it is composed of four lenses all cut from the same piece
of crown glass. This lens beautifully illustrates the importance
of adding to the theoretical side of the course, the practical work
in the laboratory in construction and testing as this lens,
though in the main satisfactory, has one serious defect and
a defect which is very instructive in that it shows that at a certain
point in the design, the theory was weak and needed to be
extended and enlarged. It should be stated that this theoretical
investigation is now completed and ready to be put to the test
of practice.

This Observatory possesses a well equipped instrument
shop, which was used for the practical side of this work and it
has seemed to me that a description of how we used the ordinary
tools of a machine shop, of what special appliances we were

Nov., 1915] Making a Photographic Objective 5

compelled to make, and how we finally ground and polished our
lenses would be of general interest. These methods do not
pretend to be the best, nor those actually employed by the
manufacturer, but they do illustrate how a lens can be made
and how a little ingenuity will enable one if he has the standard
tools of a machine shop to carry out almost any kind of
experimental work.

As a preliminary to this, a brief outline of the problem
before the lens designer may be of interest. A simple lens
consists of a piece of glass bounded by either plane or spherical
surfaces as these, except in large reflecting surfaces, are the only
kind that can be made with sufficient accuracy. Such a lens
would have a great many defects or errors and would be unable
to give a sharp image on the photographic plate unless stopped
down to a very small aperture. By changing the radii of the
surfaces, and the thickness of the lens, the designer can vary
these errors, but after all is said and done he can do but little
to improve the single lens. He then combines lenses of difi'erent
forms and of difiierent kinds of glass into a single objective, in
this way making the positive errors of some of the lenses balance
the negative errors of the others, until he arrives at a com-
bination which is more or less perfect according to his skill as a
designer. How this is accomplished is far beyond the limits of
this paper, so I will now proceed to the micchanical side of the
problem.

The first consideration is the glass ; of course it must be what
is known as optical glass and its selection is really part of the
work of the designer. Optical glass is nothing more than a
very perfect kind of glass which has been exquisitely annealed.
You are all familiar with the intense green of window glass when
seen edgewise; a piece of white paper will hardly be changed
in color when seen through twelve inches of a good optical
crown. The best optical glass is not made in this country, but
must be purchased from either Schott & Gen. of Jena or Mantois
of France. The Jena glass has become very celebrated and
most of the lens makers state that their lenses are made out of it
and as a consequence most people think that Jena glass means a
certain kind, while, as a matter of fact, their catalogue for 1909
shows about seventy different varieties. These differ in
optical qualities and chemical composition, and cost from
about a dollar to five dollars a pound, with a few special varieties

6

The Ohio Journal of Science [Vol. XVI, No. 1,

costing as much as fifteen dollars. This glass comes in slabs,
but will be cut by the makers with either a diamond saw or a
sand saw, the purchaser paying for the "saw dust."

The slabs that were used here were 2" x 6" x Y/ and the
first operation was to cut from these round disks a little larger
than the finished lens. This was accomplished in the following
manner and is illustrated in Fig. 1. In the chuck of a drill
speeder on a. Barnes drill press was placed a 34" steel rod which

1 ^

aJ B

r

Fig. 1

Fig. 2

carried at its lower end a copper tube, A, which was steadied at
the bottom by a steel washer, bored to a loose fit to the tube,
and clamped to the glass as shown. Number 40 Carborundum
was used and lubricated with plenty of water. The tube must be
lifted frequently to allow the abrasive to flow to the cutting
edge. This is done so often that it seems almost a continuous
motion of lifting and pressing down again, the tool resting on
the glass hardly more than two or three seconds at a time.
The cutting may be done at such a speed as to allow of a slight
heating. As soon as the tube has cut itself about a sixteenth of
an inch into the glass, the guiding washer may be removed and

Nov., 1915] Making a Photographic Objective 7

the glass will then act as its own guide. A disk about one inch
in diameter and a half of an inch thick could be cut out in a
little over a half of an hour. At B Fig. 1 is shown one of the
uncut slabs and at C and D two that are about used up. Though
working rather slowly this proved quite satisfactory though
wasteful of glass as it cut a rather wide scarf, copper must be
used ; brass was tried but the wear was so great as to render it
almost useless while the copper shows almost none.

As these disks are cut out they are not only cone shaped but
the edges are very rough so that the next operation was to
grind these to smooth and true circular disks. This was done
on a Wells tool grinder shown in Fig. 2, which was slowed way
down by placing a large pulley on the counter shaft. The glass
to be ground was held by cementing it with pitch onto a piece
of brass rod which in turn was held in the drawing collet of the
head A. A special wheel B, made by the Norton people for
grinding the rims of spectacle lenses, was used and the machine
slowed until the wheel would keep wet when running against a
sponge, C, resting in water. The glass disk was in this way
kept dripping and heating entirely prevented. The grinding
was then carried out just as with any other material and the
edge was made beautifully smooth and true in a few minutes.
The beauty of pitch as a cement for holding the glass is that a
slight heating will soften it so that the disk can be shifted to
any position and then a dash of cold water clamps it in place
and at the same time the pitch will slowly yield to the slightest
pressure so that in a few minutes the glass is entirely free from
strain. In manufacturing this sort of work is done with a
diamond and is of course done much more quickly.

The disks were thick enough to make two lenses each so we
sawed them into two as illustrated in Fig. 3. A is an old pol-
ishing head upon which was mounted a pulley at one end and a
copper disk, B, at the other, the disk being held between large
washers. C is a cast iron box fastened to an arm, D, hinged
at E and kept pressed against the copper disk by a cord passing
over two pulleys on the ceiling. This made a most excellent
automatic feed. The glass to be split was fastened to a block of
pine with pitch and the wood held in the iron box, C, with
wedges. Number 40 Carborundum was used with plenty of
water and the glass was cut through faster than a power hack

8

The Ohio Journal of Science [Vol. XVI, No. 1,

saw would cut through steel. The glass should be cut half
way through and then reversed so that the final break will come
in the middle and thus prevent the edges from spawling off.
The chief defect of this machine was the way it scattered emery.
The disks are now ready for the grinding which is done on the
machine on the right of Fig. 3, which consists simply of a
vertical spindle run by a quarter twist belt from the counter
shaft against the wall. The end of this spindle is tapered at

Fig. 3

the upper end to receive the grinding tool or laps, shown on
the table in Fig. 5 which also shows the spindle raised so that
the grinding lap is seen above the tin box, C, which surrounds
the spindle to catch the abrasive that is thrown off in grinding.
The glass is first smoothed down on a flat lap until it is of equal
thickness at all points as measured by a micrometer when it is
ready to be ground to the ])ro])cr curves. For this purpose the
spherical laps, shown in Fig. 5, are turned in the special machine
illustrated in Fig. 4. The compound rest of an old Seller's
lathe was removed and in its place, on the cross slide of the

Nov., 1915] Making a Photographic Objective

9

carriage, was mounted the sphere turning rest. This consists
of a base. A, in which the shde, B, is so mounted that it can be
rotated about the center, C, by turning the milled head, D,
which carries a worm at the opposite end. E is the tool post
with the cutting tool T and L the lap to be turned. A hole
was drilled at C into which was fitted a round piece of steel the
upper end being pointed and then half cut away like a center
reamer. This was used in finding the zero; the rod, pointed

Fig. 4

end up, was placed in the hole at C and the cutting tool adjusted
against the flattened side. The zero position is then deter-
mined by measuring, with an inside micrometer, the distance
from the tool post to a stop placed at the end of the slide B.
By adding to or subtracting from the zero reading of the
micrometer the length of the radius of the grinding lap, the tool
post may be set to the proper position for either a convex or a
concave surface. This, however, is only approximate, for these
laps must be made with the highest possible accuracy. After
sufficient cuts have been taken to give a spherical surface, the
radius is carefully measured with a special spherometer and
the error in the radius corrected by changing the position of the
cutting tool by an amount calculated from the readings of the

10

The Ohio Journal of Science [Vol. XVI, No. 1,

spherometer. This spherometer we were compelled to build as
we could find none of sufficient accuracy on the market and it is
described in a note at the end of this article.

In Fig. 4, R is simply a steady rest made with the large
overhang to allow the slide B to swing under it in turning a
convex surface. Two master laps, male and female, must be
made and carefully ground together. Every effort should be
taken to make these as accurate as possible since upon these

Fig. 5

depends the goodness of our lens. This special tool is easy to
make and leaves nothing to be desired in its operation. Detail
drawings and directions for making it are given in a note at
the end.

We now come to the grinding or lapping of the lenses them-
selves. This is done in a lap turned as above and carefully
fitted to the master laps and which must be trued from time to
time as the work progresses. This lapping of glass is entirely
different from the lapping of metals in that, while in metals the
lap is to be kept almost free from the abrasive, in glass the lap
•must be freely supplied with emery and water or deep scratches
will result. The best way to apply the emery is with a paint
brush; the brush, satviratcd with emery, being held in front of

Nov., 1915] Making a Photographic Objective 11

the lens as it is ground. The lens may be held in the hand or
cemented to a disk of brass having a center hole drilled in the
back in which is placed a pointed piece of steel held in the
hand, the lens being free to rotate about the pointed steel
holder. Of course where the lens has to be ground to a definite
thickness it must be held by hand. Flour of emery was used to
rough grind though coarser grades would have worked faster.
The final smooth grinding was done with a special fine emery
made for this purpose by Bausch and Lomb. Great care must
be taken in the grinding to keep the lens as nearly centered as
possible. A lens is said to be centered when the line which
joins the centers of curvature of the surfaces passes through
the center of figure. Obviously if a double convex lens could be
ground to a knife edge it would be centered but if this were done
the edge would be almost certain to crumble in the final polishing
and deep scratches result. The centering of a convex lens can
be watched by keeping the edge as nearly uniform of thickness
as possible with a concave lens, if the original blank is made
larger than necessary and care is taken to make the sides par-
allel, the centering can be watched by keeping a fiat edge of
equal width around the concave portion, the lens being^ placed
back on the flat tool, from time to time, as the work progresses.
If care is used the lens need be made but little larger than the
finished size to allow for the final accurate centering to be
described later.

After being smooth ground the lens is beautifully smooth
and velvety to the touch but is just as much ground glass as
ever, that is, it is absolutely opaque. We now come to the
polishing. This is done with specially prepared rouge and
only an excessively small amount of glass is taken off. Lord
Rayleigh in a paper on "Polishing of Glass Surfaces" read
before the British Optical Convention held in 1905, states:
"I started with a finely ground surface, rather more finely
ground I think than is used in practice, and I found that in
order to obtain a pretty good polish it was necessary to remove
a weight of glass, corresponding to a depth of about 6 wave-
lengths. I do not pretend that such a polish would satisfy the
requirements of commerce; probably the 6 would have to
be raised to 10 or 12 in order to get to the bottom of the
deepest pits." When it is remembered that a wave length is
about the fifty thousandth part of an inch we realize how very

12 The Ohio Journal of Science [Vol. XVI, No. 1,

delicate such lapping must be. For this work the lap is covered
with pitch which has been brought to the proper degree of
hardness either by boiling, to harden it or by adding asfalt
varnish to soften it. The proper degree of hardness is very
important and must be adjusted to the temperature of the
room. Obviously if the pitch is too soft it will not hold its
shape and it will be impossible to hold the polishing tool to the
proper radius. I have put three different curves on a lens
about an inch in diameter in a few minutes and it had to go
back on the grinding machine before it could be finished.

The polishing tool is prepared as follows: A disk of pitch,
about 3^" thick, is cast by pouring it in a mold made by a
strip of brass bent to a circle, the ends clamped w^th a tool
maker's clamp, and rested on a piece of cold cast iron which
has been planed smooth. This should be of such size that when
bent to the proper shape it can be molded over a tool similar to
the grinding tool but with a radius changed by about the
thickness of the pitch. This tool is then heated and painted
with a stick of pitch, the disk is warmed, and the two pressed
together, when cooled the pitch will stick tight to the iron but
will be far from a smooth surface. This and the master tool of
the opposite curvature are placed in warm water and pressed
together and at the same time one slowly rotated, one about the
other. When a good fit is secured they are cooled and a number
of small holes, about 1-8" in diameter, are drilled all over the
pitch to distribute the abrasive, which of course spoils the sur-
face and the tool must be again pressed. This pressing to shape
must be done repeatedly and requires great care and some
practice in order to have the pitch come to the exact opposite
of the pressing tool. The most important thing is to do the
pressing slowly and in fact in the whole process of this work
one must never get in a hurry. Ritchey, in his memoir on the
construction of the great 60" at Mt. Wilson, recommends cov-
ering the pitch with beeswax, and for quicker and poorer work
a cloth polisher may be used, the cloth being a special felt and
cemented to the cast iron tool with a thin layer of pitch.

The abrasive is rouge or red oxide of iron and its preparation
is fully described in the above mentioned work by Ritchey. We
purchased the anhydrous red oxide of iron from Merck & Co.
This was mixed with plenty of water in the jars shown at E,
Fig. 5. The rouge will rapidly precipitate, the coarse particles

Nov., 1915] Making a Photographic Objective 13.

falling to the bottom, and leaving clear water above the precip-
itated rouge. The upper two-thirds of the rouge will be almost
perfect and will give a beautiful polish when carefully siphoned
off. This should be kept in tightly corked bottles, one of the
best things is a horse radish jar as this has a place for the
handle of the brush in the glass stopper, and all dust and grit
can be easily washed off before the jar is opened. For polishing,
the lens is cemented to a handle at whose end is a piece of brass
turned to fit the lens in the sphere turning machine already
described. Even in a small lens the polishing tool must be run
slowly, the speeds of our machines run from 170 to 300 revolu-
tions per minute ajid the fastest can seldom be used. The
reason of this is that the lens fits the polisher so perfectly that
almost a perfect vacuum is formed and the lens hugs the pol-
ished so closely that it is impossible to hold it in small sizes by
hand alone and in the case of a convex surface, if the cavity is
carried clear out to the edge of the glass disk, this may be broken
simply by the friction due to this grip of the glass and pitch.
Fig. 5 shows a horizontal polishing head at B and a vertical one
at C. There is little choice except that for convex surfaces B
seems the best, as it can be run faster, while for concave C seems
better.

The lenses are now ready to be centered, that is, the circum-
ference so turned that the line which joins the centers of
curvature of the two spherical surfaces shall pass through the
center of figure. In order to accomplish this, the lens is first
cleaned from the pitch used to cement it to the handle used in
holding the lens for polishing. For a long time I could find no
way of doing this satisfactorily when pitch was the cement;
finally, I laid my troubles before Dr. A. M. Bleile, Head of the
Department of Physiology, and he suggested to first soak the
lens in lard and then wash it in benzol (CeHe). This worked
like magic though the first time I tried it I used some lard that
had been heated with some pitch in it which made the lard very
soft in fact almost as soft as it could be and yet not be an oil,
and this same lard was used over and over again. The action
is rather peculiar; the lard does not apparently effect the pitch
at all but after a few minutes in the benzene it all flakes off and
leaves the lens perfectly clean. The actual centering is then
carried out on the grinding machine shown in Fig. 2 ; A holder,
D, whose front face has been turned in the spherical turning

14 The Ohio Journal of Science [Vol. XVI, No. 1,

machine to fit one of the surfaces of the lens, is held in the
head A. If the lens be cemented to this with a thin coat of
pitch, it is obvious that the surface of the lens next to the
holder will have its center of curvature coincide with the axis
of rotation of the spindle of the head A, but the center of
curvature of the other lens surface will probably fall outside
of this axis. A lamp, L, has a tin chimney M'ith a pin hole in it
turned towards the lens, this pin hole forming a brilliant point
of light, an image of which is formed by each surface and
reflected by the total reflecting prism, P, into the telescope, T,
where it is seen through the eyepiece. If the centers of cur-
vature of both surfaces do not accurately coincide with the axis
of rotation of the head. A, the images of the pin hole will
describe circles as this axis is rotated. The back surface will
of course be centered if the layer of the pitch used as cement is
of uniform thickness which will generally be the case if the
work has been carefully done ; but in any case the image formed
by it should be examined. If the front surface is out of center,
as it generally will be, the holder should be warmed and the
lens shifted, care being used to keep it tight against the surface
of the holder as it is being shifted. As soon as both images
remain stationary as the head. A, is rotated, the lens is fed
against the wheel, B, and ground true and to size. This
worked beautifully and the tests were wonderfully sensitive.
As soon as the component lenses of the objective have all been
thus centered, they are ready to be assembled in the cell or
shutter in which they are to be used; but as this is simply a
matter of careful machine work, I need not describe it further.

I know of no literature on the grinding of small lenses though
the following memoirs on the making of large reflecting tel-
escopes should be in the hands of any one interested in this
work :

On the Construction of a Five-foot Equatorial Reflecting Telescope. By A. A.

Common, LL. D., F. R. S. Memoirs of the Roval AstroRomical Society,
Vol. L., lSOO-91.

On the Construction of a Silvered Glass Telescope, Fifteen and a Half Inches in
Aperture, and its Use in Celestial Photography. By Henry Draper, M. D.,
Smilhsonian C'dntrihutions to Knowledj^e, Vol. '-i-i.

On the Modern Reflecting Telescope and the Making and Testing of Optical Mirrors.
By George W. Ritchey. Smithsonian Contributions to Knowledge, Vol. 34.

Nov., 1915] Making a Photographic Objective

15

Note 1 — ^A Spherometer for Short Radii.

In Fig. 6, A is a regular Brown & vSharpe Micrometer Head with the measuring
point ground to an angle of 60° and slightly rounded; B is a round steel base all
machined at one setting in which the micrometer head is clamped by a set screw
not shown.

Oy

Fig. 6

Let r be the radius of the spherical surface, MNO, and we will have at once
r= (a^ + d^) / 2d. The advantage of this form of spherometer is that it is very
easy to make the point of the micrometer exactly central with the base and the
value of 2a can be accurately determined by means of an ordinary micrometer
calliper. For a convex surface, 2a should obviously be the inside diameter of
the base, B.

In using the instrument, two tables, one for concave and one for convex
surfaces, should be prepared; these tables to give the power in dioptres for each
one thousandth of an inch in the value of d. Using the American Optical Co.'s
Standard Index, namely, n ecjual to 1.5000 and one dioptre as being the power of a
lens of 40 inches focus, we have, for a piano lens, p = 40/f = 40d/(a^-|-d2) since
f = r/(M-l).

The advantage of forming the table in dioptres in place of radii directly is
that the tabular differences are small at all parts of the table so that interpolation
can be readily done and this is not the case in tables which give the radii directly.

If upon measuring the radius of the tool or lap being turned in the sphere
turning machine, Fig. 4, with this spherometer, the tool is found to be in error by
an amount Ap this may be corrected by changing the position of the cutting
tool by an amount 20Ap/p^.

16

The Ohio Journal of Science [Vol. XVI, No. 1,

Note 2 — Cross Section of the Sphere Turning Rest.

m m

c

I

J

Fig. 7

In Fig. 7 is .shown a cross section of the sphere turning rest further illustrated
in Fig. 4. In machining this the following suggestions should be followed. The
piece M should be cast with a lug projecting from the face PQ to chuck it by and
all the turning done at one chucking. It should be made a close fit to R and bolted
tight against DG and ED' with the bolts S3 and 84, clearance being given along the
line HF. To compensate for ware the face DG and ED' can be releaved from
time to time with a file. The base N, should be planed along AB, where it fastens
to the cross slide of the carriage, then bolted to a face plate of the lathe and
finished, care being used to leave the setting of the compound rest unchanged
between machining the faces CD and CD' of the pieces M and N. The dove
tail on R should be first planed and then this bolted to a face plate and the boss
GHFE and the faces KG and EL turned at one setting. If these directions are
followed almost no hand work will be needed. W is a brass worm wheel held by
screws not shown and J is the sliding tool post clamped at X with the tool at K'.

NOTES ON THE ZYGNEMALES.*

Edgar Nelson Transeau.

The following notes principally concerning North American
Zygnemales are based on a study of the specimens accumulated
in the course of eight years collecting in central Illinois; a
collection made by Mr. Charles Bullard, of Cambridge, Mass.,
in Massachusetts and New Hampshire; the specimens dis-
tributed in the Phycotheca Boreali-Americana by Collins,
Holden and Setchell; the specimens distributed in American
Algae, by Miss Josephine E. Tilden; the specimens in the U. S.
National Herbarium ; and small collections sent me by Professor
Farlow, Miss Tilden, Professor A. B. Klugh, Professor D. S.
Johnson and Miss Grace Stone. They have been compared
with the species distributed by Wittrock and Nordstedt in their
"Algae Aquae dulcis exsiccatae, " and other valuable European
and South American specimens sent me by Professors O.
Borge and O. Nordstedt.

In determining almost any species of the Zygnemales it is
absolutely essential that the specimens show both the vegetative
cells and the mature spores. With the exception of a few
species of Mougeotia the spores are colored either yellow,
brown, or blue when they are mature. The characteristic
markings of the median spore wall do not develop usually until
this color appears. Consequently it is useless to attach names
to vegetative specimens based on dimensions and number of
chromatophores. Keys based on such characters are not only
useless, but misleading.

Judging from my experience in Illinois it is highly probable
that the list of North American forms will be considerably
augmented, when intensive studies have been made at localities
in the Southern United States. The most satisfactory method
of collecting these forms is to take samples from the various
ponds and streams at regular intervals of ten days, or two weeks,
throughout the growing season. Many of the species show local
variations and considerable experience is needed before many

*Contribution from the Botanical Laboratory of the Ohio State University.
No. 91.

17

18 The Ohio Journal of Science [Vol. XVI, No. 1,

of the forms can be satisfactorily classified. The writer has in
course of preparation an illustrated key to the group, in which
figures for all of the species will be published.

DEBARYA Wittrock.

This genus is in many respects the most generalized of all
the Zygnemales. It is distinguished by three important
characteristics: (1) the entire contents of the gametangia enter
into the making of the zygospore; (2) the zygospore is formed
in the conjugating tube and is not cut off from the other parts
of the gametangia by partition walls; (3) as the gametes move
toward the tube during conjugation, their place is taken by a
secretion of cellulose, which renders the gametangia solid and
highly refractive. This secretion also occurs when a vegetative
cell forms an aplanospore.

Debarya glyptosperma Wittrock.

This species has been recorded for America. It is not
uncommon in Massachusetts and has also been found in
Minnesota and Florida. In P. B.-A. No. 808 from Boswell,
California is a somewhat smaller variety with blue spores
associated with Zyg?iema peliosporum Wittr. The spores are
common in the material and the vegetative cells and filaments
occasional. Following is a diagnosis for this variety:

Var. formosa nov. var. Cellulis vegetativis 7.5-9^ latis;
zygosporis 24-30^ x 30-42^i, caeruleis; ceterum ut in typo.

Vegetative cells 7.5-9^i in diameter, zygospores 24-30/x x 30-42/x
steel blue, otherwise like the type.

Debarya americana nov. sp.

Cellulis vegetativis 9-12/z x 27-120/x, ad dissepimenta con-
strictis; chromatophoris cum pyrenoidibus 2; cellulis fructi-
feris 10-14/x x 75-180^; zygosporis ovoideis vel quadrato-
ovoideis, 20-40/^ x 30-40 jjl, angulis rotundatis, productis, vel
retusis; parthenosporis 15-20^ x 20-30/x, oblique ellipticis, cum
polls retusis; mesosporio subtiliter et irregulariter verrucoso,
maturitate luteo-brunneo.

Vegetative cells 9-12)U x 27-120/^ constricted at the end walls,
chromatophore with two pyrenoids; fertile cells 10-14/^ x 75-180^;
zygospores ovoid or quadrately ovoid, 20-40/^ x 30-4(V, with
angles rounded, produced, or retuse; parthcnospores 15-20/i-

Nov., 1915] Notes on the Zygnemales 19

X 20-30)U unilaterally ellipsoid with retuse ends; median spore
wall minutely and irregularly verrucose, yellow-brown at
maturity.

This species was collected by Professor A. B. Klugh, Kings-
ton, Ontario. It is the material upon which the Ontario record
for Moiigeotia calcarea (Cleve) Wittr. is based. Of special
interest is the chromatophore with two pyrenoids, which
although an axile plate is distinctly two-lobed and forms an
easy transition to the next species, in which the chromatophore
resembles Zygnema. Type in herb. E. N. T. Collection
No. 2950.

Debarya decussata nov. sp.

Cellulis vegetativis 16-20^ x 25-50^ cylindraceis ; chromato-
phoris asteroidiis duobus, singulis cum pyrenoidibus (ut in
Zygnemate) ; zygosporis vel ovoideis, vel irregularibus, 24-30/x
X 30-48^ cum angulis vel rotundatis, vel retusis, vel productis;
aplanosporis uno latere ovoideis, 17-25^ x 20-40^1; parthen-
osporis 15-20/>i x 20-30/x; membrana media sporarum scrobicu-
lata, luteo-brunnea ; akinetis ad dissepimenta constrictis, mem-
brana subcrassa et glabra, 18-20/^ x 20-36/x.

Vegetative cells 16-20^ x 25-50/x cylindrical; chromatophores
two, stellate, each with a pyrenoid (as in Zygnema) ; zygospores
ovoid, quadrate-ovoid, or irregular, 24-30/i x 30-48/x, with
rounded, retuse, or produced angles; aplanospores unilaterally
ovoid, 17-25At x 20-40iu; parthenospores 15-20/^ x 20-30yu; median
spore walls scrobiculate, yellow-brown; akinetes with smooth
heavy walls, 18-20^ x 20-30)U.

Type in herb, E. N. T. Collections No. 1177, 1939, 1949,
2686 and 2918. I have specimens from several localities in
central Illinois; Williamsport, Pa.; Minnesota; Mackinaw,
Mich, and Kingston, Ontario.

This form is of great interest because of its resemblance,
in the vegetative condition, to Zygnema decussatum (Vauch.)
Transeau. Also because it shows not only the zygospores,
but aplanospores and parthenospores. In all cases the secretion
of cellulose accompanies the process of spore formation. The
unilaterally placed aplanospores are strikingly different from
those formed by the Zygnemas. In some of the Illinois ponds
it regularly produces only zygospores, in other ponds from
which I have collections covering a period of several years it

20 The Ohio Journal of Science [Vol. XVI, No. 1,

fruited only asexually, producing aplanospores and akinetes.
But several of the collections show all the forms of reproduction
in different cells of the same filament.

The characteristics of this species suggest that the peculiar
Zygnema reticulatum, which was described by Hallas in 1895*,
is in reality a Debarya. The fact that the reproductive cells
become filled with cellulose, that the aplanospores are very
irregular in form and that the vegetative cells contain as high
as seven chromatophores, are all in harmony with this idea.
On this basis it is also easy to understand the most notable
peculiarity of the species — that spores derived from cells with
several chromatophores produce two or three sporelings.

With the addition of the two new American species and this
Danish species Debarya reticulata (Hallas) nov. comb, the
description of the genus needs to be modified as follows:

Vegetative cells cylindrical or constricted at the ends,
varying from 1-16 diameters in length; chromatophore varying
from an axile plate with two or more pyrenoids to stellate
chromatophores, each with a central pyrenoid. Reproduction
by zygospores formed of the complete contents of the game-
tangia; not cut off from the gametangia by partition walls;
but in the process of conjugation, as the gametes pass into the
conjugating tube, their place is taken by a secretion of cellulose.
Aplanospores occupying only part of the sporogenous cell, the
remainder being filled with cellulose. All spores variable in
form. Parthenospores and akinetes occur not infrequontly in
some of the species. The walls of the aplanospores and par-
thenospores resemble the zygospores of the same species in
their markings.

There are now eleven described species belonging to this
genus. D. immersa W. West and D. africana G. S. West
bear a close resemblance to Mongeotia sphaerocarpa Wolle.
D. Ilardyi G. S. West has much the same appearance as
Mongeotia viridis (Kutz) Wittrock. D. desmidiodes W. & G. S.
West, D. calospora (Palla) W. & G. S. West, D. reticulata,
D. americana, and D. decussata have characters in common
with the Zygnemas. D. glyptosperma has the vegetative
characters common to several of the species, but its spores are
quite unique among the Zygnemales.

*Hallas, E., Om en ny Zygnema-Art med Azygosporer. Bot. Tidsskrift 20:1-16.
1895.

Nov., 1915] Notes on the Zygnemales 21

ZYGNEMA Agardh.

Z. pectinatum (Vauch.) Agardh.

This is probably common in the eastern half of the United
States at least. In Illinois along with the type occurs the
variety conspicuiim (Hass.) Kirchner, and a variety with large
spores. This latter variety in fact is more common than the
type.

var. crassum nov. var. Cellulis vegetativis 30-40/i x 20-80/^;
zygosporis 40-55/i x 50-60^l, ceterum ut in typo.

Vegetative cells 30-40/x x 20-S0)u; zygospores 40-55/x x 50-60/x,
otherwise like the type. Type in herb. E. N. T. Collections
No. 2350, 2392, 2660, 2685.

Z. ericetorum (Kiitz) Hansgirg.

Professor G. S. West has studied the reproduction of this
species and finds that it is a true Zygnema and that the descrip-
tion and figure by De Bary, which shows the cutting off of two
special gametangia before the union of the gametes is at fault,
consequently there is no longer any need of maintaining the
genus Zygogoniiim Kiitzing.

Z. peliosporum Wittrock.

Specimens of this species have been distributed under the
name of Z. chalybeosperniim Hansgirg, in P. B.-A. No. 808
from Boswell, Calif. (N. L. Gardner) ; Amer. Alg. No. 156 from
Ft. Collins, Colo. (J. H. Cowan); and Amer. Alg. No. 392
from Vancouver, B. C. (J. E. Tilden). Z. chalybeospermum
has the median wall smooth, but the spores of all of the above
specimens have distinctly scrobiculate median walls. In size
the specimens show a somewhat greater variation in dimensions
than has been recorded for European localities.

Z. cruciatum (Vauch) Agardh.

Specimens of this species have been found at Path Pond,
north of Coffeen, 111., in which both zygospores and aplanospores
occurred in abundance. The aplanospores fill or slightly
enlarge the vegetative' cells as in Z. CoUinsianuni Transeau,*
but the ends of the spores are usually more nearly truncate,
34-50m X 30-80At. At Casey, 111., a variety with the same
dimensions but steel blue spores occurs in the old Ice Plant
Pond.

*See Fig. 3, Plate XXV, Amer. Jour. Bot. 1:301. 1914.

22 The Ohio Journal of Science [Vol. XVI, No. 1,

var. caeruleum nov, var. Cellulis vegetativis et sporis ut
in typo, sed membrana media sporarum caerulea.

Vegetative cells and spores as in the type, except that the
median spore wall is steel blue. Type in Collection E. N. T.
No. 495.

Zygnema stellinum (Aliiller) Agardh.

The specimen distributed under the name Z. insigne (Hass.)
Kiitz. in the P. B.-A. No. 457, from Chestnut Hill, Mass.
(G. F. Moore), belongs to this species as shown by the scattered
mature spores. This species is common everywhere in central
Illinois. In the U. S. Natl. Herb, is a specimen from Baltimore
Co., Md., (J. D. Smith). In Amer. Alg. No. 157, a specimen
from St. Paul, Minn., (J. E. Tilden) shows both zygospores and
aplanospores. The aplanospores are cylindric ovoid in form,
occupying the entire cell 30-33jU x 40-88/x, median wall
scrobiculate.

Zygnema cylindricum nov. sp.

Cellulis vegetativis 28-33/x x 28-06^^; zygosporis incognitis;
aplanosporis cylindricis vel tumido-cylindricis, 30-33^ x 24-58//,,
sporangia complentibus ; membrana media brunnea scrbbiculata.-

Vegetative cells 28-33// x 28-66/i; zygospores unknown;
aplanospores cylindric or tumid-cylindric, 30-33// x 24-58/t,
filling the sporangia, median wall brown, scrobiculate. Type
in Herb. E. N. T. No. 1164, 1177.

This species is not uncommon in ponds, and pools through-
out central Illinois. It was at first classified as aplanosporic
material of Z. stellinum (Miiller) Agardh. On going over the
specimens in all my collections, however, it was found that in
no case were the filaments containing the aplanospores con-
nected with the filaments containing zygospores. This must
be the final test of the identity of the species, as it occurs in
some collections alone, sometimes associated only with fruiting
Zygnema pectinatum, and sometimes with Z. stellinum.

Zygnema rhynchonema Hansg.

In a collection of algae made at the Minnesota Seaside
Station, Vancouver Island, B. C, in 19(31, by Professor Tilden,
is a form which perhaps belongs here. The vegetative cells
are from 22-28/x in diameter, and 32-52// in length, while the
European specimens are described as lG-20// in diameter and

Nov., 1915] Notes on the Zygnemales 23

2-6 diameters long. The Vancouver specimens are producing
both aplanospores (globose, 24-26/x in diam.), and zygospores
(ovoid 24-28m x 36-44/i) by the union of gametes through the
partition wall separating the two gametangia. The specimens
show some evidences of being in an abnormal condition.

SPIROGYRA Link.

S. Juergensii Ktitzing.

The specimen in P. B.-A. No. 510 from Knightsville, R. I.,
distributed under the name of 5. longata (Vauch) Kiitz. with
cell diameter 27-30/i, and ellipsoid spores 30-33)U in diameter,
fertile cells enlarged, evidently belongs to this species. The
spores of 6". longata are distinctly ovoid with rounded ends.
In the Illinois specimens the spores of 5. Juergensii frequently
occur with diameters up to 33/x.

S. varians (Hass.) Kiitz.

The varieties scrobiculata Stockman and minor Teodoresco
have not been reported from America. They both occur
rarely in Illinois. The latter I have also seen in material
collected by Mr. Charles Bullard, at Lynnfield, Mass. The
former is characterized by its scrobiculate spores, the latter by
its smaller dimensions throughout. In my herbarium 5".
varians scrobiculata is represented in Collections No. 1799,
and 1881; and S. varians minor in Collection No. 2951.

S. Borgeana nov. sp.

Cellulis vegetativis 30-35/i x 50-200/^, dissepimentis planis,
chromatophoris singulis anfractibus arctis 1.5-5; cellulis fracti-
feris altero latere inflatis, altero latere (in quo conjugatio
sequitur) rectis; zygosporis ellipticis, 33-40^i x 54-70/x, membrana
media flava, glabra.

Vegetative cells 30-35^ x 50-200m, end walls plane, 1 chroma-
tophore making 1.5-5 turns; fertile cells inflated on the outer
side, straight on the conjugating side; zygospores ellipsoid
33-40/i x 54-70/1, median wall yellow, smooth. Type in herb.
E. N. T. Coll. No. 1883, 1890. Charleston, Illinois.

This species bears some resemblance to a form of 6". varians
figured by Professor Borge.* It differs from his figure in
that the conjugating side of the fertile cells is not at all swollen,

*Borge, O., Beitrage zur Algenflora von Schweden.

24 The Ohio Journal of Science [Vol. XVI, No. 1,

and the dimensions are somewhat larger. If this form had been
found but once it would have been passed over as a variation
intermediate between S. Juergensii and 5. varians. But it
has been found several successive years in a small stream south,
and at a small pond west of Charleston, Illinois.

S. lutetiana Petit.

So far as I am aware no specimens of this species have been
found in America. The Illinois record in my list* is an error.
The P. B.-A. specimen labelled S. lutetiana is S.fallax (Hansg.)
Wille, as shown by its often replicate cell walls, verrucose
spores and the number of chromotophores.

S. velata Nordstedt var. occidentalis Transeau.

Specimens of this variety have been distributed in the
P. B.-A. No. 96, under the name of S. diibta Kiitz. var. long-
iarticulata Kiitz. from Oak Bay, Victoria, British Columbia
(N. L. Gardner). The spores are for the most part not mature
but they show the characteristic scrobiculate markings of the
median wall.

S. Lagerheimii Wittrock.

This species is not uncommon in central Illinois. The
specimen labelled S. communis in P. B.-A. No. 1416, from
Winchester, Mass., has a cell diameter over 30/x, and the
spores are ellipsoid instead of ovoid. The median spore wall
in the mature spores is punctate. Here also belongs the P. B.-A.
specimen No. 365, Falmouth, Mass. Both the vegetative cells
and the spores are considerably below the lower dimensions
for 5. porticalis. The P. B.-A. specimen No. 1668, 5. porticalis
var. teniiispira Collins establishes this name as a synonym of
S. Lagerheimii. Professor Farlow has recently sent me a
specimen of this species from Chocorua, N. H.

S. daedalea Lagerheim.

This species has recently been found in a pond south of
Coffeen, 111. The spores show the characteristic markings
and the dimensions are near those of the original collection.
The spores are slightly more rhomboidal than in the type
material, which I have seen. In herb. E. N. T. Collection
No. 2912, 2850.

*Transeau, E. N., Annotated list of the Algae of Eastern Illinois. Trans.
111. Acad. Sci. 6:69-89, 1913.

Nov., 1915] Notes on the Zygnemales 25

S. Goetzei Schmidle.

This species previously known only from the tropics has
been found in the collection of Mr. Charles Bullard, from
Weimeet, Mass. In herb. E. N. T. Collection No. 2954.

S. submarina (Collins) nov. comb.

This species was described by Collins as a variety of S.
decimina (Miiller) Kiitz. which it somewhat resembles in the
form of the vegetative cells. The spores, however, are dis-
tinctly ellipsoid, while those of 5. decimina are ovoid. The
dimensions are much smaller than those of S. decimina. It
seems better therefore to recognize this as a distinct species.
It has been collected in Massachusetts, Connecticut and
Bermuda.

E. ellipsospora Transeau.

Described originally from Illinois, I have seen specimens
during the past year from Maine, Massachusetts and Minnesota.
Professor G. S. West* described about the same time a species
from Columbia, South America, which appears to be a form
of this same species. The vegetative cells are considerably
larger, the chromatophores are six (or five) in number, and
the spores are at the upper limit of size of the North American
form. As our specimens all show, a wider range of dimensions
and number of chromatophores, the South American form is
best classified as a variety under the name 5. ellipsospora var.
splendida (G. S. West) nov. comb.

S. propria nov. sp.

Cellulis vegetativis 60-68^ x 80-150/1, dissepimentis planis;
chromatophoris 3, anfractibus arctis .5-1; cellulis fructiferis
cylindricis; zygosporis ellipticis 42-60/1 x 80-120/i; membrana
media sporarum scrobiculis irregularis ornata, luteo-brunnea.

Vegetative cells 6O-68/1 x 80-150/x, end walls plane; 3
chromatophores making .5-1 turn in the cell; fertile cells
cylindrical; zygospores ellipsoid, 42-60/x x 80-120/t, median
wall irregularly pitted, yellow-brown. Type in herb. E. N. T.
Coll. No. 266G. Coffeen, Illinois.

*West, G. S., A contribution to our knowledge of the Freshwater Algae of
Columbia. Memores de la Societe neuchateloise des Sciences Naturelles 5:1013-

1051. Neuchatel, 1914

26 The Ohio Journal of Science [Vol. XVI, No. 1,

This species is very distinct in the form of its spores and
their position in the fertile cells. Lateral conjugation only
has been observed. It is possible that the number of chro-
matophores is more variable, but in all the vegetative cells in
which they could be counted there were three.

Spirogyra braziliensis (Nordstedt) nov. comb.

Owing to the indefinite and imperfect description of ^.
lineata Suring., the variety Braziliensis Nordstedt, of which
we have a perfect description and specimens (W. & N. Alg.
aq. dulc. exsicc. No. 360), should be given specific rank. Its
connection with S. lineata is very problematical.

S. fluviatilis Hilse.

In all the published descriptions of this species the spores
are described as smooth, and the number of chromatophores
is given as four. I have seen many specimens from Illinois,
and collections from the upper peninsula of Michigan (T. L.
Hankinson), Minnesota (J. E. Tilden), Hawaii (J. E. Tilden),
Massachusetts (P. B.-A. No. 1217), Pennsylvania (E. N. T.)
and Guatemala (W. A. Kellerman). In all cases the mature
spores are brown and scrobiculate, and the number of
chromatophores is three or four.

S. nova-angliae nov. sp.

Cellulis vegetativis 50-60/1 x 200-350^, dissepimentis planis;
chromatophoris 3-5, anfractibus arctis 2.5-4.5; cellulis fructiferis
non inflatis; zygosporis ovoideis 50-65/1x80-120/1: membrana
media sporarum reticulata et dense punctata, flava.

Vegetative cells 50-60/t x 200-350/i, end walls plane; 3-5
chromatophores making 2.5-4.5 turns; fertile cells not inflated;
zygospores ovoid 50-65/t x 80-120/t: median wall reticulate and
densely punctate, yellow in color.

This species was first found in the collections of Mr. Bullard
from Beaver Dam, Brook Pond, Natick; the pond west of
Winter Pond, Winchester; and the Middlesex Fells, Mass.
Recently the same form was found in a large prairie pond south
of Coffeen, Illinois. Its position in the genus is near S. mal-
meana Hirn. In herb. E. N. T. Collections No. 2952, 2953
and 2900.

Nov., 1915] Notes on the Zygnemales 27

S. diluta Wood.

I first came across this species in Mr. Bullard's collection
from the pond west of Winter Pond, Winchester, Mass. On
going over Wood's description, its identity with 5. diluta is
unmistakable. The position, color and form of the spore, and
the shape of the fertile cells is perfectly represented in Wood's
figure. The dimensions also correspond. Wolle is responsible
for confusing this species with 6*. nitida (Dillw.) Link, but a
glance at Wood's figure is sufficient to show that it is very
different from that species. The P. B. A. specimen No. 513
(labelled S. nitida) from Bridgeport, Conn., belongs here. Miss
Grace Stone also sent me a collection of this species from near
New York City. In the U. S. National Herbarium is another
specimen from Bois Sabbi, Louisiana, April 7th, 1891, (A. B.
Langlois). Recently the species has been collected at Donnel-
son, Illinois, by Mr. Frank Harris.

The vegetative cells are usually shorter than in S. nitida,
the spores are ovoid, not ellipsoid, and the spore wall is verru-
cose, or reticulate-verrucose, chestnut brown in color. In herb.
E. N. T. Coll. No. 2900.

S. crassa Kutzing.

Var. formosa nov. var. Varietas gracilis, cellulis vegetativis
80-95m X 80-270yu; zygosporis 88-100^ x 120-150^ x 70-90^; cet-
erum ut in typo.

A small variety, vegetative cells 80-95/1 x 80-270^: zygo-
spores 88-100/1 X 120-150m X 70-90m; otherwise similar to the
type. Type in herb. E. N. T. Coll. No. 1939. This variety
occurs in a pond east of Ashmore, 111.

S. submaxima Transeau.

This species which was described from Illinois has been
found with nearly the same dimensions in the collections from
Middlesex Fells, and South Peabody Station, Mass., sent me
by Mr. Chas. Bullard.

S. micropunctata nov. sp.

CelluHs vegetativis 30-36/i x 120-300/t, dissepimentis planis,
chromatophoris singulis anfractibus arctis 3-7; cellulis fructi-
feris modo binis vel quaternis inter cellulas vegetativas dis-
tributis, modo continuis, altero latere (in quo conjugatio

28 The Ohio Journal of Science [Vol. XYI, No. 1,

sequitur) inflatis, altero rectis; tubo conjugationis plerumque
ex cellula mascula emisso; zygosporis ellipticis 37-42/i x 57-100)U
membrana media micropunctata et lutea.

Vegetative cells 30-30^x120-300^, end walls plane; 1
chromatophore making 3-7 turns; fertile cells scattered in twos
or fours among vegetative cells, or continuous, inflated on the
conjugating side, outer side straight; conjugating tubes formed
almost wholly by the male cell, zygospores ellipsoid 37-42// x
57-70/i, median wall minutely punctate, yellow. Type in herb.
E. N. T. Coll. No. 2470, 2953.

This species was first found in the West Big Four Pond,
east of Charleston, Illinois. It has since been found in a col-
lection from Chocorua, N. H., sent me by Mr. Chas. Bullard.
It evidently belongs in the punctata group of the Spirogyras,
but in form and markings of the spore, and the shape of the
fertile cells it is amply distinct from its nearest allies; 6*.
punctijormis Transeau and the next species to be described.

S. reflexa nov. sp.

Cellulis vegetativis 30-40/x x 120-300/1, dissepimentis planis;
chromatophoris singulis anfractibus arctis 3-8/x cellulis fructiferis
binis vel quaternis inter cellulas vegetativas distributis. inflatis
et valde reflexis; tubo conjugationis ex cellula mascula emisso;
zygosporis ellipticis, 44-54/i x 90-150//, membrana media glabra
et luteo-brunnea.

Vegetative cells 30-40/x x 120-300/x, with plane end wall; 1
chromatophore making 3-8 turns; fertile cells in groups of 2 or 4,
inflated or enlarged and strongly reflexed; conjugating tube
formed by the male cells; zygospores ellipsoid, 44-54/1 x 90-150/i,
median wall smooth, yellow-brown. Type in herb. E. N. T.
Collection No. 2661, 2664, 2912.

This species has been under observation for four years and
has been collected from ponds near Casey, Lerna, Coffeen and
Donnellson, Illinois. The large, smooth spores, the reflexed
conjugating cells, and the tube produced wholly by the male
cells are the distinguishing characteristics.

S. hydrodictya nov. sp.

Cellulis vegetativis 75-100/i x 210-360/x, dissepimentis planis,
chromatophoris 7-10, modo subrectis longitudinalibus, modo
spiralibus anfractibus arctis .1-.5; celluHs fructiferis inflatis vel

Nov., 1915] Notes on the Zygnemales 29

subinflatis; tubo conjugationis ex cellula mascula emisso;
zygosporis lenticularibus vel globoso-lenticularibus, 80-120/x x
110-195^1, membrana media scrobiculis obsita, brunnea.

Vegetative cells 75-100/x x 210-360ju, end walls plane, 7-10
chromatophores, either straight, or spiral making .1-.5 turns;
fertile cells inflated or subinflated; conjugating tube formed by
the male cell; zygospores lenticular or globose-lenticular
80-120// X 110-195/1, median wall brown, pitted. Type in herb.
E. N. T. Coll. No. 2661, 2665. Coffeen, Illinois.

This is one of the most remarkable forms described in this
genus. It combines large size, the lenticular spore form, and
the habit of forming the conjugating tube entirely by the male
cell. The conjugating tube has walls heavier than those of any
known species. Conjugation is both lateral and scalariform,
and occurs between scattered cells, very rarely continuous for
6-8 cells. In the fruiting condition the filaments form a mesh-
work which suggests the specific name. It has thus far been
found only in the Path Pond, north of Coffeen, Illinois.

S. protecta Wood.

A study of American specimens of this species from Massa-
chusetts, Connecticut, New Jersey, Michigan and Illinois,
shows that like S. Grevilleana there are always some cells with
two chromatophores. I have twice found this species producing
aplanospores.

S. tenuissima (Hass.) Kiitz var. rugosa Transeau.

P. B.-A. specimen No. 456, Easton's Pt., Newport, R. I.,
belongs to this variety rather than the type, as shown by the
scrobiculate spore wall. In Mr. Bullard's collection there are
also specimens of the variety from Pennannock, N. J., and from
Spy Pond, Lake St., Arlington, Mass.

S. Farlowii nov. sp.

Cellulis vegetativis 24-30// x 70-180//, dissepimentis repli-
catis; chromatophoris singulis, rarius duobus, anfractibus
arctis 2.5-6; cellulis fructiferis inflatis (ad 39-60/t) ; zygosporis
ellipticis, polls plus minus acuminatis, 32-45// x 48-93/i, mem-
brana media glabra, lutea.

Vegetative cells 24-30// x 70-180//, end walls replicate; 1
(rarely 2) chromatophore making 2.5-6 turns; fertile cells

30 The Ohio Journal of Science [Vol. XVI, No. 1,.

inflated to 39-60At; zygospores ellipsoid, ends more or less-
pointed, 32-45m X 48-93m, median wall smooth, yellow. Type
in herb. E. N. T. Coll. No. 2955, 2956, 2957.

In Mr. Bullard's collection there are specimens of this
species from Lexington, Arlington, and Middlesex Fells, Mass.
The P. B.-A, specimen No. 362, labeled S. Grevilleana, from
Medford, Mass., belongs here, rather than to 5. Grevilleana, in
which the spores are distinctly ovoid with broad rounded ends.

S. groenlandica Rosenvinge.

This interesting form is characterized by quadrately inflated
fertile cells, highly refractive cell walls, and unusually long cells
and spores. In Mr. Bullard's collection there are specimens
from Stony Brook, South Framingham. Middlesex Fells, Way-
side Inn, North Eastham, and Maiden Fells, Massachusetts.
The P. B.-A. specimen No., 363 labelled S. inflafa, Orange,.
Conn., belongs to this species.

S. fallax (Hansgirg) Wille.

This species is one of several forms near 5. insignis (Hass.)
Kiitzing. If Wille's description is correct and identical with
Hansgirg 's material, then S. inconstans Collins becomes a
synonym of 5. fallax. Hansgirg's figure suggests that the
filaments in his material are homosexual. While Wille's
description and figure suggests that the filaments are reflexed
and that conjugation does not regularly occur between parallel
filaments, with the spores all in one filament. It is difficult to
decide just where these rough-spored forms belong as the earlier
authors did not pay much attention to spore markings. In this
connection the note by Professor Nordstedt in connection with
specimen No. 958 in Wittrock and Nordstedt's Algae Exsiccatas
is of interest. Until these forms have been clearly separated by
a study of the original collections it seems best to use S. fallax
for S. inconstans, of which the type is P. B.-A. No. 1568. Here
also belongs P. B.-A. No. 1570, Middlesex Fells, Mass., and
P. B.-A. No. 1571, Wakefield, Mass.

S. floridana nov. sp.

Cellulis vegetativis 56-66/x x 120-335/x, dissepimentis planis;
chromatophoris 4-5, subrectis vel anfractibus arctis .5; cellulis
conjugatis abbreviatis, inflatis (ad 135^) et geniculatis; canalis
conjugationis brevis et latis; zygosporis ellipticis, 75-l()5)U x
95-135/i membrana media glabra, lutea.

Nov., 1915] Notes on the Zygnemales 31

Vegetative cells 56-66yu x 120-335^, end walls plane; 4-5
chromatophores, nearly straight or making a half turn; conju-
gating cells geniculate, shortened; fertile cells inflated up to
135ju; conjugating tube very short and broad; zygospores
ellipsoid, 75-105ju x 95-135/x median wall smooth, yellow. Type
in U. S. National Herbarium, collected by J. D. Smith, in S. W.
Florida, March, 1878.

In its dimensions 5. floridana is intermediate between 5.
stictica (Eng. Bot.) Wille and S. ceylanica Wittrock. In several
publications the statement is made that S. ceylanica is inter-
mediate between S. stictica and the common forms of Spirogyra.
A study of authentic material of this species has shown that it
has not intermediate characters, but with its spores having a
minutely pitted median wall, it seems to be intermediate
between S. floridana and S. illinoiensis Transeau, the most
specialized form in the Sirogonium group of the genus.

Throughout the study of these collections the writer has
been greatly assisted by Mr. Hanford Tiffany, now a teacher in
the Charleston, Illinois, High School. It is a pleasure to
acknowledge my indebtedness to the many collectors who have
sent me specimens for study.

ORGANIZATION OF THE OHIO STATE UNIVERSITY

SCIENTIFIC SOCIETY.

As the result of the sentiment expressed at the 1914 meeting
of the Ohio Academy of Science that the official organ of the
Academy, "The Ohio Naturalist," should be broadened and
made more comprehensive in scope, and feeling that the Ohio
State University had no publication representing the scientific
work being done at the institution, the members of the Biolog-
ical Club of the University, in whom the publication of the
"Ohio Naturalist" had been vested, called a meeting of repre-
sentatives of the various departments interested in science at
the university to discuss the advisability of publishing as
successor to the "Naturalist" a journal to be known as the
Ohio Journal of Science.

The first meeting was held in May, 1915, and committees
appointed to outline preliminary plans. At subsequent meet-
ings the reports of the committees were discussed, interest in
the plan continued to develop, until at a meeting held Octo-
ber 13 the following self-explanatory Constitution was adopted.
The society as now constituted represents twenty-four depart-
ments of pure or applied science at the university.

Raymond J. Seymour,
Secretary Pro Tem.

32

Nov., 1915] Ohio State University Scientific Society 33

CONSTITUTION.

Article I — Name.

The name of this society shall be the Ohio State University
Scientific Society.

Article II — Object.

It shall be the purpose of the Society to promote scientific
work in the University by holding meetings for the presentation
and discussion of the results of scientific work; by co-operating
with other agencies in arranging for scientific lectures and in the
entertainment of visiting scientists and scientific societies; by
publishing the Ohio Journal of Science and by furnishing
opportunity for the discussion and promotion of any project of
scientific interest which may properly come within the scope of
such an organization and, in general, by furthering in every way
possible the interests of scientific work in the University and
the State.

Article III — Membership.

Any member of the instructional staff in the Ohio State
University interested in scientific work shall upon application
be eligible to election to membership in the Society. Students
of the Ohio State University interested in scientific work shall
be eligible to membership when endorsed by two faculty
members of the society.

Article IV — Officers.

Section 1. The officers of the society shall consist of Pres-
ident, Vice-President, Secretary and Treasurer. These officers
shall perform the duties common to such positions.

Section 2. The Executive Committee shall consist of the
officers and the Editor of the Ohio Journal of Science. It
shall have power to arrange programs for meetings, to represent
the society when co-operating with other organizations and to
conduct all affairs of the society not otherwise provided for.

34 The Ohio Journal of Science [Vol. XVI, No. 1,

Article Y — Editorial Board.

The Editorial Board shall be responsible for the manage-
ment of the Ohio Journal of Science. It shall consist of
representatives, one from each department of science in the
university represented in the society membership. This board
shall elect annually an Editor and two Associate Editors.

Article VI — Elections.

Election to membership shall be by vote of the Executive
Committee.

The officers shall be elected by ballot at the annual meeting
in May. Nominations shall be presented by a nominating
committee which shall consist of the Editorial Board.

One member of the Editorial Board shall be elected by each
department from among the members of such department rep-
resented in the society and in case any department fails to elect
a member for this board the Executive Committee shall elect
for the department.

Article VII — Publication.

The Editor and Associate Editors of the Ohio Journal of
Science shall have immediate direction of the publication.
The department editors shall be responsible for the approval
of papers from their several departments, and all papers offered
for publication shall be submitted to such department editors.

The selection for publication from available material shall
be determined by the Editorial Board.

Article VIII — Quorum.

A quorum for the transaction of regular business shall con-
sist of at least fifteen members with a representation of at least
one-third of the departments included in the society.

Article IX — Amendments.

Amendments to the constitution may be made by the con-
currence of three-fourths of the members present at a duly
called meeting, notice of such amendment having been given to
all members at least one week in advance.

Nov., 1915] Ohio State University Scientific Society 35

BY-LAWS.

Article I.

The membership fees of the society shall be twenty-five
cents per year or one dollar for a period of five years and such
fee shall entitle the members to participation in all activities of
the society but shall not include the subscription to the Ohio
Journal of Science.

Article II.

The subscription price to the Ohio Journal of Science
shall be two dollars to non-members, and one dollar and seventy-
five cents to members.

Article III.

The fiscal year of the society shall coincide with that of the
University — July 1st to June 30th. The publication to be issued
during eight months, beginning with November.

Article IV.

Regular meetings shall be held on the second Tuesday
evening of the months of October, November, March, April and
May. The meeting in May shall be the annual meeting for the
election of officers and an editorial board. Other meetings may
be called by the Executive Committee, or by the President on
petition of five members.

Article V.

The University Instructional Staff shall be understood to
include any member of the teaching force.

Article VI.

Amendments to the By-laws may be adopted at any regular
meeting by vote of a majority of the members present, notice of
proposed amendment having been given at time meeting is
called.

THE

Ohio Journal of Science

PUBLISHED BY THE

Ohio State University Scientific Society
Volume XVI D ECEMBER, 10 1 5 No. 2

TABLE OF CONTENTS

Wells — A Survey of the Zoocecidia on Species of Hicoria Caused by Parasites
Belonging to the Eriophyidae and the Itonididas (Cecidomyiidae) 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 ERIOPHYIDiE AND THE ITONIDID^

(CECIDOMYIIDAE).*

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.

*Contribution from the Botanical Laboratory of the Ohio State University,
No. 92.

37

38 The Ohio Journal of Science [Vol. XVI, No. 2,

There are three groups of zoocecidia occurring on hickory
trees :

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

2. Galls induced by species of Phylloxera (Aphididae of the
Hemiptera). Pergandef 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 (Itonididas of the
Diptera). Possibly other genera may be represented on the
hickories, but according to Felt J "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

tPergande, T. "North American Phylloxerinae affecting Hicoria and other
Trees." Proc. Davenport Acad. Sci. 9:185-271, pis. 1-21. 1903.

$Felt, E. P. "The Identity of the better known Midge Galls." Ottawa
Naturalist, Vol. 25, Nos. 11, 12. 1912.

Dec, 1915] Zoocecidia on Species of Hicoria 39

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 proHferation 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 Kiister's* 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,t 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 //. 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 col-
lecting 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.

*Kuster, E. Die Gallen der Pflanzen, Leipzig. 1911.

tCook, Mel T. "Galls and Insects Producing Them." Ohio Nat. 4:140-141.
1904.

40 The Ohio Journal of Science [Vol. XVI, No. 2,

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 //. 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 draw-
ings 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.

Dec, 1915] Zoocecidia on Species of Hicoria 41

The writer wishes to express his appreciation of the hospi-
tahty 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, how^ever,
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 dis-
tinguished with one exception (No. 33) from the very common
Phylloxera galls (Aphididae) 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 cvnipsea (?) (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.

42 The Ohio Journal of Science [Vol. XVI, No. 2,

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

sufBciently drawn out to place the cecidium under this class. 8.
7. Galls spheric, sub-spheric or depressed. 15.
7. Galls sub-cylindric, 23^-3 times as long as wide. 22.
7. Galls obconic, i. e., part projecting from leaf is flat topped, constricted prox-

imally 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, 1^-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 a.symmetric, one side prominently

extended laterally. (18).

19. Small galls, 23^ 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 veryshort, 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).

Dec, 1915] Zoocecidia on Species of Hicoria 43

24. vSmall gall, 2-23''2 mm. high, with flaring base, attached bv 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).

ERIOPHYID^.

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 1-1^ 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 FI. 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, pi. 10, Fig. 260.

ITONIDID^.

3. Caryomyia nucicola, O. S.

"Irregular swelling in the husk produced by the reddish
larvae. Reference to Caryomyia provisional." Felt. "Con-
tain 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

44 The Ohio Journal of Science [Vol. XVI, No. 2,

half an inch long. In July, pale yellowish and contained in
several small hollows, minute whitish larvse, 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 caryavencB 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 larvae 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 larvae, it is barely possible that
Osten Sacken described the empty phylloxera gall above
mentioned containing inquilinous itonid larvse. 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 13^-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, 2Y2 mm. diameter, in the center of
which is a minute light colored papilla.

Rather common on IJ. alba. Collected in Hocking and
Athens counties, Ohio.

Dec, 1915] Zoocecidia on Species of Hicoria 45

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, pi. 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, 23-2 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 \ 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

46 The Ohio Journal of Science [Vol. XVI, No. 2,

the tip thin, spHtting 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 //. 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 flat-
tened 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 13^-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 II. glabra, (Fig. 9a.)

Cylindric-conic, sharply bent over against the leaf, atten-
uate distal part short, not recurved, 3)^ 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 | of gall dome-shaped with 3- many
triangular sides, the flaring base resting on the proximal, con-
stricted or saucer-shaped \', 2-3 mm. high, 3-4 mm. wide. Tip
attenuate, not sharp pointed, however. Light green to yel-
lowish green, the tip darker, reddish to black. Surface smooth
tinder lens. Larval chamber spherical, surrounded by scler-

Dec, 1915] Zoocecidia on Species of Hicoria 47

enchmya 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 Y2~k
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, 23/^-33^ 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, pi. I.

Collected in Hocking County, Ohio, on H. alba. July.

Type specimens at Ohio State University.

12. Caryomyia caryaecola 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. sangiiinolenta 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 13^2
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.

48 The Ohio Journal of Science [Vol. XVI, No. 2,

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. Tri-
chomes 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 //. 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 \ rather sharply constricted from the sub-globular f
of the gall and generally turned to one side. 2 mm. high, iy2~2
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 thick-
ness. Comparatively large region of the base involved in the
attachment of the gall.

Collected in Hocking County, Ohio, on //. a/ba, July.

Type specimens at Ohio State University.

16. Cecidomyia sp.

On leaf, under side, greatly depressed with central, prom-
inent nipple, 3-5 mm. dia. 1^^-23/^ 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.

Dec, 1915] Zoocecidia on Species oj Hicoria 49

A most interesting variant of this form is illustrated in
Fig. IGa. 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 con-
dition 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 asym-
metric 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.

50 The Ohio Journal of Science [Vol. XVI, No. 2,

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, 2-23^ 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 caryae O. S.

On leaf, under side, sub-spherical gall with more or less
prominent apical nipple. 3-33^ 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 //. 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, dis-
tributed 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

Dec, 1915] Zoocecidia on Species of Hicoria 51

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 difi^erent species
but which here is provisionally classed as a variety of C. holo-
tricha, 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 uni-
formly very thick. This type of gall is constant, being col-
lected 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,
2/^-3 mm. wide. Generally wider through one axis. Smooth;

52 The Ohio Journal of Science [Vol. XVI, No. 2,

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 //. 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,
2-2}/^ mm. high. Greenish to dull brown, covered with short,
thin pubescence or smooth. Interiorally from both the prox-
imal and distal sides, truncated, conic processes extend inward,
meeting in the center. From the end of the upper one numer-
ous, 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. thomp-
soni 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, pi. 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 //. microcarpa in Ohio and //. glabra in
Connecticut.

Dec, 1915] Zoocecidia on Species of Ilicoria 53

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 pro-
jecting 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 //. 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 pol-
ished. 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, Kept. Ins. N. Y. 1907. pp. 382, 388, pi. 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, 13<4 mm.
wide at base. Light green at base, changing to yellow, the
distal f 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

54 The Ohio Journal of Science [Vol. XVI, No. 2,

upper side of the leaf to mark the location of the gall beneath.
Resembles Caryomyia tiibicola 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, 2-23^2 rnm. 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.
2-23/^ 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 //. 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

Dec, 1915] Zoocecidia on Species of Hicoria 55

center of which arises a well defined nipple. Dia. across top,
21/^ 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 develop-
ment appear to burst through the epidermis, for gall is sur-
rounded by the ragged collar-like remnant. The rounded
proximal end strongly sunken in the leaf blade which is prom-
inently 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 \]/2 mm. wide. Gall projects from
leaf surface 1-13^ 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, partic-
ularly toward the periphery. At first it was thought that this
gall might be a juvenile form of H. tubicola, but later observa-
tions 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

56 The Ohio Journal of Science [Vol. XVI, No. 2,

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, 23/2~33/^
mm. diameter, 3^2 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 //. cordijormis.

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 larvae within his specimens, but was unable to
determine them as cecidomyid larvae. This gall is thus intro-
duced here, provisionally.

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

Dec, 1915] Zoocecidia on Species of Hicoria 57

EXPLANATION OF PLATES I AND IL

Plate L

Fig. L Mite gall. Eriophyes? sp. X 1§.

Fig. la. Mite gall. Eriophyes? sp. X 5.

Fig. 2. Mite gall. Eriophyes? sp. X 3.

Fig. 5. Cecidoniyia sp. X 4.

Fig. 5a. Cecidomyia sp. Variety. X 4.

Fig. 6. Caryoniyia inanis Felt. X 5.

Fig. 7. Cecidomyia sp. New. X 5.

Fig. 8. Cecidomyia sp. New. X 4.

Fig. 9. Cecidomyia sp. New. X 5.

Fig. 9. a Cecidomiyia sp. New. Variety. X 5.

Fig. 10. Cecidomyia sp. New. X 5.

Fig. 11. Cecidomyia sp. New. X I3.

Fig. 11a. Cecidomyia sp. New. Variety? X 5.

Fig. 12. Caryomyia caryaecola O. S. X 3.

Fig. 13. Caryomyia sanguinolenta O. S. X 0.

Fig. 14. Cecidomyia sp. New. X 5.

Fig. 15. Cecidomyia sp. New. X 5.

Fig. 16. Cecidomyia sp. X 5.

Plate IL

Fig. 16a. Cecidomyia sp. Variety, new. X 5.

Fig. 17. Caryomyia persicoides. Beut. X 5.

Fig. 18. Cecidomyia sp. X 4.

Fig. 19. Cecidomyia sp. New. X 4.

Fig. 20. Caryomyia caryae O. S. X 5.

Fig. 20a. Caryoinyia caryae. Large specimen. X 5.

Fig. 21. Caryomyia holotricha O. S. Isolated specimen. X 5.

Fig. 21a. Caryomyia holotricha O. S. Aggregate condition X 5.

Fig. 21b. Caryomyia holotricha O. S. Bilocular unit of aggregate form. X2.

Fig. 22. Cecidomyia sp. New. X 5.

Fig. 23. Cecidomyia sp. Possibly new. X 5.

Fig. 24. Caryomyia similis Felt (?) X 1.

Fig. 25. Cecidomyia sp. Caryomyia caryae O. wS. (?) X 5.

Fig. 26. Caryomyia tubicola O. S. X 3.

Fig. 27. Cecidomyia sp. New. X 3.

Fig. 28. Cecidomyia sp. New. X 5.

Fig. 29. Cecidozoon (undetermined). New. X 3.

Fig. 30. Cecidomyia sp. New. X 7.

Fig. 31. Cecidomyia sp. New. X 6.

Fig. 32. Cecidomyia sp. X 5.

Fig. 33. Cecidomyia ? sp. X 5.

Ohio Journal of Science.

Vol. XVI, PL.4TE I.

Bertram H^. l^elh.

■•Ohio Journal of Science.

Vol. XVI, Plate II.

Bciham IV. IVells.

THE GEOMETRY OF THE TRANSLATED NORMAL

CURVE.

Carl J. West, Ph. D.

Inixcduct.icn. In curve tracing the graphic representation
is constructed from the equation. Pue largely to the require-
ments 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"^' have found acceptance. In order to
derive curves which can be fitted to widely varying distributions
of points. Professor F. Y. Edgeworthj has proposed to modify,
to translate, the normal probability curve with unit standard

deviation,

t=
1 ~^r
y = / — e

\/27r

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.

* 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.

t Edgerton, F. Y.': — "On the Representation of .Statistics by Means of Analyti-
cal Geometry," Jour. Roy. Stat. Soc, 1914, Feb., Mar., May, June and July.

6o

Dec, 1915] Geometry of Translated Normal Curve 6l

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 probabiUty curve is written:

1 ~ T^
z =

\/27r
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 + Kt2+xt3),

where a, k and X 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

V27r a(l + 2/ct+3Xt-)

The formulas of transformation are thus:
X = a(t + Kt' + Xt^),

1 ~"2~ 1

y =

V27r a(l + 2«t+3Xt^)

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

We have

dy ^ dy d^ ^ l_ ~ T- (3Xt^+2Kt-+(l+6X)t + 2^)

dx dt'dx -\/2^ ^ ' a(l+2/ct+3Xt2)==

62 The Ohio Journal of Science [Vol. XVI, No. 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
X and K, that is, for each translated curve. To determine what
values of X and k give uni-modal curves and what tri-modal
it is convenient to consider the plane of X and k.

The discriminant of the equation

3Xt=* +2Kt2 + (1 +6X)t +2/V = 0
is

IB/c"— k2(1+66X + 117X2)+3X(1+6X)3 = 0

This fourth degree curve crosses the horizontal or X-axis at
X = 0 and at X=-l/6 and when X=0 its equation reduces to
16k^ — K- = 0 or K' = ± 0, K= ^}4:- There is thus contact with the
vertical or K-axis at the origin and that axis is crossed at the
points (0, ±3^^}'). At the point (X=-l/6, k = 0) there is a cusp
with the X-axis for tangent. The other two intersections with
the line X=-l/6 are imaginary, indicating the presence of two
branches to the curve.

The discriminant of the denominator of dy/dx is the
parabola (in X and k),

/c2— 3X = 0

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

(k^— 3X) (16k2— 117X2— 18X—1)—27XH1—24X) =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, IG/c^ — IHX^ — ISX — 1=0, and to the
parabola, k'^ — 3X = 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
X = l/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.

Dec, 1915] Geometry of Translated Normal Curve

63

Values of A and k for points on the discriminant give curves
with two modes coinciding. All points on one side of the dis-
criminant 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 /c = 0 the modal equation
becomes

3Xt-'* + (l+6X)t = 0

Hence the roots are t = 0 and t

1 + 6X.

3X

The quantity

under the radical is positive for values of X between 0 and -1/6,
Therefore, all points within the discriminant curve yield
tri-modal curves and all without uni-modal curves.

The plane of \ and K

K

Fig.!
( The horizontal 5cale js twice the vertical scale)

The infinite values of dy/dx arise from zero values of the
quadratic, l+S/ct+SXt^. 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.

64

The Ohio Journal of Science [Vol. XVI, No. 2,

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

3Xt2+2/ct + l=0

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

The parabola, k" — 3X=0, obtained by equating the dis-
criminant of this quadratic to zero separates the points on the
(X, k) plane which correspond to curves of no infinite points
from those corresponding to curves of two infinite points.

Types of Cori/es

Therefore, all pairs of values of X and k 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 corre-
sponding to values of X and k in each of the distinct regions of
the plane of X and k.

Dec, 1915] Geometry of Translated Normal Curve 65

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 (X, k) moves from the X-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 K-axis to the left one asymptote rnoves o.'T 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 X-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-modai Curves. The curves corresponding to values
of (X, k) 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

3Xt- + 2Kt-fl=0

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

27X— 6k-M=0

As statistically promising within the discriminant of the
■cubic we then have the shaded area of the (X, k) plane.

66 The Ohio Journal of Science [Vol. XVI, No. 2,.

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 corre-
ponding 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, K and X.

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 ju, we have

1 r+°°

^^' = N J _. ""^^

N
Ma

1 r+°°
1 r+'"
1 r+°°

where N is the total area under the curve.

The values of the yu's are computed from the data* 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, merel}' the princi])al results will be given.

*Elderton, 1. c.

Dec, 1915] Geometry of Translated Normal Curve 67'

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

1 c

, ^L- r ° ^;f +f' +,\n: e " ^a(l + 2«t+3Xt')dt
-w^N^— a(l + 2/ct+3Xt') V r I y

= ,1^ f " a-^Ct+Kt'+Xt^j^e ~ T~dt

V 27r N ^ —

On applying the two well known formulas :

+ CC

x^"+^e-"Mx= %^ x^"e--Mx,

CO 2 •^ CO

the determination of ju/, )U2', Ms' and jii is reduced to a matter of
algebraic detail. Then on transferring to the arithmetic mean
as origin the values of )U2, Ms, and m4 can be determined in terms.
of a, K and X. It is most convenient however, to make use of
the quantities /3i = m3Vm2"'' and /32 = M4/m2^ or rather jS = /5i/8 and
€ = (/32 — 3)/12 and express the constants in terms of these
quantities. It is to be noted that both e and j8 are zero for a
normal distribution, that is, for X = /< = C.

Omitting the detailed reduction* which is straightforward
and direct, we have

(1) n' = aK

(2) M2 = a2(l+6x+15x2+2/c2)

2k2(2/c='+Q)2

(3) 13

^^^ ' (2k2+R)2

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

S =1 + 18X + 90X2,
R = 1+6X + 15X2,
Q = 1.5 + 18X + 135/2X2,
T =2X + 36X2+270X3+810X4.

* Compare Edgeworth, "A Method of Representing Statistics by Analytical
Geometry," Proceedings Fifth International Congress of Mathematicians,.
Cambridge, 1912.

■68 The Ohio Journal of Science [Vol. XVI, No. 2,

Obviously no algebaric solution can be obtained from
equations (3) and (4) for k and X in terms of the computed values
j8 and e, and hence a resort to tables is necessary. The values of
j8 and e for values of k from 0 to 0.0335 and of X from -0.040 to
+0.100 have been computed.* The process of determining the
constants of the translated normal curve consists first in com-
puting /5 and e from the given data, and then in entering the
table and interpolating for the corresponding values of k and
X.f On substituting these values in (2) the value of a can be
found and thence on multiplying a by k the position of the
median of the distribution is obtained.

The sign of k is determined by the sign of the third moment
about the mean ixz, that is, by the direction of the skewness or
asymetry. For positive skewness the mean must lie to the right
of the median and hence ixi , the first moment about the mean,
must be positive which necessitates a positive sign for k.
Therefore, the sign of k 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

aXt^ + a/ct" + 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. J The distinctively geomet-
rical operation is the interpolation for the values of X and k for
a given pair of values of jS and e.

Within the limits of the table § the curves resulting from the
assignment of a constant value to jS are practically straight

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

fCompare "Tables for Statisticians and Biometricians," Caml)ridge Uni-
versity Press, 1914.

JFor the statistical details see Elderton, 1. c.
§As may be seen on examining the Table.

Dec, 1915] Geometry of Translated Normal Curve 69

lines, ^ = 0 is the X — axis ; |S = 1 is a line parallel to the X — axis.
Hence we may safely assume that the variation from one col-
umn to the next and from one line to the next is linear for
values of /3. That is, ordinary first difference interpolation
methods are applicable.

As regards the system of e curves we have for instance
€ = .128 at (X = .050, /c = 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 e curves.

As an illustration let us find the values of X and k for e = 0.112
and j8 = 0.044. On inspection of the table it is seen that X lies
between 0.30 and .035 and k between .090 and .095. When
K = .090, X = .033 for e = .112. When k = .095, X = .031 for e = .112.
For ,3 = .042 and k- = .090, X = .033 and for /3 = .046 and k' = .095,
X = .031, € = .112 in each case. Hence, to first differences,.
X = .032 and k = .093 for € = . 1 12 and /3 = .044. For interpolation
in parts of the table showing more rapid variations appropriate
methods will suggest themselves.

Taken geometrically the table represents two distinct sys-
tems of curves, with each curve of one system intersecting all
the curves of the other system. Therefore, a pair of values for
X and K can always be found for values of e and 8 within the
range of the table.

Department of Mathematics, Ohio State University.

TABLE OF e AND (i.

( € is the first and /3 the second number of each pair.)

-040 -035 -030 -025 -020 -015 -010 -005 000 005 010 015 020 025 030 035 040 045 050

000 -061 -056 -050 -043 -035 -027 -019 -010 000 010 021 033 045 057 071 084 098 113 128
000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000

005 -055 -049 -042 -035 -027 -019 -010 000 010 021 033 045 057 071 084 098 113 128
000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000

010 -055 -049 -042 -035 -027 -018 -010 000 Oil 022 033 045 058 071 085 099 113 128
000 000 000 000 000 000 000 001 001 001 001 001 001 001 001 001 001 001

015 -049 -042 -035 -027 -018 -009 001 Oil 022 034 046 058 071 085 099 114 129
001 001 001 001 001 001 001 001 001 001 001 COl 001 001 001 001 001

020 -048 -041 -034 -026 -017 -008 002 012 023 034 046 059 072 086 100 115 130

001 002 002 002 002 002 002 002 002 002 002 002 002 002 002 002 002

025 -047 -040 -033 -025 -016 -007 003 013 024 035 047 060 073 087 101 116 131

002 002 002 003 003 003 003 003 003 003 003 003 003 003 003 003 003

030 -046 -039 -032 -024 -015 -006 004 014 025 036 049 061 074 088 102 117 132

003 003 004 004 004 004 004 004 004 004 005 005 005 005 005 005 005

035 -045 -038 -031 -023 -014 -005 005 015 026 038 050 063 076 089 104 118 133

004 005 005 005 005 005 006 006 006 006 006 006 006 007 007 007 007

040 -037 -030 -022 -013 -004 006 017 028 039 052 064 077 091 105 120 135

006 006 007 007 007 007 007 008 008 008 008 008 008 009 009 009

« 045 -036 -028 -020 -Oil -002 008 019 030 041 053 066 079 093 107 122 137

008 008 008 009 009 009 009 010 010 010 010 Oil Oil Oil Oil Oil

050 -034 -026 -018 -009 -000 010 021 032 043 055 068 081 095 109 124 139

009 010 010 Oil Oil Oil 012 012 012 012 013 013 013 013 014 014

055 . -032 -024 -016 -007 002 012 023 034 045 057 070 083 097 111 126 141
Oil 012 012 013 013 013 014 014 015 015 015 016 016 016 016 017

060 -022 -014 -005 004 014 025 036 048 060 073 086 100 114 129 144

014 015 015 016 016 017 017 017 018 018 019 019 019 019 020

065 -020 -012 -003 006 017 028 039 050 062 075 089 102 116 131 146

016 017 018 018 019 019 020 020 021 021 022 022 022 023 023

070 -018 -009 000 009 019 030 041 053 065 078 091 105 119 134 149

019 020 020 021 022 022 023 024 024 025 026 026 026 026 027

075 -015 -007 002 012 022 033 044 056 068 081 094 108 122 137 152

022 023 023 024 025 026 026 027 028 028 029 029 030 030 031

080 -013 -004 005 015 025 036 047 059 071 084 097 111 125 140 155

025 026 026 027 028 029 030 031 031 032 033 033 034 034 035

085 -001 008 018 028 039 050 062 075 088 101 115 129 144 159

029 030 031 032 033 034 034 035 036 037 037 038 039 039

090 002 Oil 021 032 043 054 066 079 092 105 119 133 148 163

032 033 034 036 037 038 039 039 040 041 042 042 043 044

095 005 015 025 035 046 058 070 083 096 109 123 137 152 167

036 037 038 039 041 042 043 044 045 046 046 047 048 049

100 009 018 028 039 050 062 074 087 100 113 127 141 156 171

039 041 042 044 045 046 047 048 049 050 051 052 053 054

A PRELIMINARY LIST OF THE J ASSOIDEA 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 Jassoidea 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.

71

iZ

The Ohio Journal of Science [Vol. XVI, No. 2,

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 Spring-
field on grass.
Kolla tripunctata Fitch. Mentioned in VanDuzee's Catalogue

of Described Jassoidea of N. A. as occurring in Missouri.
Tettigoniella gothica vSign. 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 hieorglyphica Say. var. hieroglyphica Say. One

adult captured from grass at Rolla, September 21, by Mr.

Geo. W. Barber.

Dec, 1915] Jassoidea of Missouri 73

Tettigoniella hieroglyphica Say. var. uhleri Ball. Rather com-
mon in eastern half of state. Taken from clover and weeds.

Tettigoniella hieroglyphica Say. var. confiuens 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. Com-
mon on several ornamental plants and shrubs in the
Missouri Botanical Gardens at St. Louis during September.

Draeculacephala reticulata Sign. Rather common at Charles-
ton 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 distri-
bution 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.

74 The Ohio Journal of Science [Vol. XVI, No. 2,

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 numer-
ous 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 speci-
mens 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.

Dec, 1915] Jassoidea of Missouri 75

Deltocephalus albidus Osb. & Ball. Recorded from the collec-
tion 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.

7G The Ohio Journal of Science [Vol. XVI, No. 2,

Phlepsius irroratus Say. Very common and generally dis-
tributed 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 sum-
mer months. Generally distributed but not abundant.

Phlepsius superbus Uhler. Not abundant. Occasional spec-
imens 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 wil-
lows. 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 Charles-
ton 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.

Dec, 1915] Jassoidea of Missouri 77

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 Pat-
tonsburg 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.

78 The Ohio Journal of Science [Vol. XVI, No. 2,

Typhlocyba comes Say. var. vitis Harris. Occurring on orna-
mental 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 Sa3\ 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 Entom-
ology; 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 Uni-
versity Scientific Society for the year: President, F. C. Blake,
Department of Physics; Vice President, Jas. R. Withrow,
Department of Chemistry; Secretary, R. J. Seymour, Depart-
ment 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.

79

80 The Ohio Journal of Science [Vol. XVI, No. 2,

The Ohio Academy of Science at its November meeting
voted to change the date of its annual session to a time cor-
responding 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

Ohio Journal of Science

PUBLISHED BY THE

Ohio State University Scientific Society

Volume XVI JANUARY, 1916 No. 3

TABLE OF CONTENTS

Earhart — Notes on the Electrical Behavior of Porcelain and Glass at

Moderately High Temperatures 81

Sears — Evaporation and Plant Zones in the Cedar Point Marsh 91

McCall — A Method for the Renewal of Plant Nutrients in Sand Cultures 101

Schaffner — Additions to the Catalog of Ohio Vascular Plants lOi

Melchers — Plant Disease Exhibit Cases 105

Rice — Ohio Academy of Science. Quarter Centennial Anniversary 109

NOTES ON THE ELECTRICAL BEHAVIOR OF

PORCELAIN AND GLASS AT MODERATELY

HIGH TEMPERATURES.

RoBT. F. Earhart.

(Paper read at the Oberlin meeting of the Ohio Academy, Nov., 1913.)

The experiments described were carried on by the author
during the fall and winter of 1912-1913.

They were suggested by an earlier experiment performed
several years ago on the conduction of electricity through
gases at high temperatures. During these earlier experiments
certain gases were contained in glazed porcelain vessels and
subjected to temperatures of 500° and 600° C. It was noted
at that time incidentally that when the porcelain was subject
to a high e. m. f., a current of some magnitude traversed the
porcelain and that while the e. m. f. was steady the current
through the porcelain steadily decreased with time.

Soon after this I suggested an experiment to Mr. Henderson,
a student in Ceramics in the Ohio State University, and Mr.
Geo. Weimar of the Electrical Engineering Department, which
they undertook as a joint thesis. Their experiment consisted

Si

82 The Ohio Journal of Science [Vol. XVI, No. 3,

in applying a potential difference to porcelain bodies which
were varied in temperature and determined the dielectric
strength of the porcelain at different temperatures. They
made a large number of such bodies, of different composition
and of a form adapted for use in an electrically heated furnace.
They measured the potentials required to break down such
insulators.

In general when such a body breaks down under electric
stress a mechanical puncture results and the body ceases to
become an effective insulator when again subject to high
potentials. Messrs. Henderson and Weimar found that when a
temperature of 300° C. was reached, they had difficulty in
building up a potential to a value where a definite and sharp
break indicated a puncture of the dielectric. Instead of
obtaining such a definite value a rather indefinite one was
obtained in which a phenomenon somewhat similar to break
down occurred. They discovered also that when these insula-
tors were cooled to room temperatures that their insulating
properties had not been impaired in the slightest. This
indicated that instead of producing a mechanical break down
of the material such as was attained at lower temperatures, the
failure to insulate was due to a change in conductivity of the
bodies.

Soon after this, experiments were reported by A. A.
Sommerville of Cornell University and W. W. Stifler of the
University of Illinois* on the resistance of similar bodies at
high temperatures. The methods employed were the usual
Wheatstone bridge methods for determining resistance in
which a small e. m. f. was used.

Fleming, in his discussion of cable insulation, points out
that such a method is open to serious objection on account
■of the polarization of the dielectric.

The effect of applying an e. m. f. develops a back e. m. f.
and the condition for establishing a bridge balance becomes a
function of the true resistance of the arm containing the speci-
men and the e. m. f. of polarization as well. The whole question
of the resistance of such bodies is an open one. The trans-
mission of current through such bodies has been regarded at

1^* Physical Review, April, 1911, p. 429.

Jan., 1916] Electrical Behavior of Porcelain and Glass 83

times as similar to metallic conduction, at other times as
electrolytic in character. It is possible that these ceramic
bodies fvmction in both manners.

The author undertook these experiments without expecta-
tion of answering this question, but to obtain some experimental
data on the magnitude of the currents obtained by Plenderson
and Weimar in their experiments, also to find if possible whether
one could give a true ohmic value to the resistance offered by
the porcelain bodies at temperatures where they became very
appreciable conductors. Henderson and Weimar had used
periodic e. m. f's. from a 60 cycle source. The general plan
here adopted was to employ the high potential storage battery
in our laboratory for maintaining constant and fairly high
potentials (up to 1,000 volts) and apply the potentials directly
to the specimen at the same time measuring the current.
Then from Ohm's Law we could infer the resistance

Vi-V2 = RI.

Vi — Vo = potential difference in volts.
I = current in amperes.
R — resistance in ohms.

Figure 1 shows the very simple arrangement of the circuits.
The battery has one terminal earthed. The other terminal was
connected to the specimen (S) through a high resistance (R).
A Weston volt meter (V) with a multiplier (M) measured the
potential difference between the upper face of the specimen and
the earth. The regulating resistance (R) made it possible to
maintain a constant potential if desired. The regulating
resistance was a liquid contained in a tube 80 cm. long, 2 cm. in
diameter.

The liquid is a solution 25% saturated of Cadmium Iodide
in Amyl alcohol. The terminals are Cadmium. This gives
a high resistance quite free from polarization and capable of
carrying currents of 50 milliamperes.

The ammeter (A) introduced between the specimen and
earth measured the current passing through the specimen only.
This consisted of a resistance with a D'Arsonval galvanometer
in shunt. Knowing the resistance of shunt and galvanometer
one can calculate the fall in potential through the specimen
for any values given by the voltmeter. Through the courtesy
of the Ceramics Department, samples of porcelain were secured

84

The Ohio Journal of Science [Vol. XVI, No. 3,

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Jan., 1916] Electrical Behavior of Porcelain and Glass 85

of the same kind as those used by Henderson and Weimar.
These were moulded in the form of cyhnders 2 cm. in diameter
and 2 cm. in length. The ends were ground plane. The
method of mounting and operating upon them is shown in
Figure 2.

The furnace proper consisted of two porous battery jars
with bottoms removed, placed end to end. Over this resistance
wire was wound. This was covered with asbestos paste and
baked on. The furnace was then placed in a section of asbestos
steam pipe jacket. A thermo couple (T) projected into the
chamber of the furnace. It was a Pt Rh-Pt couple which
had been calibrated for other work.

A thick rod of copper (C) projected from below into the
heating chamber. This rod had a copper cylinder (E) screwed
to the top. The upper surface of the cylinder was covered
with Platinum which was securely fastened to the copper
cylinder both mechanically and electrically. This Pt surface
served as an electrode which pressed against one face of the
porcelain cylinder. Platinum was used because it would not
oxidize at the temperatures attained. Above the specimen (S)
a rod similarly terminated rested on the upper face of the
cylinder. This rod had freedom of motion through guides.
Changes in length due to expansion were provided for in this
manner; it also insured that the specimen would be subjected
to a constant pressure during the experiment. A series of
mica vanes placed at intervals about the rod served to reduce
heat losses due to convection.

Such a furnace can be regulated by hand, within reasonable
limits. The large heat capacity and low conductivity of the
materials entering into the construction serve to iron out small
fluctuations of current strength. It was found that a steady
temperature of 500° C. could be obtained five or six hours after
turning on the current and that this could be maintained
constant plus or minus 3° for a period of several hours. With
such a device when a potential difference is applied, current
flows through the ammeter. The specimen is so mounted that
the stream lines of flow, such as we ordinarily consider, are
perpendicular to the electrodes and parallel to the axis of the
cylindrical specimen. The current we wish to measure is of
this character. We will call this the Number One type. There

86 The Ohio Journal of Science [Vol. XVI, No. 3,

are two other possibilities. Number two, a possible creepage
or leakage from one terminal to another over the surface of the
porcelain.

Number three, a current passing through the hot gases
surrounding the body.

The third type is present if we raise the temperature to a
point where the interior begins to glow and apply a sufficiently
high potential. When an appreciable current passes through
the gas it becomes luminous and is readily observed. It is
characterized by appearing suddenly when a critical potential
is attained and is large compared with the Number One type
of current. The effect can be avoided only by operating over
potentials which should be kept below 350 volts. This places
a decided limitation in the form of apparatus shown in Figure 2.

Anticipating the results slightly it may be said that leaving
out of account the gas discharge, the current passing through
the ammeter and through the porcelain appeared to be separable
into two parts, one which decreases rapidly with time and one
which if it changes at all changes at a much lower rate. It was
thought that this might be due to some alteration in surface
condition and this was borne in mind while making the tests
in porcelain. It did not seem feasible to alter the form of
apparatus to prevent the possible surface leakage in the case of
porcelain. It may be remarked also that while the values of
current strength differed somewhat from different cylinders, all
results were of the same general character.

The next step in the experiment was to make a glass cylinder
of the same form as the porcelain cylinders previously described.
Only one such cylinder was used and while it showed appreciable
conduction at lower temperatures than did the porcelain, the
general characteristics of current-time were the same, namely, a
large initial current which decreased with time.

Next a glass cylinder of the form shown in Figure 3 was
used. This was designed to eliminate both the possibility of
gas conduction and leakage over the surface. The glass cyl-
inder was continued at the upper edge by a glass tube which
extended nearly the entire length of the copper rod. A guard
ring shown in the figure (R) was wound around this tube and
earthed. The rod inside the tube rested on the glass cylinder
as before and was terminated with platinum. In this case if

Jan., 1916] Electrical Behavior of Porcelain and Glass 87

creepage over the surface occurred the leakage current would be
diverted to earth and the ammeter would register only the
current passing through the cylinder specimen, i. e., the Number
One type. It was not convenient to make this cylinder of
the same dimensions as the one previously used, but the
characteristics of the current time curve were the same as in the
previous cases. This would indicate that the characteristic
curves of all were of the same kind and were due to the volume
conduction of the specimens rather than leakage over the
surface.

Discussion of Results.

A few preliminary trials indicated that it was not possible
to fix the resistance of the porcelain or glass bodies by the
simple application of the formula suggested earlier in this
paper. The current strength was found to be a function of the
material, dimensions, temperature and potential applied, also
it depended upon the length of time of application of the e. m. f.
The apparent resistance could have wide variations in value
which seemed to be limited only by the time of application of
the e. m. f. We are accustomed to think of the resistance of a
conductor as having a definite and fixed value determined by
the dimensions and temperature of the conductor. Our legal
definition of the ohm is of this kind. In such a sense these
ceramic bodies at temperatures where they become appreciably
conducting have no definite resistance.

The usual method of study was to obtain a predetermined
temperature and maintain it at a constant value through a
single experiment. A potential was applied which was left
constant and the current noted at time intervals. Figure 4
shows a typical curve. This was made on glass, with the
guard ring arrangement, hence current values are for those
which must pass through the glass.

The current decreases initially very rapidly with time and
then at a much diminished rate. The units shown as ordinates
are 10-^ amperes and on this scale the values may be shown
over a long period. The first value shown in Figure 4 is one
taken one minute after the potential was first applied. The
earlier values are much larger and cannot be shown on this
scale. The general procedure was to take current readings
every 15 seconds during the early stage for say five minutes,

88

The Ohio Journal of Science [Vol. XVI, No. 3,

then at minute intervals and finally at much greater intervals.
When a new specimen is taken the initial currents are of the
order of several milliamperes for a few seconds. Such measure-
ments were made but it is difficult to obtain accurate current
measurements where the values diminish so rapidly. The
difficulty which Henderson and Weimar experienced in obtain-
ing definite break down readings are, I think, a little better
understood from the nature of these curves. In using a 60
cycle current a potential which increased from zero value to
maximum value in 1-240 of a second was applied; this decreased

•so as

Time i-n TYIiriutes

to zero and was then reversed in direction. In such intervals
of time only a feeble back e. m. f. is developed and the current
no doubt has a large value. Their difficulty in building up a
definite potential was due to the fall in potential which occurs
when a current passes. The continued decrease in current
as time progresses is due undoubtedly to a back e. m. f. which
may attain any value short of the applied e. m. f.

Persistence of the hack e. m. f. — A considerable part of the
experimental work in this connection was done in studying the
ability of these bodies to retain an e. m. f. set up in them.

It was found for example that after the curve had been
followed out to the flat portion, that the e. m. f. might be
removed for a short time (say two minutes) and the curve

Jan., 1916] Electrical Behavior of Porcelain and Glass

89

taken up on reapplication of the e. m. f. without any dis-
crepancy. If a half hour elapsed the first values would be
somewhat larger than when the e. m. f. was withdrawn.

In some cases after application for a half hour in one direc-
tion the battery was reversed. The effect of this was to have
the impressed e. m. f. of the batteries acting in the same
direction as the previously generated back e. m. f. The time
current curve showed this boosting effect, the initial values of
the current were larger and the time taken for the curve to
attain the flat portion was much longer.

"'jTfl

1

Fij.5

.

lemi

)S30

1

Pot =

53¥vo

its

5

\

o

6

^

^^

' 0-^

J

«

1

-6

I.S

13

30

35

■^S

■So

Time Jn THinutes

This boosting effect was apparent even when the specimen
was cooled to room temperature and reheated. The reversal
was effected in two ways: First, by reversing the battery;
Second, by taking the specimen out after cooling and turning
it end for end. This latter process had the effect of reversing
the specimen only leaving the terminals unaltered. The
effect was the same and the effect of previous polarization was
unmistakable.

Figures 5 and 6 are companion curves for Figure 4 and are
introduced for the purpose of showing the retention of the
polarized state. Figure 4 is the first run made in a glass
cylinder which, so far as I had means of knowing, had never-
been treated electrically.

90

The Ohio Journal of Science [Vol. XVI, No. 3,

The first reading shown was taken one minute after the
potential was applied. This was permitted to cool to room
temperature and remain in that condition without the applica-
tion of a potential for two days. The specimen was reheated to
■approximately the same temperature as before and the same
potential applied. Figure 5 shows the result on the same scale.
The first reading shown is smaller than the first one in Figure 4
and was taken 15 seconds after the potential was applied. The
potential indicated was left on for four hours and the specimen
then allowed to cool. It was reheated after 20 hours and the
curve in Figure 6 obtained.

Fiq.

(n

Tp.mx}.

530"

P^
5

J

Po

volts

f

to

L

~— • c

0 (

t

^

a

0

^

i /

d 1

<i' 2

to 3

-s 3

0 3

s 4

0 4

if ^

B

Time m ITI mutes

This and many similar experiments show that the resistance
of bodies of this character cannot be determined in a satis-
factory way by direct current measurements. The behavior
of the body is determined in part by its previous history. In
this respect it is analogous to the behavior of magnetic bodies.
It would be of interest to put these bodies through a cycle such
as is done in the study of magnetic hysteresis. In fact a possible
way of throwing more light on the interesting and difficult
subject of dielectric hysteresis might be carried out in this
manner. The author had in mind attempting such a series
of experiments, but the close temperature regulation required
.and the length of consecutive time required to take a series of
observations did not appear feasible for one carrying a teaching
schedule.

Physical Laboratory, Ohio State University, December, 1915.

EVAPORATION AND PLANT ZONES IN THE CEDAR

POINT MARSH.*

Paul B. Sears.

Yappi in trying to account for the xerophytic structure of
marsh plants by means of evaporation studies has shown a
definite correlation to exist between the strata of marsh vegeta-
tion and rates of evaporation at corresponding levels. The
following studies were made in an attempt to discover what
additional correlations, if any, exist between distribution of
marsh plants and the evaporational power of the air at different
portions of the habitat. While the exact quantitative sig-
nificance of such work as the following may be brought into
question, as it often is, the striking results obtained by
Transeau,^ Livingston,^ Fuller,-* Weaver,^ Yapp,^ and others,
show that when such work is carefully done it is of unusual
efficiency, considering its extra-laboratory character.

The studies were carried on in the strip of marsh between
Beimiller's Cove and Fred's Cove, at Cedar Point, Ohio.
The physiography of this region has been beautifully worked
out by Mosely," while we are indebted to Jennings^ for an
excellent account of the phytoecology of Cedar Point. A
glance at the accompanying maps^ will make clear the nature
of the region studied. It is a cove marsh along the inside of
the lengthy sand-bar (Cedar Point) which, forming across
the sunken mouth of the Sandusky River, has served to prac-
tically separate Sandusky Bay from the rest of Lake Erie.
Save for the occasional violent northeasterly winter gales
which have served to pile up Cedar Point, the prevailing
winds here are largely from the southern and western quarters
of the compass.^

Zonation is certainly the most obvious phenomenon of
plant distribution in the marsh, and was chosen as the feature
most profitable for investigation. Beginning with the outer-
most zone of severely exposed vegetation the following clearly
defined zones are encountered in order:

* Contribution from the Botanical Laboratory of the Ohio State University,
No. 93.

91

92

The Ohio Journal of Science [Vol. XVI, No. 3,

The Scirpus Zone — This is a region of extreme exposure so
far as vegetation is concerned, and includes points 50 to 100
feet (15 to 30 metres) offshore from the bar. The water here

ADAPTKD FROM MOSLEY'S ".SANDUSKY FLORA."

is about three feet (.9 metre) in depth, with a sandy, much-
washed bottom. The only form of emersed plant life here
is Scirpus validus in more or less scattered clumps.

Jan., 1916]

Evaporation and Plant Zones

93

The Dianthera Zone — This comprises the western and south-
western edge of the bar, as indicated on the map. Fig. 3, and is
consequently more or less exposed to the prevalent winds. The

Lake

LA6T

^AHDUmr

Bay

:'.': Sand

water depth here ranges around six inches (1.5 decimetres),
with a bottom that is sandy, well washed, and that has a very
slight admixture of dark organic material indeed. The domi-

94

The Ohio Journal of Science [Vol. XVI, No. 3,

nant species here is Dianthera americana, present in con-
siderable abundance, with a few plants of Scirpus americanus,
Scirpus nanus and Carex sp.

s5 Scirpuj

D Didvtherd

C Cdldmdcrcjtij

Pn PonteJerid
Cs Cd^tdlid
Sp Spdr^dnium

Ty Typhd

6d Spirodeld

nred included. 1000>^1Z60 It. (J01.8 - OSW A)

The Calamagrostis Zone — Wherever the sandbar actually
rises above water level, it is covered with this distinctive type
of vegetation. Anything above the height of the Dianthera

Jan., 1916] Evaporation and Plant Zones 95

here receives considerable exposure to the winds from the
prevaiHng quarter, obviously. The soil is almost pure sand,
averaging about four to six inches (1 to 1.5 decimetres) above
water level. The vegetation in this area so restricted is almost
exclusively Calamagrostis canadensis with scattered and small
individuals of Salix longifolia.

The Phragmites Zone — Behind the Zone just mentioned the
sandbar extends for some distance, but is nowhere emersed.
The depth of water at this portion of the habitat fluctuates,
generally being less than three inches (.7 decimetres), and the
sand contains a considerable amount of organic material.
Phragmites phragmites flourishes here almost exclusively, the
only invaders being occasional sickly plants of Dianthera and
scattered small colonies of Spirodela polyrhiza. The luxuriant
tops of the Phragmites compel rather wide basal spacing of
the plants, giving room for such invasion as does occur.

The Pontederia Zone — Along the inner or northeasterly
edge of the sandbar just mentioned the water again deepens,
composing an extremely sheltered zone, hence one very rich in
organic detritus. The water depth here ranges between six
and twelve inches (1.5 and 3 decimetres), and the dominant
species is Pontederia cordata while Sagittaria latifolia is present
in considerable amount, with Carex sp. and stragglers of
Dianthera and Sparganium.

The Castalia Zone — The sandbar mentioned above is suffi-
ciently long to form a tiny sheltered cove to the northeast, as a
glance at the map will show. Actually this little cove is a mere
recess at the western end of the larger Ned's Cove. Needless
to say the bottom here is heavily covered with mucky organic
matter, and the water, which ranges from one to four feet
(.3 to 1.2 metres) is quiet. The conspicuous and abundant
species here is Castalia tuber osa, while there is a plentiful
admixture of Nymphaea advena, Nelumbo lutea, Utricularia
vulgaris, Potamogeton natans et sp.

The Sparganium Zone — Fringing the northerly border of the
cove, but in other respects like the Pontederia zone which
fringes its western border, we find the next distinctly marked
type of vegetation, which is an almost pure stand of Sparganium
eurycarpum.

The Typha Zone — Inside of the fringe of Sparganium just
mentioned, and extending in all directions until it encounters
regions seized by Phragmites, lies the clear-cut cattail habitat.

96

The Ohio Journal of Science [Vol. XVI, No. 3,

Like the last several zones mentioned, it has a bottom rich
in humus, while the water ranges from six to twelve inches
(1.0 to 3 decimetres) in depth. Typha latifoUa grows here to
the practical exclusion of everything else, save for an occasional
space which may be called —

The Spirodela Habitat — These spaces are usually a couple
of yards or more (1 to 2 metres) in diameter, and are open
areas of water rather closely hedged in by Typha, with occasional
straggling plants of Sparganium. The water here is, of course,
quiet and usually about three to six inches (.7 to 1.5 decimetres)
in depth, richly strewn with colonies of Spirodela polyrhiza and
Lemna trisulca, principally the former.

The Castalia Station

Jan., 1916]

Evaporation and Plant Zones

97

On June 29th an instrument was set up in each of the
zones indicated and daily morning readings taken, with the
exceptions and interruptions shown in the table, until July 22nd,
when the last readings were made. The corrected totals given
in the table are for the actual number of days during which
every instrument was in working condition. It may be fairly
asserted that this period covers, in spite of its shortness, a
critical time of year for vegetation so far as actual transpiration
is concerned. It will also be noted in the table that all figures-
have been reduced to a percentage basis, using the lowest total
as 100%.

Table Showing Daily Water Loss From Each Instrument During Time of

Experiment.

Abbreviations for Stations as on Map, Fig. 3.

S

D

C

C

P

P

Pn

Cs

Sp

Ty

Ty

Sd

UPPER

UPPER

UPPER

June

29

25

26

10

19

3

29

9

7

18

30

14

15

11

11

6

21

12

6

15

July

1

21

24

13

19

13

44

19

18

18

2

10

6

4

5

3

12

8

5

7

3

35

17

17

9

13

11

14

26

12

14

9

13

4

19

10

9

4

12

5

12

17

8

10

7

9

5

35

17

17

11

9

8

7

28

11

13

8

12

6

36

18

18

7

18

14

18

28

15

14

9

14

7

28

11

12

6

4

8

11

27

10

11

8

10

8

53

10

22

10

18

14

11

42

21

25

16

19

9

34

16

18

7

14

10

14

29

15

15

9

14

10

39

14

18

7

18

10

15

30

13

15

10

13

11

27

23

12

12

13

15

44

16

20

15

20

12

15

13

6

14

7

9

30

12

11

7

13

13

16

20

10

17

13

16

35

16

22

5

13

14

13

12

7

11

10

7

18

10

17

7

9

15

3

4

2

1

1

3

2

1

0

2

16

12

15

5

15

10

8

24

9

15

8

10

17

38

17

16

9

15

8

7

40

11

16

11

13

18

67

27

23

19

27

16

15

53

18

25

9

26

19

62

28

19

13

32

16

16

47

21

27

14

23

20

49

19

19

13

16

15

10

41

13

18

11

18

21

51

23

26

16

25

15

16

45

14

23

14

18

22

48

14

25

12

26

16

16

14

20

10

17

Net

Total

546

233

234

132

221

150

166

453

182

226

135

202

Per

c'tage

413

176

175

100

167

113

125

343

137

171

102

153

98

The Ohio Journal of Science [Vol. XVI, No. 3,

Standardized porous cups mounted as shown over ordinary
100 CO. graduates, with curved tubes for equaHzing the air
pressure, were used. When set at ground or water-level, this
gave a means of measuring the drying power of the air at
11-14 inches (2.7-3.5 decimetres) up.

At each station (see map, Fig. 3) an instrument was set
at this lowest possible level. At the Scirpus station an anchored
raft was utilized, to which the evaporimeter was stoutly lashed,
while at the other stations the instruments were fastened
to firmly set cypress stakes. In the Calamagrostis, Phragmites,
and Typha zones the stakes were of sufficient height to allow
the location of a second instrument approximately four feet.
(1.5 metres) above the first.

Composite Profile Showing Evaporation Percentages.

All readings were taken by myself to eliminate error due
to personal equation, and were taken from the bottom of the
meniscus. So often as necessary the graduates were carefully
refilled to the 100 cc. mark.

That the profile. Fig. 5, is a composite is readily seen from
the zone map, but it has been chosen as affording the most
graphic means at hand of setting forth at the same time the
majority of relative habitat conditions and the evaporation
percentages obtained. The profile will be better understood
if it is borne in mind that the left-hand side represents the
quarter from which the prevailing winds come, and that during
the days for which the corrected totals were figured the actual
wind movement from that quarter was 202 miles in excess of
.that from the opposing quarter,^ which moreover is strongly
sheltered by Cedar Point itself.

Jan., 1916] Evaporation and Plant Zones 99

The Scirpiis zone, with its maximum exposure to wind
and Hght, shows the highest rate by far — 413%. It seems
not improbable that to survive in such an environment the
Scirpus must possess unique characters beyond its undoubted
abihty to withstand the heavy beating of surf, which Jennings^
mentions.

The zone characterized by Castalia and Potamogeton ranks
second, with an evaporation percentage of 343. While not
directly exposed to severe winds this zone is undoubtedly one
of rather free air movement, and certainly one of continual
and merciless exposure to the sun. The relatively high rate
of evaporation here may well be the factor that is prohibitive
of emersed forms, other than stray plants of Scirpus, although
the factor of water depth cannot be ignored.

That this habitat is a rigorous one for plant life is further
shown by the fatal effects of a day's exposure of the under side
of a Castalia leaf to the air of its habitat, whether by a con-
tinued light breeze from the proper quarter, or by accident or
experiment. This phenomenon, which it is interesting to
compare with "wind-burning" as noted by Gates, ^"^ was fre-
quently observed during the course of the work here described.

Dianthera is a plant characteristic of washed sand bottoms,^
a condition implying more or less exposure, and in this marsh
it is found under conditions of evaporation distinctly com-
parable with those obtaining in the windswept tops of Cal-
amagrostis, at an elevation of five feet (1.5 metres).

The remaining figures are chiefly valuable as showing rather
strikingly the modifying power of vegetation on evaporation.
Especially marked is the difference between the nearby instru-
ments in the Spirodela and Typlia zones, respectively, at the
same level. Likewise the waterless is much greater at the same
level in the case of low-growing than of high-growing vegetation.
Moreover the instrument standing in the compact and sheltered
lower layers of the Calamagrostis lost decidedly less than the
one in the leafless and wide spaced lower layers of Phragmites.

Finally the differences between upper and lower stations
in Calamagrostis, Phragmites and Typha respectively, are
ample enough to confirm Yapp's observation^ that different
strata of marsh vegetation afford vastly different habitat
conditions, as regards the evaporational factors. This is
not the less true because none of the three zones mentioned
happen to show any distinct stratification.

100 The Ohio Journal of Science [Vol. XVI, No. 3,

Summary and Conclusions — Transpiration loss, so far as
measured by the evaporating power of the air, is definitely
correlated with physical exposure and zonal distribution of
plants in the marsh studied.

Topography, substratum, direction of prevailing wind, and
thickness of vegetative cover all find logical expression in the
evaporation percentages obtained.

Evaporation must be assigned an important role coordinate
with such fundamental factors as water depth and organic
content of substratum in interpreting the plant distribution in
the marsh under examination.

The writer feels under considerable obligation to Dr.
Raymond J. Pool, of the University of Nebraska, Dr. E. N.
Transeau of Ohio State University, and to the staff of the Ohio
State Lake Laboratory for courtesies and suggestions during
the course of the work and the writing of the paper presented
above.

Bibliography.

1. Yapp. On Stratification in the Vegetation of a Marsh, etc. Ann. Bot.

23: 275-323. 1909.

2. Transeau. Plant Societies and Evaporation. Bot. Gaz. 45: 217-231. 1908.
Apparatus for Study of Comparative Transpiration. Bot. Gaz. 52: 54-60. 1911.

3. Livingston. Operation of the Porous Cup Atmometer. PI. World 13:

111-119. 1910.

4. Weaver. Evaporation and Plant Successions in Southeastern Idaho. PI.

World 17: 27.3-300. 1914.

5. Fuller. Evaporation and Plant Succession. Bot. Gaz. 52: 193-208. 1911.

6. Mosely. Formation of Sandusky Bay and Cedar Point. Proc. Ohio Acad.

Sc. 13 An. Kept. 4: 179-2.38. 1905.

7. Jennings. Vegetation of Cedar Point. Ohio Nat. 8: 291-3.39. 1908.

8. Ohio State University Bulletin, November, 1914.

9. Records of U. S. Weather Bureau Office. Sandusky, Ohio.

10. Gates. Wind Burn in Amorphophallus. Bot. Gaz. 60: 414. 1915.

A METHOD FOR THE RENEWAL OF PLANT NUTRIENTS

IN SAND CULTURES.

A. G. McCall.

The recent publications of Tottingham''' and of Shivef have
suggested the desirabihty and importance of having some
method by which the effect of different nutrient solutions upon
plant growth might be studied in the presence of some solid
substance similar to the soil, but at the same time furnishing
fewer chemical and biological complications. Acting upon this
suggestion the writer has devised a method by which seedling
may be grown in sand and the nutrient solution renewed or
modified almost as readily as in water cultures. In duplicating
in sand some of Shive's w^ork with wheat seedlings in solution
cultures, use was made of graniteware pots approximately
12 X 12 centimeters inside, tapering slightly at the base and
having a wide projecting rim at the top and a capacity of 1500
grams of dry quartz sand when filled to within about three
centimeters of the top. To provide for the removal of the
solution a small lead tube was soldered into the side as near the
bottom as possible. The soldered joint and the lead tube was
covered with paraffin to guard against lead poisoning and the
outlet closed by means of a short length of rubber tubing pro-
vided with a pinch cock. The description of the method given
in the following paragraphs includes the details of manipulations
from the starting of the seedlings to the harvesting of the
plants. The seed is soaked in water and the seedlings grown in
the manner described by Tottingham|, to a height of about
three or four centimeters, when they are ready to be transferred
to the sand cultures. While the seed is being germinated 1500
grams of dry quartz sand (previously washed several times with
distilled water) is weighed into the pot, the outlet at the bottom
of the pot being screened on the inside by means of a plug of
glass wool inserted before the pot is filled. With the pinch cock
closed distilled water is now added to the pot until the sand is
completely saturated, after which the pinch cock is opened and
the surplus water is allowed to drain out through the tube at

*A Qualitative Chemical and Physiological Study of Nutrient Solutions for
Plant Cultures. Physiological Researches Vol. I, No. 4, May, 1914.

fA Three-Salt Nutrient Solution for Plants. Amer. Journal of Botany,
4:157-160, April 1915.

JTottingham. p. 176.

lOI

102

The Ohio Journal of Science [Vol. XVI, No. 3,

the bottom of the pot until the last free water has disappeared
from the surface of the sand. A hemispherical clay funnel is
placed in position as shown in the photograph and the pot is
ready to receive the seedlings. After careful selection for uni-
formity, the seedlings, six in number, are planted equal dis-
tances apart on a circle drawn midway between the edge of the
funnel and the wall of the pot. Care is taken to have the

Fig. 1. Granite-ware pots for the study of plant nutrients in sand cultures.

seedlings at such depth that the top of the grain is just level
with the surface of the sand. After all of the seedlings are in
place the pinch cock is closed and the pot is tapped gently on
the top of the table until free water appears on the surface of
the sand. This manipulation serves to pack the sand around the
roots of the seedlings and at the same time to level off the surface
of the sand preparatory to putting on the seal of Briggs and
Shantz'-"' wax.

"Bui. No. 230, Bureau of Plant Industry, U. S. D. A., p. 13.

Jan., 1916] Renewal of Plant Nutrients 103

The surplus water is then drawn out of the pot by appH-
cation of suction (by means of an aspirator) to the tube at
the bottom and a thin layer of the melted wax is flowed over
the surface, completely covering the surface of the sand between
the funnel and the wall of the pot. Care should be taken not
to have the wax too hot otherwise the seedlings may be injured
at the point of contact between the wax and the plant. The
surface must be sealed to prevent loss of water by evaporation
from the surface of the sand and of course the walls of the pot
must be impervious to moisture in order that transpiration can
be measured and the concentration of the nutrient solution
controlled. The pot is now ready to receive the nutrient solu-
tion, which is added through the funnel at the top while the
water is being removed at the bottom by the application of
suction to the outlet tube. A double or triple portion of the
nutrient solution is passed through the sand at this first appli-
cation in order to flush out the distilled water. The pot is now
placed on the scales and the removal of solution is continued
until the sand has been reduced to the desired moisture content
which should be as near the optimum as possible. At the end of
each three-day period the pot is weighed and sufficient water is
added through the funnel to bring the system back to its
original weight. A fresh nutrient solution is now added in the
desired amount (250 cc. for pots of this size) , while an equivalent
amount of solution is removed at the bottom. A nutrient
solution of the same concentration may be used throughout the
entire growth period or it may be varied from time to time as
the plants continue to develop.

The plants may be harvested at any time by removing the
wax seal and cutting off the plants level with the surface of
sand and, if desired, the roots may be recovered from the sand
by washing them out with a jet of water. The weight records
will give the transpiration of each culture and the harvest
records can be made to include the dry weights of both tops and
roots. This method also furnished a means by which the
original concentration of the solution can be compared with its
concentration after contact with the soil and with the plant
roots. The method is superior in many ways to water cultures
because it permits the plants to be grown under conditions that
approximate those found in the field, so far as the sub stratum
is concerned, and it seems probable that with some slight modi-
fications which are now in progress it will be possible to apply
the method to cultures grown in sandy and sandy loam soils.

Department of Agronomy, Ohio State University.

ADDITIONS TO THE CATALOG OF OHIO VASCULAR

PLANTS FOR 1915.

John H. Schaffner.

The following species have been added to the list of Ohio
Plants. The numbers refer to the list as originally published
or are additions of new species inserted at the proper places.

53.1 Equisetum kansanum Schaffner. Kansas Horsetail.
Massillon, Stark County. Collected 1906. L. S.
Hopkins.
68. Pinus strobus L. White Pine. Raven Rocks, Belmont
County. An isolated group near the Monroe County
line. Emma E. Laughlin.

158. Stenophyllus capillaris (L.) Britt. Hair-like Steno-
phyllus. Kent, Portage County. L. S. Hopkins.

216.1 Carex suberecta (Olney) Britt. Prairie Straw Sedge.
Brush Lake, Champaign County. John H. Schaffner
and Fred J. Taylor.

324. Poa debilis Torr. Weak Spear-grass. Phalanx, Trum-
bull County. Almon N. Rood.

419. Panicum agrostoides Spreng. Agrostis-like Panic-grass.
Kent, Portage County. L. S. Hopkins.

427. Panicum philadelphicum Bernh. Philadelphia Panic-
grass. Phalanx, Trumbull County. Almon N. Rood.

595. Liparis liliifolia (L.) Rich. Large Tway-blade. Ironton,
Lawrence County. Lillian E. Humphrey.

601. Corallorrhiza wisteriana Conrad. Wister's Coral-root.
Berrysville, Highland County. Katie M. Roads.

770.1 Oxalis acetosella L. White Wood-sorrel. Raven Rocks,
Belmont County. Emma E. Laughlin.

875.1 Viola cucullata Ait. Marsh Blue Violet. Parma Town-
ship, Cuyahoga County. E. L. Fullmer.

1118. Trifolium reflexum L. Buffalo Clover. AUedonia, Bel-
mont County. Emma E. Laughlin.

1559. Agalinis skinneriana (Wood) Britt. Skinner's Gerardia.
White-flowered form. Southeastern part of Fulton
County. J. S. Hine.

1786. Triosteum angustifolium L. Yellow Horse-gentian.
Ironton, Lawrence County. Lillian E. Humphrey.

104

PLANT DISEASE EXHIBIT CASES.*

Leo E. Melchers.

Recently the writer had occasion to prepare various sets
•of plant disease exhibit frames or cases for county and state
fair exhibition purposes. Numerous types of trays, boxes
and frames of various shapes and sizes have been given a trial
by the writer, but the type to be described in this article,
appears to be the most practical and serviceable for exhibiting
specimens other than those which must be preserved in jars.
In order to meet the requirements which are essentially neces-
sary for an attractive, but still serviceable plant disease exhibit
case, the following things must be taken into consideration:

1. The exhibit must withstand rough handling in shipping
or otherwise.

2. The size of the shipping boxes or trunks in which the
cases are packed, must comply with the compulsory regulations
of railroad companies, if one wishes to take them along as
baggage. Boxes or trunks beyond a certain length will not
be accepted by railroad companies.

3. One person should be able to handle these frames
without difficulty.

4. They should be constructed of light material, but still
they must be durable.

5. Glass should be avoided on account of its fragility and
weight. Celluloid is more satisfactory.

6. The frames should be constructed so as to withstand
stacking in a box or trunk when shipping from place to place.

7. The case should be of a size which will accomodate two
types of specimens: (1) entire cereal plants; and (2) fragments
of plants, such as leaves affected with spots, cankers on limbs
or twigs, etc.

8. They should be deep enough to accomodate such
pathological specimens as cankers on limbs; but, on the other
hand, so designed that they will satisfactorily accomodate
■cereals, leaves, etc.

9. They must appear neat and attractive.

10. The cost of construction should be reasonable.

"Kansas State Agricultural College, Manhattan, Kansas.

105

106

The Ohio Jounial of Science [Vol. XVI, No. 3,

In order to meet the above requirements, the writer
attempted to construct a case which is not expensive, yet
attractive and well designed to display plant diseases to the
best advantage.

A working plan of this case is shown on Fig. 3. The outside
measurements of the case are 24" x 40," the inside measurements.
being 223/2" ^ 383^". The sizes of the two kinds of partitions

Fig. 1. Exhibit case showing specimens of two sizes.
(Photo by L. E. Melchers.)

are 9}4" x 11" for the smaller, and 11" x 19" for the larger.
The arrangement of the partitions may be changed to meet
the requirements. Besides the arrangement as illustrated,
either eight compartments 93^2" ^ H". or four 19" x 11", may be
made. The 19" x 11" size is best adapted for such specimens as
cereals, weeds, etc., while the smaller are sufficiently adequate
for the majority of pathological specimens, such as cankers,,
leaf-spot diseases, etc. See Fig. 1.

Jan., 1916]

Plant Disease Exhibit Cases

107

Fig. 2 illustrates a frame of similar construction, but
designed for displaying photographs. The trays is only one-
half inch deep. A quarter-inch, quarter-round molding is
used to hold the celluloid and cardboard mounting in place.
The crosspieces are likewise quarter-inch, quarter-round strips.
The celluloid protects the photographs, and may be wiped off
with a damp cloth without injury to itself or photographs.

Fig. 2. Exhibit case showing arrangement for photographs.
(Photo by L. E. Melchers.)

Preparation of Material for Exhibit Case.

Various types of plant disease material may be placed in a
case of this design. Most of the specimens shown in the
accompanying illustration were dried and pressed. These were
glued on, and fastened by means of tape to three-ply white
cardboard, of the proper dimensions, in the ordinary manner.
Where bulky specimens, such as raspberry canes, Kafir heads^
etc., were used, fine wire was employed.

108

The Ohio Journal of Science [Vol. XVI, No. 3,

The writer finds that Riker specimen mounts, 63.4" x 834"
or larger, are well adapted for some purposes in connection
with these canes.

Cankers of fruit trees, plaster-cast specimens, fragile speci-
mens, or specimens contained in glass tubes, are completely-
protected and kept intact, if first put into one of these mounts,
and then placed into one of the compartments. If Riker
mounts are used, they must be fastened into place inside the

Fig. 3. A working plan for a plant disease exhibit case.

compartment, by nailing blocks of wood, as braces, up against
the sides of the Riker mount. The nails are driven through
these blocks and into the bottom of the frame. The wooden
blocks act merely as braces to prevent the mount from shifting
in the compartment.

The different specimens will naturally vary in thickness.
The mounted specimens should be in close contact with the
celluloid. In order to attain this, cotton is used to fill up the
difference in depth between the thickness of the specimen and
the depth of the compartment. Where Riker mounts are

Jan., 19 IG] Ohio Academy of Science 109'

employed, the blocks and intervening spaces are covered
and filled with cotton. After the mounted specimens are
placed into their respective compartments, the celluloid should
be placed over one-half of the frame. The sheets of celluloid
comes in sheets 20" x 50". One sheet will cover the entire
frame, but necessarily in two pieces, allowance being made for
overlapping at the center crosspieces and fastening to the edges
of the frame. (See working plan). For the specimen cases,
oak strips 3/16" x 5/16" are employed to fasten the celluloid in
place, these being a part of the frame. The other strips for the
cross-partitions are Y/ wide. These strips are fastened with
small screws, (counter sunk), which pass through the celluloid
and into the frame proper.

The weight of one of the specimen cases when completed
and containing the specimens, is about 13 pounds. The total
cost is approximately $2.50.

The Material Necessary for the Construction of One of the Specimen Cases:

Oak,

16' X K" X Yi"

Cypress,

8' X y2" X 1"

12' X \"x%"

12'xi^"x 6"

2'xi^"x 4"

CeUuloid,

20" X 50" (10/1000" thick)

Screws,

32, gun-metal, flat-headed, %"

OHIO ACADEMY OF SCIENCE.

QUARTER-CENTENNIAL ANNIVERSARY.

The Twenty-fifth Annual Meeting of the Ohio Academy of
Science was held at the Ohio State University, Columbus, on
Friday and Saturday, November 26 and 27, 1915, under the
presidency of Professor J. Warren Smith, of Columbus.

Owing to the anniversary character of the meeting, the usual
program of volunteer papers was replaced by a series of invited
addresses, as follows:

Presidential Address — Agricultural Meteorology, Professor J.

Warren Smith, United States Weather Bureau, Columbus.
Address — Applied Meteorology and the Work of the Weather

Bureau, Doctor Charles F. Marvin, Chief United States Weather

Bureau, Washington, D. C.

no The Ohio Journal of Science [Vol. XVI, No. 3,

Address — The Relation of the Academy to the vState and to the
People of the State, Dr. T. C. Mendenhall, Ravenna.

Historical Sketch of the Ohio Academy of Science, Professor
William R. Lazenby, Ohio State University, Columbus.

Reviews of Scientific Progress in the Quarter Century.

Geology, Professor Frank Carney, Denison University, Granville.

Botany, Professor Bruce Fink, Miami University, Oxford.

Physics, Professor Frank P. Whitman, Western Reserve University,

Cleveland.
Zoology, Professor Edward L. Rice, Ohio Wesleyan University,

Delaware.
Chemistry, Professor William McPherson, Ohio State University,

Columbus.
Archaeology, Professor G. Frederick Wright, Oberlin College, Oberlin.

At the supper, held Friday evening at the Ohio Union, short
addresses were given by visiting delegates from other scientific
societies. Governor Willis had expected to be present and to
speak, but was unavoidably prevented at the last moment.

Notice was received of the appointment of the following
delegates. Those marked with the asterisk were present at the
meeting.

American Association for the Advancement of Science — ^Professor L.O.
Howard, Washington, D. C.

Boston Society of Natural History — ^Professor Frederick C. Waite,
Cleveland, Ohio.

CJiicago Academy of Science — Doctor Frank C. Baker, Chicago, 111.

Indiana Academv of Science — *Doctor D. W. Dennis, Richmond,
Ind.; Mr. E. B. Williamson, Bluffton, Ind.

Iowa Academy of Science — *Professor Herbert Osborn, Columbus,
Ohio; Doctor Charles R. Keys, Des Moines, Iowa.

New York Academy of Science — Mr. Emerson McMillin, New York
City; Professor H. P. Gushing, Cleveland, Ohio.

Academy of Natural Sciences of Philadelphia — Doctor Howard
Ayers, Cincinnati, Ohio.

Washington Academy of Sciences — ^Professor Dayton C. Miller,
Cleveland, Ohio; *Doctor Charles F. Marvin, Washington, D. C.

Cincinnati Section of the American Chemical Society — ^Doctor Lauder
W. Jones, Cincinnati, Ohio; Doctor Alfred Springer, Cincinnati, Ohio.

Cincinnati Society of Natural History — Doctor DeLisle Stewart,
Cincinnati, Ohio.

Columbus Audobon Society — * Professor J. C. Ilambleton, Columbus,
Ohio; Miss Lucy Stone, Columbus, Ohio.

Denison Scientific Association — *Doctor George Fitch McKibben,
Granville, Ohio; *Mr. Charles W. Henderson, Granville, Ohio.

Jan., 1916] Ohio Academy of Science 111

Wooster University Scientific Club — *Mr. Frank H. McCombs,
Wooster, Ohio.

The Cuvier Press Club — -Mr. James W. Faulkner, Cincinnati, Ohio.

Association of Ohio Teachers of Mathematics and Science — *Professor
S. E. Rasor, Columbus, Ohio.

Ohio State University Scientific Association — Professor Karl D.
Swartzel, Columbus, Ohio; *Professor James R. Withrow, Columbus,
Ohio.

Oxford Science Club — ^Professor J. A. Culler, Oxford, Ohio.

Otterbein Science Club — *Mr. Richard M. Bradfield, Westerville,
Ohio.

Baldii'in-Wallace Science Seminar — ^Professor E. L. Fullmer, Berea,
Ohio.

The following members of the old Tyndall Association, so
potent in the scientific life of Columbus and Ohio in the Seventies
and Eighties, were also present by special invitation:

Mr. H. N. P. Dole, Columbus, Ohio.
Mr. Martin Hensel, Columbus, Ohio.
Mr. Curtis C. Howard, Columbus, Ohio.
Professor William R. Lazenby, Columbus, Ohio.
Doctor C. L. Mees, Terre Haute, Ind.
Doctor T. C. Mendenhall, Ravenna, Ohio.
Doctor Sidney A. Norton, Columbus, Ohio.
Mr. D. E. WilHams, Columbus, Ohio.

In the business session the most notable action was the
adoption of a constitutional amendment, suggested at the
previous annual meeting, by which the date of the annual
meeting is changed from Thanksgiving to March or April, the
exact date to be fixed by the Executive Committee. By vote
of the Academy the next meeting will be held in the spring of
1916.

The Trustees of the Research Fund announced a further
gift by Mr. Emerson McMillin, of New York, of $250.00 for the
encouragement of the research work of the Academy.

As a result of the suggestions contained in the address by
Dr. Mendenhall, on The Relation of the Academy to the State
and to the People of the State, a Committee on Legislation was
appointed, consisting of Dr. T. C. Mendenhall, Chairman,
Prof. F. C. Waite and Prof. Herbert Osborn.

The previous affiliation of the Academy with the Ohio
Journal of Science was continued with minor modifications;
but the incoming president was instructed to appoint a com-

112 The Ohio Journal of Science [Vol. XVI, No. 3,

mittee to confer with the Committee on Legislation as to
possibilities of obtaining funds for publication, the Committee
to report back to the Academy at its next annual meeting.
President Hubbard appointed Prof. J. Warren Smith, Chair-
man; Prof. Frank Carney, Prof. F. C. Waite, Prof. J. S. Hine
and Prof. C. G. Shatzer,

Forty-one new members were elected at the meeting.

The officers and standing committees for 1915-1916 will be
as follows :

President — Prof. G. D. Hubbard, Oberlin College.

Vice-President for Zoology — Prof. F. L. Landacre, Ohio State
University.

Vice-President for Botany — Prof. M. E. Stickney, Denison
Univeristy.

Vice-President for Geology — Prof. T. M. Hills, Ohio State
University.

Vice-President for Physics — Prof. L. T. More, University of
Cincinnati.

Secretary — Prof. E. L. Rice, Ohio Wesleyan University.

Treasurer — Prof. J. S. Hine, Ohio State University.

Executive Committee, together ivith the President, Secretary and
Treasurer, members ex-officio — Prof. L. B. Walton, Kenyon
College; Prof. C. G. Shatzer, Wittenberg College.

Trustees of Research Fund — Prof. W. R. Lazenby, Ohio State
University; Prof. M. M. Metcalf, Oberhn CoUege; Prof. N. M.
Fenneman, University of Cincinnati.

Publication Committee — Prof. J. H. Schaffner, Ohio State
University; Prof. C. H. Lake, Hamilton; Prof. L. B. Walton,
Kenyon College.

Library Committee — Prof. W. C. Mills, Ohio State University;
Prof. F. O. Grover, Oberlin College; Prof. J. A. Culler, Miami
University.

Edward L. Rice, Secretary.

Delaware, Ohio, December 15, 1915.
Date of Publication, January 18, 1916.

THE

Ohio Journal of Science

PUBLISHED BY THE

Ohio State University Scientific Society
Volume XVI FEBRUARY, 1916 No. 4

TABLE OF CONTENTS

Sheard and Morris — The Spectra of Some Halogen Compounds and Phe-
nomena Connected Therewith 113

Krecker — Sunfish Nests of Reimiller's Cove 125

BoHANNAN — Hexagon Notation 135

IvAMB — Outliers of the Maxville Limestone in Ohio North of the Licking River 151
Napper— Occurrence of Carbonaceous Material in the Greenfield Member of

the Monroe Formation. 155

THE SPECTRA OF SOME HALOGEN COMPOUNDS AND
PHENOMENA CONNECTED THEREWITH.*

Charles Sheard and C. S. Morris.

A careful search of the literature on the spectra of com-
pounds reveals but few papers of any importance. The first
of these is by B. O. Peirce on the "Emission Spectra of Halogen
Compounds of Mercury" in the Annalen der Physik, N. F.
Vol. 6, 1879. His investigations were carried out using Geissler
tubes excited by an induction coil; the tubes with the con-
tained salt were heated by a Bunsen burner. With mercuric
and mercurous chlorides he found a band lying between the
yellow and the green mercury lines and observed that in the
green region the continuous spectrum was filled with many
fine, weak lines. The conclusion is drawn that the emission
spectra of the two chlorides of mercury under heat are the
same, due to the fact that the mercurous chloride dissociates
into mercuric chloride and chlorine and the continuous spectrum
is therefore due in both cases to the mercuric chloride. The
iodide, bromide and chloride compounds of mercury gave
continuous bands with their middle points at about 4430,
5000 and 5800 Angstroms respectively.

*Read before the American Physical Society, December, 1915.

113

114 The Ohio Journal of Science [Vol. XVI, No. 4,

In 1S97 A. C. Jones published an article (Ann. der Phy.
N. E. Vol. ()2, page 31) in which he confirmed the results
obtained by Peirce and extended the investigations on the
bands into the ultraviolet region.

The latest research on the subject is by A. H. Chapman
(Physical Review, Second Series, Vol. IV, 1914), who used
mercuric iodide, ferric iodide and stannic iodide. In a gen-
eralized conclusion he says "that a wide emission band
shading off towards the violet and the red is characteristic
of the compounds investigated, and that when the absorption
spectrum of the compound is available, there seems to be a
definite relation existing between the absorption and emission
bands. It would seem therefore that the vibrating system
responsible for the emission is also effective in producing
absorption in solution."

It is the purpose of the investigations here reported upon
to extend our present knowledge of the emission spectra of
compounds and to determine, if possible, something concerning
the nature and structure of the vibrating system or systems
responsible for the spectra. It was also hoped to make some
comparisons between the emission and absorption spectra
of the vapors with certain of the compounds used, but in this
latter proposition little success has come. There have arisen,
however, in connection with these latter investigations some
very interesting phenomena which have either thrown some
light on the main problem in hand or furnished a basis for
some suggestions as to the nature of the thermions from heated
salts.

APPARATUS.

The upper electrode of the apparatus used for examining
emission spectra was a brass tube about seven-eights inch in
diameter and three inches long, the lower one being a brass
tube about three-quarters inch in diameter and eight inches
long, with one end tightly sealed with a brass plug. A water
cooling jacket was constructed around the upper end of the
lower electrode; this served as a screen to prevent direct contact
of the gas flame with the rest of the apparatus and, operating
as a cooler, preserved the waxed joints and corks. The two
metal tubes were connected by a piece of heavy capillary
tubing of about 1.3 mm. inside bore. Capillary tubes of

Feb., 1916] Spectra of Some Halogen Compounds 115

somewhat larger diameter were tried but discarded since the
current density of the discharge was not sufficiently great to
give an intense spectrum. Too small capillaries could not be
used because they readily plugged up with vaporized salt.
Rubber stoppers connected the capillary with the remaining
parts of the tube.

The form of apparatus used in the attempts made to investi-
gate the absorption spectra of the vapors is discussed later in
this paper.

RESULTS.

A Geryck two-cylinder pump was connected to the spectrum
tube and a low pressure, varying in different experiments from
1 cm. to 0.1 mm. mercury pressure, maintained. The dis-
charge from the induction coil was then started and without
heating the tube the spectrum was examined for lines due to the
elements of the compound. In some instances there appeared
nothing but the air spectrum,* but in a few cases, as zinc
and mercuric iodide, some lines of the elements appeared,
indicating that the compound dissociated a little at ordinary
temperatures under low pressure. As soon, however, as a
little heat was applied the air spectrum began to disappear and a
spectrum peculiar to the compound appeared. This remained
for some minutes, varying with the compound used, but in
general, if further heating was discontinued the air spectrum
gradually returned and replaced the spectrum of the com-
pound; this process could be repeated until finally the lower
half of the electrode would become red hot without any spectrum
of the compound being in evidence. But if the heating of the
tube was carried on rapidly the air spectrum was quickly
replaced by lines characteristic of the elements of the com-
pound, which in turn gave way to a continuous region or regions
with a few lines peculiar to the members of the compound
surviving. After heating for some time (usually fifteen to
thirty minutes) the spectrum of the compound and its elements
was rather quickly replaced by the air spectrum. These
changes were so rapid, photographically considered, that few
spectrograms have been obtained. The continuous regions

*A careful study was made of the spectrum given by the empty tube both
when cold and when heated. Under both conditions a large number of bands,
diffuse toward the violet, were found in the region 4861 to 4142 t. m. and are due
to nitrogen. Some lines and narrow bands were measured in the red-yellow
region, but thus far it has been impossible to identify them.

(1
u i( a

li u u

IIG The Ohio Journal of Science [Vol. XVI, No. 4,

or bands found in the spectra of the compounds studied are
indicated in the following data. The pressure in nearly every
case was about 2 mm. of mercury, but it was discovered that a
considerable range of pressure (from 0.5 to 10 mms. mercury)
had little effect upon the results.

I. Iodides.

Calcium Iodide.

BANDS REMARKS

'6075-5845 (.•') Seemingly continuous but uncertain.

5615-5528 Fairly sharp on red side, diffuse at blue.

5180-5100

4830-4787

4507-4465 " " " " " " "

4438-4375 (?) Apparently continuous, but uncertain.

Mercuric Iodide.

BANDS REMARKS

6072-5845 Sharp towards red, diffuse towards violet.

5605-5535

5195-5132

4828-4788

4506^470 More or less diffuse at both ends.

4450-4375

A few prominent lines were measured and identified as
follows: 6563 and 4861 due to hydrogen and 5790, 5769, 5461,
4916 and 4358 due to mercury. These lines were present at
all stages of operation of the tube. A considerable number of
iodine lines made their appearance on first heating the tube.

Zi)ic Iodide.

Upon the first heating of the zinc iodide the following
simple line spectrum of zinc and iodine was obtained; 5781,
5766 and 5448 of iodine, 5182 and 4912 of zinc and in addition
6563 of hydrogen and 4358 of mercury.

With rather low heat the following bands were obtained:
.5610-5535; 5195-5116 and 4829-4780. All of these were
fairly sharp towards the red and diffuse toward the violet end.
A number of sharp lines were also present at this stage of the
experiment and a majority of these were measured; 6363,
5894, 4810, 4722, 4680 due to zinc; 6131, 6076, 5961, 5739,
5696, 5628, 5165, 4667, 4645, 4635 due to iodine and the fol-
lowing lines which have thus far not been identified — 6235,
6203, 6027, 5937, 5839, 5816, 5119.

Feb., 1916] Spectra of Some Ilalogefi Compounds 117

Cadmium Iodide.

Heat was applied slowly; numerous spectral lines appeared
together with what we concluded to be the same three bands
as found in zinc iodide, but as heat was applied the compound
quickly ceased to function — due doubtless to rapid vaporiza-
tion— and the air spectrum returned so quickly with each
increase of temperature up to the highest degree attainable
that no measurements could be made.

II. Chlorides.

Fused Stannic Chloride.

Low heat gave a continuous region from 5800 to 4400
diffuse at both ends. The following lines were noted when the
salt was first heated: 6453, 5799, 5631, 5588, 5563, 5333 and
4525, due to tin and 5460 due to chlorine.

It was found on the initial heating that the tin lines appeared
very prominent when the pressure was of the order of a centi-
meter of mercury, but that these lines disappeared in general
and the continuous spectrum named above appeared as the
pressure was reduced. With further experimentation this
pressure effect disappeared for reasons which will be suggested
in the concluding portions of this paper.

Ferric Chloride.

The continuous region, 5900-4800 Angstroms, was not
sharply defined at either limit.

It was difficult to get a discharge to pass through the
tube containing the ferric chloride when it was heated. The
capillary filled readily with a brownish liquid which over-
flowed the ends of the rubber cork stoppers and operated to form
a conducting layer along the surface.

After the disappearance of the air spectrum the character-
istic yellow and green lines of mercury and the red and blue
lines of hydrogen appeared.* With further heating a con-
tinuous region, indeterminate at both ends, occurred from
approximately 4800 to 5900. There was no evidence of any
iron lines at any period of the experimentation.

*Mercury vapor and hydrogen were present as "impurities" in all these
experiments, the mercury coming from the McLeod guage used to measure
pressures.

118 The Ohio Journal of Science [Vol. XVI, No. 4,

Manganous Chloride.

Low heat gave a continuous region from 5900 to 4450,
diffuse at both ends.

The prominent Hnes were identified as manganese 6017,
4822, 4783 and 4754, in addition to three or four hnes belonging
to hydrogen and mercury. The spectral examination showed
the presence of the base of the compoimd only; no lines due
to chlorine were detected.

III. Bromides.

Calcium Bromide.

Low heat gave a continuous region, 5500 to 4850, shading
off at each end.

After the discharge had passed for a little time, but before
heating the apparatus, the lines present were measured and
identified as those of hydrogen and mercury. This indicates
that practically none, if any, of the calcium bromide vaporized
and dissociated under low pressure at room temperature.

Mercurous Bromide.
Strong heating gave a continuous region from 5072 to 4912.

Zinc Bromide.

With excessive heating there was obtained a continuous
region from 5550 to 5055, neither limit being sharply defined.
With the bottom of the lower electrode red hot there was a
small, but very intense continuous band, about 100 Angstroms
wide, with its center at about 5055, together with a region,
much less luminous, which appeared to be continuous from
5550 to 5150.

ABSORPTION SPECTRA OF THE VAPORS.

Chapman (Phys. Rev. 2nd Series, Vol. IV, p. 28, 1914)
came to the conclusion that the vibrating system giving the
emission spectra of the compounds was also potent in producing
absorption in solutions. It is reasonable to suppose that the
vibrating system might also persist and preserve its identity
in the vaporous state and that the absorption spectrum of the
compound should be the complement of the emission spectrum.
Several attempts were made to see if such were the case. A
tube was constructed, 22 inches in length, with an inside
diameter of 1}/^ inches. The ends were provided with jackets
for water cooling. Plano-convex lenses of about 20 cms.

Feb., 1916] Spectra of Some Halogeji Compounds 119

focal length were waxed on to the ends to assist in focusing the
light, passing as a parallel beam of light through the tube, upon
the slit of the spectrometer. The source of illumination was a
Nernst glower. The tube was heated by a long gas burner
set between the water cooled jackets. Two chief difficulties
arose in the use of the apparatus; one was the condensation
of the vapor on the cold glass ends, the other was leakage at
high temperatures. Various schemes for improvement were
tried, but the time alloted to this portion of the work was too
meager to obtain satisfactory results except possibly in one case.

Several trials were made with stannic chloride, a substance
which vaporizes readily at a low temperature. Heat was applied
rapidly and subsequently a volume of vapor was produced
which appeared to cut off all the light coming through the
spectroscope, except a broad band in the red end. By making
comparison with the emission spectrum for this compound, it
seems probable that the absorption and emission spectra
are complementary.

The emission spectra, being produced under electrical
excitation, are due to ionization set up by some external agency.
Since there is no such external, source of ionization in the
experiments just described, it might be concluded that there
would be no ions present and hence, if certain lines of reasoning
relative to the production of absorption spectra were followed
out, no absorption spectra could be expected. An examination
of the inside of the tube, after using mercuric iodide or stannic
chloride for example, showed a bright metallic mirror at the
water-cooled ends. This proved that dissociation must have
occurred and therefore presumably some ionization; a consid-
erable number of experiments by various investigators (Rich-
ardson, Willows, Beattie, Schmidt, Sheard et al.) have shown
the existence of negative ions of iodine and bromine when their
salts have been heated under potential.*

*It is of interest in this connection to cite the experiments of Lenard (Annalen
der Physik, 17, page 197, 190.5) made with beads of the fused salts of the alkali
metals supported upon platinum wires in the Bunsen flame. The emitted light
was found to be strongly colored, the color depending upon the metal. An exam-
ination of the absorption spectra of the fused salts showed that the color of the
transmitted light was complementary to that of the emitted light, as should
follow from KirchhofT's law. The salts were colorless, however, when cold
showing that some sort of dissociation resulted from the high temperatures,
metallic ions being set free which had the property of absorbing and emitting
radiations of the same frequency. In the case of most of the salts examined the
color was found to depend upon the metal, i. e., upon the cations; the borates and
silicates were marked exceptions, however, the color being due to the anions, the
nature of the metal being immaterial.

120 The Ohio Journal of Science [Vol. XVI, No. 4,

DEPOSITION OF METALLIC MIRRORS.

When a discharge tube was opened after a spectral examina-
tion of a salt it was found that there was a thin metallic deposit
covering the inside of the lower electrode in the portion near
the water cooled end. It cannot be stated that these were
present in the case of every substance investigated; but in the
case of mercuric iodide, cadmium iodide, zinc bromide and tin
chloride metallic mirrors, almost as brilliant as if polished, were
noticed. This shows that considerable dissociation and reduc-
tion of the compound occurred under heat and the electrical
excitation.

These mirrors, as stated in a preceding paragraph, were
also obtained with two compounds which were heated in the
apparatus used for investigating absorption spectra. The
mirrors obtained from stannic chloride were almost as bright
as is the surface of clean mercury. In these experiments no
external agent was used except the heat. It is therefore appar-
ent that under heat alone some metallic compounds (at least
halogens) are dissociated, the metal being set free. There can
have been no reducing agent present, such as would have been
the case had the salts been introduced into the flame, unless the
residual gas present in the tube could have acted as such agent.
This seems improbable in view of the low pressures used.

vSome interesting results on "Flame Reactions" have been
published recently by Bancroft and Weiser (Journal of Physical
Chemistry, Vol. XVIII, 1914) in which they have obtained
metallic deposits on cold porcelain introduced into a Bunsen
flame which was fed with chlorides and nitrates of copper,
cadmium, tin, mercury and silver. These experimenters con-
cluded that "the reducing action of the flame gases is not
essential, though at times it may increase the decomposition."
With this conclusion the writers of this paper are in accord
and feel that the results detailed above establish the legitimacy
of this conclusion since the question of flame gases does not enter.

POSSIBLE NATURE OF THE SYSTEMS PRODUCING THE BAND

SPECTRA OF THE COMPOUNDS.

In order to present the experimental facts in concise form
and to provide a ready reference table in connection with the
ensuing discussion the following brief resume of the data
obtained on the emission spectra of the compounds is introduced

MERCURIC

ZINC

6072-5845

5605-5535

5610-5535

5195-5132

5195-5116

4828-4788

4829-4780

4506-4470

4450-4375

Bromides

Calcium

5500-4850

Mercurous

5075-4912

Zinc

5550-5150

Feb., 1916] Spectra of Some Halogen Compounds 121

Continuous Spectral Regions or Bands.

Iodides.

CALCIUM

6075-5845 (?)

5615-5528

5180-5100

4830-4787

4507-4465

4438-4360 (?)

Chlorides

Stannic 5800-4400

Ferric 5900-4800

Manganous 5900-4450

A survey of these results shows that the banded or con-
tinuous regions are in general nearly identical amongst the
members of any particular group of halogens. In the case of the
chlorides and bromides the continuous regions were diffuse or
shaded off at each end. In the case of the iodides, however,
all the bands except those at 4500-4470 and 4450-4370 were
fairly sharp at the longer wave length ends.

It appears that there is some common vibrating or emitting
system which is operative in each of these halogen classes.
The only common element present, so far as known, in the
iodides examined is iodine, and so on for the chlorides and
bromides. It seems reasonable to attribute the general similar-
ity of spectra in each of the halogen groups to the halogen
members acting directly or in combination as hereinafter
suggested. The compounds on initial heating showed, in
general, some lines characteristic of the base and of the radical.
There is, therefore, some dissociation of the original compounds
and production of ions, both positive and negative, some of
which to say the least are elemental constituents of the com-
pound designated.

The residues from the various salts were difTerent in color
and structure from the compound introduced. For example,
the residue from stannic chloride (original salt white in color)
came out violet, manganous chloride (original salt slightly
pinkish) came out lavender in color. These color effects
indicate chemical changes. Examinations of several residues,
using the polarizing microscope, were very kindly made by
Mr. J. B. Dickson, then of the Department of Chemistry of

122 The Ohio Journal of Science [Vol. XVI, No. 4,

the Ohio State University. The following notes are taken
from his report:

Hg Br. Metallic mercury unmistakably present. Tiny globules of mercury
found under 'scope on surface of lumps of Hg Br.

Cd I-i. Showed presence of metallic cadmium by reflected light.

Zn Br-i. Could get no evidence of presence of free zinc.

Fe-i Cl(,. Under magnifier, presence of numerous green spots showing existence
of FeClo, or Fe2Cl4, (the latter formula being now considered
preferable by chemists).

Ca Br-y. All tests showed presence of metallic calcium.

Hg I>. In this case there was considerable reduction to Hg I.

The writers are disposed therefore to believe that there is
dissociation and ionization of some portions of the original
compound into its basic and radical components, but that there
is also, under the proper conditions, a dissociation of the
vaporized salt into a positively charged sub-compound and
negatively charged radical. To illustrate, let us take mercuric
iodide (Hg I2). This in part dissociates into Hg+-|- or 2 Hg+ and
1= or 2 I_, or positive ions of mercury carrying a single or
double charge and negative ions of iodide carrying a single or
double charge. In addition there is, as evidenced by the
analysis of the residue after heating, a considerable dissociation
into Hg 1+ or positively charged mercurous iodide and I_ or
negatively charged ions of iodine. It is probable that the
banded or continuous spectra arise from the recombination
of the oppositely charged mercurous iodide and iodine which
are formed from the vaporized, non-dissociated salt present
in the capillary portion of the discharge tube, although it is
not likely that there is a permanent recombination of mercuric
chloride formed. We can say that we have the emission
spectrum of the original compound if we admit such a process.
That some such process is operative is made plausible by the
fact that the banded regions in the case of the iodides have their
heads at or near a prominent iodine line. In the case of the
chlorides we find extended continuous regions which include
the spectrum from the blue to the orange-yellow region.
There is no evidence of lines or bands in the red end of the
spectrum. The .spectrum of chlorine exhibits a richness of
lines in the region 5()()()-410() Angstroms and a dearth of
anything in the red region except the line 6095. The same
explanation made for the iodides seems satisfactory here. If
stannic chloride dissociates in part into ions of tin and chlorine
and in part into positively charged molecules of stannous

Feb., 1916] Spectra of Some Halogen Compounds 123

chloride and negatively charged ions of chlorine we should
expect the experimental results detailed above. Furthermore,
none of these banded regions appeared to be associated in any
manner with the element making up the base of the salt. This
is clearly proven, we believe, by the fact that the banded
regions were practically identical in any halogen group irrespec-
tive of the base present. Possibly the best illustration is
afforded by mercuric iodide in which the lines characteristic
of mercury coexisted with the broad bands and were prominent
and sharp with no tendency towards broadening or diffuseness.
These experiments also throw light upon the investigations
of Professor O. W. Richardson on the specific charge of the ions.
In investigating zinc iodide he found that the negative ions were
iodine and the positive ions, during the initial stages of heating,
correspond most closely to ions of zinc carr3dng a double charge.
We found the spectrum of zinc and iodine present in the early
stages of heating, but also found that the zinc lines soon dis-
appeared. In the case of manganous chloride, Richardson
found initial values which would correspond to manganese,
but with further heating a value of "m" equal to 90 indicating
possibly the existence of positively charged Mn CI. The
results of the experiments made by the writers support such
conclusions as these. In the case of ferric chloride no spectral
evidence of the presence of iron was found at any period of the
experimentation, but after sufficient heating a continuous
spectrum within the limits of 5900 and 4800 Angstroms was
developed. This may indicate, if we follow out the line of
argument given in the preceding paragraph, a dissociation into
negative ions of chlorine, (CL) or (2C1_) and positively
charged sub-compounds of iron and chlorine (Fe C1++). If such
a positively charged molecular structure existed it would have a
value of "m" equal to 45, which would be in accord with
Richardson's experimental values of 40.2, 39.3 and 39.8. It is
to be stated in this connection, however, that the analysis of
the residue from Fe CI3 did not show the existence of such a
compound as Fe CI, but did show the sub-compound Fe CI2.
The chemistry of compounds at high temperatures is still
somewhat of an unopened book ; without doubt there are formed
and exist at such temperatures molecular structures or sub-
compounds or recombinations of the elements of the original
substance of which we know little. The postulation of the

124 The Ohio Journal of Science [Vol. XVI, No. 4,

formation of such ionized structures seems to us to be as likely
a basis of explanation of some of the values of the specific
charge of the ions obtained as the present partially accepted
theories of gas ions or ions characteristic of the elements present
when salts are heated under potential. The latter premise is
apparently correct in many instances, but the assumption of an
impurity, such as sodium, when the value of "m" lies near
23, or of potassium when the value of "m" lies near 39, seems
R trifle far fetched in some instances.

CONCLUSIONS.

1. The halogen compounds investigated exhibit broad
bands or continuous spectra which are probably due to the
formation of positively charged sub-compounds and subsequent
recombination with the negatively charged ions characteristic
of the radical of the salt.

2. The bands and continuous spectra obtained are in
general agreement as to number, position and character for
the compounds of any specified haloid investigated. Continu-
ous spectra are exhibited by the chlorides and bromides and
several bands by the iodides.

3. The radical and not the basic element of the compound
investigated appears to be the essential controlling factor.

4. There is present in the initial stages of heating of
several of the compounds a dissociation into positive and
negative ions spectrally determined to be the two components
of the original compound.

5. There is found in the discharge tube in nearly every case
a metallic deposit or mirror of the base of the salt investigated.
These deposits were also found when no external ionizing
agent other than heat was employed. These experiments
settle in the negative the question as to whether or not the
reducing action of the flame gases of a Bunsen burner is neces-
sary for the deposition of the metallic constituent of a salt.

6. The evidence points to the conclusion that there is an
absorption spectrum of the vapor of the compound which
corresponds to its emission spectrum.

Ohio State University.

SUNFISH NESTS OF BEIMILLER'S COVE.*

F. H. Krecker.

During the night of July 4-5, 1915, a strong southwest
wind drove the water of Sandusky Bay out into Lake Erie in
such quantities that it receded thirty feet from the shore Hne
in what is known as Beimiller's Cove. This decided drop in
the water level brought to my attention some nests of the
sunfish, Eupomotis gibbosus, which circumstance suggested a
study of the conditions under which the fish of this region
breed. As is well known many of the fishes of the Great Lakes
choose the shallow bays and coves for breeding places. An
investigation of these localities is of some importance, since
with the present rapid occupation of these shores by man and
their consequent alteration, the neighboring waters lose much
of their value for breeding purposes. The finding of suitable
nesting places must be presenting a greater problem to the
fish each year.

The observations recorded in this article have to do with
conditions in Beimiller's Cove alone and are therefore not
sufficiently extensive to draw conclusions regarding the general
situation. And even what has been recorded from this cove
is to be looked upon chiefly as a preliminary study. There are
some points of interest, however, worth noting. It is hoped
that further and more far reaching observations to be under-
taken in the future may throw considerable light upon these
questions.

Beimiller's Cove is an indentation in the sandy peninsula
known as Cedar Point, which stretches across the eastern end
of Sandusky Bay from the southeast and separates it from Lake
Erie. The cove lies on a line running southeast and northwest
and is about half a mile long and one-third of a mile wide.
At its inner end there empties a sewage canal. The depth
of water varies from less than a foot at the inner end and along
the sides to six or eight feet in the center and at the mouth of
the cove. The bottom is covered with a luxuriant growth of
aquatic plants, such as Myriophyllum. Along the shores are
reeds, particularly Scirpus americanus. The bottom and shores

*Contribution from the Dept. of Zoology and Entomology, Ohio State Uni-
versity, No. 45.

1^5

126

The Ohio Journal of Science [Vol. XVI, No. 4,

toward the inner end are mucky. Water lillies are abundant
here. The western shore is thickly covered with reeds, at
places there are marsh conditions and nearly everywhere there
is a deposit of dead vegetation. Where this vegetation is
absent a sandy or pebbly bottom is exposed. The bottom
along three-fourths of the eastern shore for a distance of fifteen

Figure 1. Large nest completely exposed. Some water still covers bottom
of nest. Darker spot in center of this marks area within which eggs lie.

to twenty-feet out from the shore line is sandy and pebbly and
is sparsely covered with vegetation. The difference between
the eastern and the western shore is due partly to the influence
of winds and currents which tend to pile up debris on the
western side.

The observations on the nests were made at intervals of
about a week between July 5 and July 27, 1915. Within this
period the total number of nests coimted was 410. These

Feb., 19 IG] Siinfish Nests of Beimillers Cove

127

were divided into two distinct types, large nests and small
nests. 1 shall describe the larger type first.

The large nests were found on the sandy stretches of bottom.
A good conception of their appearance can be gained from
the photographs shown in Figures 1 and 2. They are crater
like depressions in the sand at the bottom of which were coarse
sand or pebbles and sometimes a large solid object, such as a

Figure 2. Three large nests exposed on characteristic bottom,
in center adjoins that of a nest to the left.

Rim of nest

half of a clam shell or a piece of wood that had happened to be
buried at the point selected. The depressions were sometimes
circular but more often oval. The length of the largest nests
measured was thirty-six inches across the top and their width
twenty-seven inches. Some of the nests were twenty-five
inches by thirty inches and a few were as small as eighteen
by twenty inches. The depth of the nests averaged three
inches. This, however, depended upon the amount of sand

128 The Ohio Journal of Science [Vol. XVI, No. 4,

that had to be scooped out to obtain the proper bottom. The
eggs He in the apex of the depression. They are approximately
one millimeter in diameter and they blend so well in color with
the sand as to make them rather hard to detect. The large
nests were confined to a fairly well defined zone which began
about ten feet from the water's edge and extended outward to
a line between eighteen and twenty feet from shore. Most of
them were in water which was from eleven to fourteen inches
deep. A few were in fifteen inches of water.

In describing the location of the nests reference will be made
to the outline sketch of the cove shown in Figure 4. The larger
rings represent the large nests and the smaller rings indicate
the small nests. The letters are for convenience in description
and are explained in the text.

On July 5, a group of large nests was found on the eastern
side opposite the point A on a sandy bottom with some vegeta-
tion. This group lay approximately fifteen feet from shore on
the border line of the mucky region at the inner end of the cove.
Some of these nests are shown in Figure 3. Between A and the
Lake Laboratory landing (L) fifteen other nests were scattered.
These were likewise on a sandy bottom and for the most part
lay singly. Three of these are to be seen in Figure 2. There
were also some large nests near the south side of the landing,
but they were not counted at this time.

From July 12 to 16, a survey was made of the whole eastern
shore. On this side all the nests were in the strip of sandy and
pebbly bottom, previously mentioned, which was only sparsely
covered with vegetation and extended for twenty-five to thirty
feet from shore. The conditions were in general like those
shown in Figure 2. Between the above dates 138 nests were
counted from the landing to the point H, a distance of about
a hundred and fifty yards. No nests were found beyond H.

By July 27 there were no occupied nests north of the Lake
Laboratory landing and most of the nests previously seen
south of this were no longer in use. However, there were some
fresh nests among the old ones near H and others were now
found as far down as S, at which point there are the remains
of an old scow. The total number of nests for the region L to
S was thirty. Of these eleven were between H and S. From
S to M there was a firm, sandy bottom, but there were no nests

Feb., 1916] Sunfish Nests of Beimillers Cove

129

here. In the region M there was a mucky bottom. From M to
P the bottom was again favorable. About K there were three
scattered nests. In the region of N there were sixteen nests.
These nests were in eighteen inches of water.

On the western side there was no continuous stretch of
open sandy bottom such as was found on the opposite side.
The belt of reeds extended out quite a distance, in some spots
ten to fifteen and twenty feet, and at these points other aquatic

Figure 3. Group of the nests at A (Fig. 4), bottom becoming mucky,

plants grew from the cove side up to the reed line, thus isolating
patches of open bottom.

The surve}^ of the western shore was made between July
12 and 19. In the indentation at D there was a good growth of
water lillies, the shores were marshy, the bottom muddy and
the water frequently so tainted with sewage as to be greasy.
There were no nests here. Along the short stretch a, there was
a firm, sandy and open bottom. Here seven nests were found.
The inlet B had no nests; its character was similar to that of D.
The points a, b, c, d, e, f, g, h, i, j, k had a sandy and com-
paratively open bottom.

130

The Ohio Journal of Science [Vol. XVI, No. 4,

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Feb., 1916] Sunfish Nests of Beimille/ s Cove 131

The following table gives the number of nests at each point :

LARGE NESTS SMALL XESTS
a 7

b 18 2

c 10

d 17 1

e 14

f 14 5

g 4

h 12

i 3

j 3

k 1

Total 103 8

The nests at g were among reeds. At v the bottom was
clear and sandy and appeared to be ideal for nests but none was
found. The total number of large nests, including those on
both shores, was 290.

The other type of nests, the small nests, were approximately
circular and had an averaged diameter of seven inches. Prac-
tically all of them were on the eastern side. With two excep-
tions they were found at a distance not greater than six feet
from the shore, most of them within three or four feet of it.
The exceptions were two widely separated nests which were
fifteen feet from the shore line. In the zone of more usual
occurrence there was a pebbly bottom and a fringe of reeds,
largely Scirpus americanus. The nests were made on the
pebbles among the reeds. A photograph of this type is shown
in Figure 5 between the arrows.

The depressions in many cases were so shallow that their
outlines could frequently only be determined by the fact that
the pebbles had been fanned clean. The roots of reeds were
often at one side of a nest but since the reeds grew close together
this could not well be avoided. They were never found in
more than seven inches of water, barring the exceptions noted,
and some were in barely enough water to cover them.

During the period July 12 to 16, 105 of these small nests
were found on the eastern shore between the points L and H.
By July 27 they were found as far down as the point T. On
this date sixteen of them were counted between H and T.
Although I made careful search, I could discover them no
where else on the eastern side. In the survey of the western
shore made from July 12 to 19, only eight small nests were
found. Two of them were located at the point /;, one at d and

132

The Ohio Journal of Science [Vol. XVI, No. 4,

five at /. The total number of small nests, including those
on both shores, was 129.

H In a general consideration of the sunfish nests in the cove
several features should be noted. The type of bottom which
appears to be most suitable for nest building is one composed of
sand, or sand and pebbles, with little or no vegetation. This is
borne out by the fact that on the sandy and open bottom of the

Figure 5. Small nest, between the arrows, in a typical location.
Photograph taken through the water.

eastern shore there was a total of 308 nests whereas along the
more overgrown western shore there were only 111 nests.
Also on comparing the eastern with the western shore, it will
be seen that in each case the nests were almost exclusively
where the bottom was of the character described. On the
western side suitable areas were found from a to k and on the
eastern side there was an almost unbroken stretch from A to P.
However, the character of the bottom does not appear to
be the only determining factor in nest location. The stretch

Feb., 1916] Siinfish Nests of Beimiller's Cove 133

of shore at v is apparently as favorable as that along the most of
the eastern side, considerably more so than much on the western
side, which was occupied, and yet in this stretch there were
no nests. There is also a similar strip on the eastern side
between S and M, which was unoccupied. In fact, taken as a
whole, the eastern side presents more favorable surroundings
than does the western side and all the nests on the latter shore
could have been accommodated on the opposite one. These
circumstances suggest that other factors in addition to the
character of the bottom aid in determining the matter of
location.

What these other influences are is not yet clear. An
element of chance with regard to the shore the fishes follow as
they enter the cove may enter into the choice. If anything
approximating suitable conditions are found on the shore
followed they probably nest without seeking farther.

Another factor which apparently has some bearing is the
proximity of other nests. This is to be gathered from the fact
that there is very clearly a tendency to build the nests in
groups independently of any influence which restricted area
may have in this direction. The grouping of nests on the
western shore can be credited in part to restricted surroundings.
However, on the eastern side where there was plenty of space
to permit a wide distribution, there was at certain points "a
decided grouping. This applies to both types although it
was more generally true of the small type. Three or four
large nests were frequently found rather close together and in
some cases they were so near each other that their rims touched.
Two such nests are to be seen in Figure 2. One of the most exten-
sive groups of large nests was foimd north of the laboratory land-
ing at A. A part of this group is shown in Figure 3. The small
nests nearly always occurred in groups. I have a record of only
ten solitary small nests. They were frequently placed in triangu-
lar groups of three, the members of a group lying as close together
as they well could. In other instances there were as many as
five or six nests within a short distance of each other. There
would then be an interval without nests, although apparently
suitable for the purpose, followed by another group.

One other matter of interest with regard to location is the
fact, already pointed out, that each type of nest was confined
to a distinct zone. This condition was well shown on the

134 The Ohio Journal of Science [Vol. XVI, No. 4,

eastern side, where there was a distance of four feet between the
two zones. The zone of large nests began ten feet from shore,
whereas the small nest zone ended six feet from the water's
edge. I have no data at hand that afford an entirely satis-
factory explanation of this separation. The position of the
small nests along the edge of the water is hardly favorable
for the hatching of eggs since the constant fluctuation in water
level frequently causes some of the nests to be uncovered.
Occasionally they are exposed long enough to destroy the eggs.
The fish guarding the small nests were not as large as those
on the larger nests and it is possible that they were unequal
to the task of forming nests in the deeper sand farther from
shore. It is possible also that they sought the shallow water
to escape enemies. However, I saw nothing to indicate that
they were forced to this location by the larger individuals.

A condition of considerable importance from the stand-
point of the cove as a breeding place is that it is being con-
taminated with sewage. Since an open sandy bottom is
apparently such an important factor in nesting conditions
its obliteration is certain to have harmful results. To a certain
extent the sewage is having this effect. It is being deposited
over the inner end of the cove and especially over that part
about the mouth of the sewage canal. However the direct
effects of the sewage deposit are probably not as great as are
its indirect effects. The latter are brought to bear through
the fertilizing action of the sewage upon the plants that take
possession of the bottom. The growth of the plants in the
cove is luxuriant even for a region in which aquatic plants are
abundant. The sewage also has a harmful influence through
its vitiating effect upon the water. The situation is such that
this effect is confined mainly to the western side, and probably
as yet, it is no great factor even here, since patches of sand
within the contaminated are occupied, as for example at a.
Nevertheless the results are disastrous where the sewage
concentration is great, as it is near the mouth of the canal.
Its influence here may be estimated from the fact that some
carp kept in a "live box" near the mouth of the canal died;
and carp are not usually credited with seeking the purest water.
If the sewage continues to be emptied into the cove, as it
doubtless will be, a marked influence upon the fish visiting the
locality will probably be noticeable within a few years.

Ohio State University, Columlnis.

HEXAGON NOTATION.

R. D. BOHANNAN.

(1) Salmon, in the "Notes" at the end of his Conic Sections
designates by <| , \ the point of intersection of the Hnes ab,

de; bv

the Pascal line which contains the three

(h)

ab, cd, ef
de, fa, bc^

points indicated by the vertical columns; and by the following
a g-point and an h-point, respectively:

ab, de, cf,l fab, ce, df'

^ cd, fa, be, ^ (g) ; < cd, bf , ae >

[ef, be, ad, J [ef, ac, bd^

The lines in (g) (h), taken in pairs, indicate the Pascal
lines which meet in a point, but the ItJies do ?wt give the hexagons.
In (h) only two Pascals are indicated, since ce, ac, do not meet
on the Pascal line, nor do df and bd.

To get the hexagon indicated by the first and second lines
of (g) start with ab of the first line; look up the letter with b
in the second line, giving abe: then the letter with e in the
first line, abed; then that with d in the second line, abedc; then
that with f in the first line, getting, finally, abedcf.

Treating the pairs of lines in (g), (h) in this way we get,
rather tediously, the hexagons:

fabedcfl fabfdce^

■j cdafeb M g) ; i cdbfea

[efcbadj [efdbac^

(2) I give here a notation which indicates the hexagons
by horizontal lines, as also their Pascal lines, when horizontal
lines are taken in pairs. The points (g), (h) above are:

ab, ed, cf' (1)

(h)

\ cd, af , eb (2) (gO ;
[ef, cb, adj (3)

ab, fd, eel (1)

dc, ae, fb I (2) (h')

ef, db, ac[ (3)

[ba, ec, dfj (1').

In (g') line (2) is formed from line (1) by writing under each
segment of (1) its opposite segment in (1), reversing the hexagon
order of letters in {1): (3) from (2) as (2) from (1); (1) and (2)
give the Pascal line of (1); (2) and (3) that of (2); (3), (1) that
of (3).

135

136 The Ohio Journal of Science [Vol. XVI, No. 4,

In (g') there is also cyclic permutation of the initial letters
of the segments in one direction (to the right) and of the final
letters in the other direction (to the left). This offers the
easiest way of writing (g')-

In (h'), line (2) is formed from line (1) by setting under
each segment of (1) its opposite segment, retaining the hexagon
order of letters in {!) in one column (here the first) and reversing
it in- the other two; (3) from (2) as (2) from (1); (1') from (3)
as (3) from (2); (1') is (1). The lines (1) and (2) give the
Pascal of (1); (2), (3) that of (2); (3), (1') that of (3).

(3) When only the hexagons which enter into (g) and
(h) are desired, they may be written thus :

'a b c d e f ) (1) fc e a, b f d] (1)

af cbed (2) (g"); ]eac, dbf^ (2) (h")

^a d c f e bj (3) [a c e, f d bj (3)

In (g") one set of alternate letters (here a, c, e) is held
fixed; the other set permuted cyclically (in either direction).

In (h"), line (1) is divided into two groups by a comma.
Each group is permuted cyclically, the one in the opposite
direction of the other. If the hexagons in (h") are to indicate
the same point as (h'), set astride the comma the segment of
the first line of (h) in the column which was to hold the hexagon
order (here ab) in (h")-

These notations lend themselves, as will be seen in the
following, most readily to determine the whole geometry of the
hexagon configuration.

(4) The g-point of any hexagon is the center of perspective
of its two triangles of alternate sides, the axis of perspective
being the Pascal line of the hexagon.

To write the g-point of any hexagon, interchange any pair
of its alternate letters for the first line and proceed as in (g') or

For a b c d e f (interchanging c and e) it is:

fab, ed, cfl fa b e d c f'

\ cd, af, eb > (gO or <^afebcd^ (g2).

[ef, cb, adj [a d e f c b^

(5) The conjugate g-point of any given g-point

The g-point of any hexagon of a g-point is one and the same
g-point (the conjugate g-point).

Feb., 1916]

Hexagon Notation

137

For (gi) of (4) it is g'j or g'o following:

ab, cd, efl fa b c d e f]

ed, af, cb \ (g'l) ; <^ a f c b e d ^ (g's).

cf, eb, adj [a d c f e b ,

Of a pair of conjugate g-points, one is inside the conic; the
other outside; the line joining them is divided harmonically
by the conic (Steiner).

The g-point on the Pascal of any hexagon is conjugate to
that of the hexagon.

(6) To find three hexagons for which a given g-point is the
g-point.

Write the conjugate g-point.

(7) The two ordinary h-points of any hexagon and how to
write them. For any hexagon, as a b c d e f (1), write the
triangle of alternate letters:

8.C, CC, C3-.

Write under each letter its opposite letter in (1) giving,

I ac, ce, ea ' /q-vN
\df, fb, bdj ^ -'■

The triangle, T, whose vertices are indicated by vertical
columns here, is in perspective with each of the triangles of
alternate sides of (1), giving for (1) two h-points. (T) may be
called the Pascal triangle of the given hexagon.

To write the h-points of (/), wTite (1) forward and backwards
as in,

a b c d e f (1)
a f e d c b (2)

Group the alternate letters of (1), (2) in two groups, in
opposite directions, giving for (1) and (2) respectively:

ace, fdb;aec, bdf,

as the first lines of the desired h-points. Then complete as in
section (3) giving:

ace, fdb] faec, bdf"]

icea,, bf d [> (hi); ^ eca, fbd |^ (ho).

eac, dbfj [cae, dfb^

We call these the two ordinary h-points of the corresponding
hexagon (1), to distinguish them from the unique h- point of the
same hexagon (see section (9) ).

138 The Ohio Joiirjial of Science [Vol. XVI, No. 4,

(8) The two ordifiary hexagons of any h-point.

While the hexagons of a g-point give only one g-point, they
give, not six h-points, but only three.

Any two hexagons related as

ab, cd, ef
ba, dc, fe

will have one of their ordinary h-points in common. This
relation is the same as,

ab, cd, ef

ab, ef, cd

The hexagons of any g-point show this sort of relation in
pairs.

For a given h-point, like

ace, fdb]
cea, bfd \ (C)
eac, dbfj

its two ordinary hexagons are given by reading the first and
last letters of each line, in regular order, down the lines (or
last and first) giving,

ab, cd, ef

ba, dc, fe;

also straddling the comma.

In the notation like h' of Section (2), the two hexagons
are gotten by reading zig-zag, the column which retained the
hexagon order. For h', it was the first column, giving ab,
cd, ef and ba, de, fe.

(9) The unique h-poi?ii of any hexagon.

In any h-point, as (C) in (8), there are only nine of the
fifteen hexagon lines. In (C) they are ac, ce, ef, fd, db, ba,
ea, bf, cd.

The remaining six lines form a hexagon related thus uniquely
to the given h-point.

To write the first line of the unique h-point of any hexagon,
a b c d e f (1), write the alternate letters in two groups; ace, bfd;
the second group begins with the letter adjacent the initial
letter of the first group on the side in the direction of the first
grouping and is taken in the direction opposite the first.

Feb., 1916] Hexagon Notation 139

This gives for a b c d e f , the unique h-point.

ace, bfdl
< cea, dbf ^ (D)
[eac, fdb^

The geometric relation of a hexagon and its unique h-point
will appear later. (See section 40).

(10) To write the unique hexagon of any given h-point.

Set the fourth letter of any line between the first and second ;
the sixth between the second and third.

That for (C) is a f c b e d;
That for (D) is a b c d e f.

(11) Relation between the unique hexagon of an h-point and
its two ordinary hexagons.

The two ordinary hexagons of (D) in (9) are, by (8),

ad, cf, eb
da, fc, be

and the unique hexagon is, in (10), a b c d e f, but these three
hexagons are those of the g-point.

a b c d e f]

<jafcbed!^
[a d c f e b]

(12) To write a g-point and two h-points on a straight line.
It follows at once from the definition of these points that the

g-point and the two ordinary h-points of any hexagon are on a
straight line.

(13) To write a g-point and three h-points on a line. (Salmon's
G-line).

The hexagons of any g-point will give g', hi, ho on a line;
also g', h2, ha on a line; also g', ha, hi (See sec. (8), (11), (12) ).

Therefore, g', hi, h2, hs are on a line, where g' is the conjugate
g-point of the given g-point. (See (5) ).

Therefore, the g-point and three unique h-points of the hexagon
of a g-point are collinear. And what is the same thing and the
same line, the g-point and three pairs of ordinary h-points of the
hexagon of a g-point are a g-point and three h-points on a line.

(14) The number of g-points.

In forming g' in section (2) we reversed the hexagon order
of segments in each column. This can be done in only one way.

140 The Ohio Journal of Science [Vol. XVI, No. 4,.

Therefore each hexagon enters into only one g-point. Therefore
twenty g-points.

(15) The number of h-points, and how to write three h-points
on any Pascal line.

In forming (h') of section (2) we held the hexagon order in
one column and reversed in two. This can be done in three
ways, therefore each hexagon enters into three h-points, there-
fore, three times as many h-points as g-points. Therefore
sixty h-points.

This is also shown in the notation of section (3), since
the line (1) can be grouped in three ways as indicated.

To write three h-points on a Pascal line, proceed as in h' of
(2), retaining the hexagon order in columns 1, 2, 3, in order;,
or, if using the notation in (3), use as initial lines, abc, def ; bed,
efa; cde, fab.

(16) The number of G-lines.

By (13) each g-point gives a G-line through its conjugate
g-point.

Therefore, twenty G-lines.

(17) Given a g-poirit to write the three h-points on a G-line
with it.

Write the conjugate g-point (5) and the three h-points
unique to its hexagons ( (9), (13) ). Also on any Pascal line
there is one g-point and three h-points, ( (14, (15) ).

(18) Given one h-point of a G-line to write the g-point and two
remaining h-points.

Write the hexagon unique (10) to the given h-point; then the
two hexagons which enter with this hexagon into a g-point
( (2) or (3) ) ; then their two unique h-points, and the conjugate
g-point. Thus, through any h-point goes only one g-line.

(19) To write three g-points on a line.

Write the g-points of the hexagons of any h-point. The
triangles of alternate sides of the hexagons of an h-point are
but three in perspective in pairs at three g-points (4), with axes
of perspective concurrent in the h-point; therefore the three
centers of perspective are collinear.

(20) To write three lines of three g-points each, with a grpoint
in common.

Write the three lines of g-points of three h-points on any
Pascal line, (15). The g-point in common to the three lines is
the g-point conjugate to that on the common Pascal line.
( (19) and (5) ).

Feb., 1916] Hexagon Notation 141

(21) The nine h-points on three Pascal lines which meet in
a g-point establish the same three lines noted in {20). (See (11) ).

If the g-point lines in (20) are,

fe ' §^> S3
& ' &'4» &5
S > &6> &7

those noted in (21) will be (in addition), easily tested by writing
them in full:

g', g2, gs;

cr' cr, cr^-

g', g6, gio;

g', g3, gs;

g', g5, gg;

g', g7, gio;

which are the same lines as in (20), since two points fix a line.
Here g' is the conjugate of the g-point of the three given Pascal
lines.

(22) By (21) the nine h-points on three Pascal lines meeting
at a g-point establish three lines of four g-points each through
the conjugate g-poi?it. (Salmon's I-lines).

These lines are established by difi'erent sets of three points,
the conjugate g-point always included.

(23) Through the g-point where three Pascal lines meet goes
also one G-line {17), with three h-points. These three h-points
establish the same I-lines noted in {22), by sets of three points, the
conjugate g-point always excluded.

The lines will be (if written out) :

g2, g3, gs;
g4, go, gg;
gs, g7, gio.

(24) By (22 and (23) it follows that the twelve h-points
of the four lines of h-points (three Pascal lines and one G-line)
passing through a g-point establish three I-lines of four g-points
each through the conjugate g-point,

(25) By (24) there are fifteen I-Hnes.

(26) By (24) there must be four h-points grouped about
a g-point (one on each of its Pascal lines and one on its G-line)
which establish a single line of four g-points through the con-
jugate g-point; and for each g-point three such h-point
quadrangles.

142

The Ohio Journal of Science [Vol. XVI, No. 4,

(27) To write such a quadrangle of h-points as noted in (26)^

a b c, d e f (1)
a c e, b d f (2)
a e d, c b f (3)
a d b, e c f (4)

(1), (2), (3), (4) form the initial lines, properly grouped
for such a quadrangle. Line (2) is formed from (1) by taking
alternate letters, in regular order, in two groups as indicated;
(3) from (2) as (2) from (1); (4) from (3) as (3) from (2). The
h-points with (1), (2), (3), (4) as initial lines are:

abc, def
\ bca, fde
[cab, efd

faed, cbf
eda, fcb ■■
[dae, bfc^

(hi) ;

ace, bdf"!
cea, fbd
eac, .dfb

(hoj.

fadb, ecf'
(hg); ^dba, f ec ^ (h4).

[bad, cfej

Now write by 4, the g-points of the hexagons in hi, ho, hs, h^,
and they will be respectively:

gi, g2, gs;
g3, g4, g2;

g2, gl, gi\
g4, g3, gl-

•*• gl' g2. gs and g4 are collinear.

(28) To write three such quadrangles of h-points (as in 27)
grouped about the g- point containing abcdef (1).

Group (1) in the three ways:

abc, def; bed, efa; cde, fab,
and form from each grouping a set as in (27).

(29) The three g-points conjugate to those on the Pascals of
an h- point are collinear.

They are conjugates by 5 and collinear by 19.

(30) The three g-points of the hexagons of an h-point are
collinear with the g-point on the Pascal of the hexagon, uniqne to
the h-point.

In 27, (h,) gave the g-points gi, ga, gs.
The second hexagon in h.2 gives:

c e b f a d

c f b d a e }- (g4) .

c d b e a f j

where the middle line is the hexagon unique to hi (10).

Feb., 1916] Hexagon Notation 143

(31) To write four g-points on an I-line.
Use (30), which shows there are 15 I-Hnes.

(32) The four g-points of an I-line are on the Pascals of the
hexagotis unique to the four h-points of the corresponding h-point
quadrangles as given in {27); as also on the Pascals of the hexagons
ordinary.

The hexagons unique to the four h-points in (27) are:

fadbf ce (1)1
J a b c f e d (2)

lacef db (3)f ^^^•

[ae df b c (4^
and (1) is in g4; (2) in gi; (3) in gs; (4) in g4.

[Note that hne (2) of (A) is formed from Hne (1), by writing
first the alternate letters of (1), abc; then the second set of
alternate letters of (1), beginning with the fourth letter from
the initial letter of the first set, the second set being taken in
the same direction as the first set. The set is unique].

By (11) the same g-points fixed by (A) are also on the
Pascals of the hexagons ordinary, one set of which for the
h-points of (27) is:

af, be, cd (I) ]

af, cd, eb (II)

af, eb, dc (III) [ ^^^•
af, dc, be (IV)

(33) Set (A) of (32) shows there are 15 I-lines, since any
line of (A) uniquely determines all the rest. There are thus
only 15 such complete quadrilaterals as (A).

In (A) there are 4 Pascal lines meeting in six Pascal points,
and the triangle of any three of the lines is the Pascal triangle
(7) of the fourth hexagon. These fifteen quadrilaterals deter-
mine the most important features of the hexagon geometry.
(See second paper.)

(34) To write three I-lines through any g-point.

Form from each line of the g-point a group like (A) of (32),
for the initial lines of the four g-points on each of the three
I-lines. Therefore through each g-point pass three I-lines of
four g-points each.

For the g-point

a b c d e f

a f c b e d}' (gi).

a d c f e b

144

The Ohio Journal of Science [Vol. XVI, No. 4,

The three hnes of g-points are (by initial lines)

'a b c d e f (gi)l fa f c b e d (gi)j fa d c f e b (gi)

a c e d f b (gs) I 1 a c e b d f (g5) I I a c e f b d (gg)

a e f d b c (ga) [ ' | a e d b f c (ge) ( ' ) a e b f d c (gg)

[a f b d c e (g4)J [a d f b c e (gr)] [a b d f c e (gio;

In a set of g-points like the ten above no two are conjugate
to each other.

(35) To write two sets of conjugate g-points, of ten points in
each set, each set having a point in it conjugate to a point in the
other set.

Treat two conjugate g-points as was (gi) of (34).

(36) To write four G-lines concurrejit in an i-point. (Sal-
mon's notation).

Write four g-points on a line (by (31) or (32) ) ; then the
three h-points unique to the hexagons of each of the collinear
g-points. This will give four lines containing three h-points
each, one line passing through each of the g-points conjugate
to the four collinear g-points.

These four g-lines are concurrent in an i-point.

The triangles of alternate sides of the hexagons of a g-point
are but three (A, B, C). Their Pascal triangles (7) are three
(Pi, P2, P3). By (4) A, B, C are in perspective at the conjugate
g-point (gi) ; by 7 and 8, A, Pi, Po are in perspective at hi;
B, P2, P3 at h2; C, P3, Pi at h.3. Therefore, g' , hi, ho, hs are
collinear (a G-line). It follows easily that for four collinear
g-points, the resulting four G-lines are concurrent,

(37) There are three i-points on each G-line.

Through each g-point there are three I-lines of four g-points
each (34). Each gives an i-point on the G-line through the
conjugate g-point, as in (3G).

(38) The three h-points unique to the hexagons of an h-point
are all on the Pascal line of the hexagon unique to the given h-point.

The h-point unique to a b c d e f (1) is, by (9),

face, bfd (2)^
cea, dbf (3n (hi).
^eac, fdb (4)^

Feb., 1916]

Hexagon Notation

145

The three h-points unique to (2), (3), (4) are:
'aef, cdbl (5) fcab, efd] (7) feed, abf] (9)

efa, bcd,^ (1) M ; <| abc, def ^ (1) (h.s) ; <| cde, f ab ^ (1) (h4)
^fae, dbcj (6) [bca, fdej (8) [dec, bfaj (10)

These all contain (1).

(39) The ten hexagons in {38) are a Veronese group.

In such a group there are ten h-points, on ten Pascal lines,
three h-points on each Pascal line, three Pascal lines through
each h-point; at each h-point two triangles in perspective, their
vertices h-points, their sides Pascal lines; the axis of perspective
being for each point the Pascal of the hexagon unique to the
center of the perspective. It is a group of ten Pascal lines and
their ten unique h-points.

(40) Geometric relation between an h-point and its unique
hexagon.

None of the hexagons, 2, 3, 4, in hi in 38 enter into the
h-points on the Pascal of abcdef (1), unique to (2, 3, 4). Thus
hi is the center of perspective and the Pascal of (1) the axis
of perspective for the two h-point triangles whose corresponding
sides are 5, 6; 7, 8; 9, 10.

In the accompanying figure, the unique h-points and Pascals
are numbered as II, 2; IV, 4; etc., giving ten centers of perspec-
tive, ten axes of perspective; for each center a pair of triangles
in perspective.

Tn:

Fig. 1. A Veronese group as in 38 and 40. Ten such groups.

146

The Ohio Journal of Science [Vol. XVI, No. 4,

(41) To write the six Veronese groups.

Select the six hexagons of two conjugate g-points and treat
each as was (1) in (38).

(42) A Veronese group may also be sorted out thus:
Start with any hexagon abcdef(l). Hold a, c fixed,

permute all the other letters cyclically (forward) ; then hold
c, e fixed; then e, a, giving:

fa b c d e f (1)
I a f c b d e (2)
' a e c f b d (3)

a d c e f b (4)
I c b e d f a (5)
i c a e b d f (6)
[c f e a b d (7)

e d a f b c (8)

e c a d f b (9)

e b a c d f (10)

(43) The six Veronese groups may be formed as in (42),
by starting with the six lines of two conjugate g-points.

(44) No two h-points of a Veronese group and no g-point
and h-point of such a group are connected by a G-line. These
lines tie the difi'erent groups, one h-point from each of three
groups, and a g-point from a fourth.

(45) The ten g-points in any Veronese group lie on five I -lines,
four points on each line, two lines through each h-point. {The
arrangement of the ordinary five point star, four point star, or
three point star).

Write a b c d e f forwards and backwards as in

ab, cd, ef (F)

af, ed, cb (B)

Form from (F) and (B) two groups as follows:

'ab, cd, ef (F) 1 faf, ed, cb (B)'

ab, ef, dc (2) , /* \ J af , cb, de (5)

ab, dc, fe (3) [ ^ '■ ' | af, de, be (6)

[ab, fe, cd (4) J [af, be, ed (7)

Here are seven hexagons in the Veronese group of (42).
On writing out the g-points on the Pascals of (Ai), they will
be gi, gs, g6, gv of 34; those on the Pascals of (Aa) are gi, gio gg, gs-

(A2)

Feb., 1916]

Hexagon Notatio7i

147

Thus any hexagon treated as in (Ai), (A2) will give two lines
of four g-points each, inside the same Veronese group. (The third
line of g-points runs to different groups).

Now reverse (2), (3), (4) and form similar groups to (Ai).

ad, ce, fb (4)
J ad, fb, ec (8)

ad, ec, bf (7)
^ad, bf, ce(10)J

(E).

ac, df, eb(2)l fae, fc, db (3)

ac, eb, fd(8) l.px I ae, db, cf (5),.-p^x ;

ac, fd, eb(9) T^ ' | ae, cf, bd(lO) T^ ' ]

ac, eb, df(6)j [ae, bd, fc (9)J

Here is a total of ten hexagons, all in the Veronese group
of (42).

Each set, Ai, A2, C, D, E indicates a line of four g-points;
and each hexagon occurs tw4ce. Therefore the g-points within
any Veronese group are on five lines, four points on each line
and two lines through each point.

('46) The star of g-points in each Veronese group.

Fig. 2. The g-point star in a Veronese Group. (As it might be).

As shown by Ai, Ao, C, D, E; 2 in Fig. 2 indicates the
g-point on the Pascal of hexagon (2).

A different arrangement of the points will give a three point
or four point star.

(47) Each pair of Veronese groups has an I -line of g-points
in commoji.

Any two hexagons related as (see 8),

ab, cd, ef (1)
ab, ef, cd (2)

148

The Ohio Journal of Science [Vol. XVI, No. 4,.

(2)

(F).

give, when used as the leading lines of a set like (Ai) in (45),
the same I-line; (2) will lead to the line gi, gv, ge, g5 on the
Pascals of (Ai) in (45).

ah, ef, cd'

ab, cd, fe

ab, fe, dc
[ab, dc, ef

But (Ai) and (F) belong to different Veronese groups.

Thus the six stars of the I-lines in the six Veronese groups
are linked by having one line in common between each pair;
each star has one line in common with each of the five other
stars. See (48), which shows that all the stars could not be
five pointed.

(48) Numerical table for the I-lines of g-points.

Selecting any g-point as

ab, cd, ef]
ed, af, cb j> (1)
cf, eb, adj

the collinear groups of I-lines through (1) have for initial lines
of their g-points:

ab, cd, ef (1)1 fed, af, cb (1)] fcf, eb, ad (1)

ab, ef, dc (2) I led, ch, fa (5) I I cf , ad, be (8) I

ab, dc, fe (3) | ' ] ed, fa, be (6) [ ' 1 cf, be, da (9) (

ab, fe, cd (4)J [ed, be, af (7)J [cf, da, eb (10)J

Denote by 2 the g-point on the Pascal of hexagon (2), etc.
and write the above lines thus:

1

2

5

8

3

G

9

4

7

10

(a) The vertical columns are I-lines through 1.

(b) The line joining 2 and 5 meets that joining 3 and 0 at
10' (the conjugate of 10); and so, in general, the line joining
any two points in a horizontal line meets the line joining any
other two, in another horizontal line and in the columns of the
first two, in the conjugate of the point not in these columns-
nor lines (2, 8 meets 4, 10 at 6'; 7, 10 meets 6, 9 at 2', and so on)..

Feb., 1916]

Hexagon Notation

149

(c) Any two points in a horizontal line are in a line with
the conjugates of those not in the line nor columns of this
selection (2, 5, 9' 10' is a line; 3, 9, b' , 7' is a line, etc.)

d The conjugates of the horizontal lines are in line with
V {V, 2', 5', 8' is a line, etc.)

Proof of (c) and (b) :

Collinear groups with (2) (in addition to that given) are
(using other hexagons in a g-point with (2) ) :

fac, eb, df (2)1 faf, ec, db (2) ]

ac, df, be (5) I /-r \ j af, db, ce (6')

ac,be,fd (10') f ^^ ' ] af , ce, bd (8)

^ac, fd, eb(9')J [af, bd, ec (7')J

as tested by sections 4 and 5.

(M)

And collinear groups with (3) are:

ffc, ae, db (3)1 fde, fb, ac (3) ]

fc, db, ea (8') 1 .^s I de, ac, bf (5')

fc, ea, bd (6) f ^^ ' | de, bf, ca (9)

[fc,bd,ae (100 J [de, ca, fb (7')

(O)

(L), (M), (N), (O) prove (C), while (L) and (M) show that
line 2, 5 meets line 3, 6 at 10', and so in same way for other
statements.

Taking the g-point conjugate to 1, and treating it the same
way as 1, we get

V

6' 5' 7'

3' 2' 4'

9' 8' 10
as is easily tested.

Thus the fifteen I-lines given by the numerical table are:

1, 2, 3, 4

1, 5, 6, 7

1, 8, 9, 10

2, 5, 9', 10'

2, 8, 6', 7'
5, 8, 3', 4'

3, 6, 8', 10'
3, 9, 5', 7'

as illustrated on the following diagram

6, 9, 2', 4'
4, 7, 8', 9'
4, 10, 5', 6'

7, 10, 2', 3'
V, 2', 5', 8'
1', 3', 6', 9'
1', 4', 7', 10'

150

The Ohio Journal of Science [Vol. XVI, No. 4,

Fig. 3. The 15 I lines and 20 g points. 10 g points and conjugates.

(49) The g-points not connected by I-lines.
In the Veronese group in (46), no line runs from the g-poinl
1 on a b c d e f (1) to 8, 9, 10, but this

'ace. bfd (8)1
< cea, dbf (10) ^^ (h)
^eac, fdb (9) J

is the point unique to (1) (See section 9).

Thus in any Veronese group, no g-point on the Pascal of
any hexagon is connected by I-lines to the g-points on the
Pascals of the hexagons of the h-point unique to the given
hexagon.

Through each point pass three Pascal lines (of different
Veronese groups), and thus the g-point 1, is not connected to
any of the g-points on any of the Pascal lines of any of the nine
hexagons unique to the hexagons of the given g-point; and no
g-point is connected by an I-line to its conjugate g-point.

Dt'pt. of Mathematics, Ohio State University.

OUTLIERS OF THE MAXVILLE LIMESTONE IN OHIO
NORTH OF THE LICKING RIVER.*

By G. F. Lamb.

(Published by permission of the Ohio Geological vSurvey.)

It is well known to those familiar with Ohio geology that
the Maxville limestone is the uppermost formation of the
Mississippian system found in the Ohio scale, that its outcrop
is limited in extent, patchy in character, and that the over-
lying Pennsylvanian beds rest upon it unconformably.

William C. Morse, in Bulletin 13 of the Ohio Geological
Survey, published in 1910, presents the most complete account
of this formation published. It is shown in this bulletin that
up to 1910 all the known outcrops of this formation occur
south of the Licking River, extending from a point a little
southwest of Zanesville, on the north, to the vicinity of Ports-
mouth on the Ohio River. It is further shown that the most
important area of outcrop lies at the north and extends from
near Zanesville southward to the vicinity of Logan — an area
about 25 miles long and 10 or 12 miles wide.

It has long been supposed that this formation once extended
to the northern part of the state and was removed by post-
Maxville pre-Pennsylvanian erosion. The supposition was
based upon the presence of lime cobblestones more or less
silicified found at the bottom of the Coal Measure basal con-
glomerate, and which were said to carry Mississippian fossils.
Since no other Mississippian limestone was known to occur
in the state, it was concluded the cobbles must have been
derived from the Maxville.

It is the purpose of this paper, (1) to point out the north-
ward extension of this limestone, (2) to throw further light on
the origin of the cobble stones, and (3) to emphasize a reason
for its absence in the northern part of the state.

The writer has found various outcrops of this limestone as
far as 40 miles north of Zanesville in a belt 10 to 12 miles wide
extending northward across Muskingum, Coshocton and into
southern Holmes County. They invariably occur in isolated

*Read before Section E of the American Association for the Advancement of
Science, Columbus meeting, 1915.

151

152 The Ohio Journal of Science [Vol. XVI, No. 4,

places, and not more than three of the outcrops could be other
than outliers.

A few of these outcrops may be described briefly. About
7 miles northwest of Zanesville on the north side of the Licking
River and about 11 miles north of the Fultonham outcrops
described by Morse, two outcrops were found well exposed
in ravines about 3^ mile apart. The limestone is bluish gray,
fine grained, compact, without prominent bedding planes and
3 to 7 feet in thickness. No fossils were found, and it appears
to be the lower division of the Maxville described by Morse.
Apparently it rests conformably upon the Logan shale, but is
overlain unconformably by Coal Measure sandstone.

It was again found in bed north of the Walhonding River,
23^ miles north of Walhonding Village and 2 miles south of
the village of Tiverton Center in northwestern Coshocton
County. There six feet of the limestone is well exposed in a
deep ravine, contains considerable iron, weathers to the color
of yellow clay — indeed almost to the yellow of ochre. The
top and bottom weather to a brown. It looks so very like a
compact yellow clay that one's first impression of it is that
it really is a bed of clay. Digging into the yellow mass 4 to 6
inches dispels the illusion by finding the familiar fine grained
light gray limestone. The upper surface as seen in the ravine
side is uneven and is overlain by 2 feet of light green mud
mingled with flinty cobbles of limestone. The mud bed
appears to be the residual material of the decomposing limestone.

Resting directly upon the mud bed is the pebbly Coal
Measure rock. This peculiar green mud carrying angular
cobble stones, and the underlying limestone weathering to an
ochre color is very like exposures found by Morse far to the
southward.

Eight miles southeast of the above exposure is the town of
Warsaw. Several outcrops occur at 1 to 4 miles north and
east of this place which range from 2 to 9 feet in thickness.
Two miles east of Warsaw an outcrop presents the ochre
weathering phase in marked degree. Four miles east of Warsaw
and () miles northwest of Coshocton in the high bluff over-
looking the junction of Killbuck Creek and Walhonding River
occurs the most easterly outcrop found. Three feet of hard
gray limestone in several layers weathering brown are exposed
and with neither top nor bottom seen.

Feb., 1916] Outliers of the Maxville Limestone 153

Probably one of the most instructive outliers found occurs
4 miles north of Warsaw and 1 mile south-west of Blissfield
on the Blissfield-Warsaw highway. The exposure occurs in
the highway at the crest of the ridge and shows 9 feet of the
limestone in many layers resting conformably upon the Logan
shale a long section of which is exposed. Resting directly
upon the limestone is a bed of sandstone 12 to 18 inches thick,
sharply undulating, and strikingly unconformable. The sand-
stone is white to gray in color, very compact, and exceedingly
hard. The limestone is well weathered, is soft, buff to yellow
in color, and contains many fossils of brachipods and fenestellid
bryozoans. When completely weathered, as seen in the road-
way nearby, it becomes an ocherous earth.

One of the most interesting facts is the presence of hard
concretionary nodules more or less silicified and definitely
embedded in the limestone. They are precisely like the
thousands of loose cobble stones seen in dozens of places where no
bed of limestone was found. The writer had believed for some
time that where beds of these loose cobbles were found, or where
they were numerous, they marked the place of the Maxville
limestone, but up to the finding of this outcrop he had no
positive evidence of their origin.

It may be pointed out that this outcrop marks the crest of a
Mississippian hill, as these patches UvSually do. North, east, and
south the Mississippian surface falls a hundred feet or more.
In a hill close by, the Lower Mercer limestone is found only
50 feet above the Maxville — an interval that is usuallv 120 to
150 feet between the Lower Mercer limestone and the base
of the Pennsylvanian.

Noting the elevation at which the various outcrops occur,
it is found they all lie in one plane very gently dipping to the
south-east. It may be stated further that the many beds of
cobble stones found at the Mississippian-Pennsylvanian con-
tact all lie in this same plane. This indicates in no uncertain
way that the cobble beds are the remains of the Maxville and
mark its place.

The most westerly point at which a bed of cobbles was
found is in Licking County, 8 miles north-east of Newark and
4 miles north-west of Hanover. The exposure is in the roadway
on the western edge of Perry Township. The stones range
in size from the fist up to 15 or 18 inches in diameter, are

154 The Ohio Journal of Science [Vol. XVI, No. 4,

generally flinty in character, weather white, and are fossili-
ferous. This description will apply to all the cobble beds
except in point of size.

The most northerly beds found occur about 5 miles south
of Glenmont in Holmes County, where the surface in places
is strewn with cobbles. At one point on top of a ridge, besides
the cobbles the soil is all a rich chocolate color. The area
is an acre or two in extent and is the residue of the
fully weathered limestone.

It is now known that the Maxville is found two-thirds of
the distance across the state with strong probability of still
further extent formerly.

Taking the Berea sandstone as a datum plane in the general
direction of the Maxville outcrop, it is found that the Berea-
Maxville interval increases northward. In Vinton County
the interval between the top of the Berea and the top of the
Maxville is about 650 feet; at Rushville, in eastern Fairfield
County, about 800 feet; at New Castle, in Coshocton County,
840 feet; near Killbuck in southern Holmes County, 870 feet;
and 20 miles north of the last point in central Wayne County
east of Wooster, 900 feet of shale and sandstone above the'
Berea does not quite reach the Maxville horizon. Northward
from Wayne County the total thickness of the Mississippian
strata decreases notably, due to greater erosion in late Missis-
sippian time. In north-eastern Ohio the Pennsylvanian beds
lie, commonly, only about 3 to 4 hundred feet above the Berea,
and in the old Mississippian river valleys, clearly defined in
this area, the Sharon Conglomerate sometimes lies but 100 feet
above the Berea.

If the plane of the Maxville be projected northward to
Cleveland with the slowly increasing interval between it
and the Berea, the Maxville would lie about 1050 feet above
the Berea.

In the light of these facts it is apparent that the Maxville
can not be found in northern Ohio, and that outcrops may not
be expected beyond northern Holmes, or central Wayne County.

It will be noted further that these figures reveal the inter-
esting fact that the Mississippian System thickens northward,
although thinest in the northern part of the state now, as a
result of greater erosion.

Mt. Union College, Alliance, Ohio.

OCCURRENCE OF CARBONACEOUS MATERIAL IN THE
GREENFIELD MEMBER OF THE MONROE

FORMATION.

Charles W. Napper.

At the Rucker quarries in Greenfield in southwestern Ohio,
is the largest and most important exposure of this member in the
Monroe formation. Above the water level of Paint Creek
there are 45 feet of stone, and quarrying has been conducted
as deep as 15 feet below this level. The entire vertical extent,
which is of the Greenfield member, is 60 feet. The rock is a
dolomitic limestone and is divided into two parts, the low^er
strata gray and the upper ones buff. The gra}^ is a hard,
solid limestone, while the buff, although firm, breaks more
easily under the hammer. In addition to the color the occur-
rence of carbonaceous material also serves to differentiate the
two parts. The Greenfield stone is of a very close texture and
with the exception of occasional masses having crevices, its
firmness, solidity and density are distinguishing characteristics.
The stone is rich in carbonaceous material which is disseminated
throughout its entire extent, as it has little opportunity to
collect in any large quantity. When the stone is freshly
broken this material gives it a bituminous odor which is a helpful
test in distinguishing this rock from other formations.

The Gray Stone. — In the gray stone carbonaceous material
is evidenced in three ways in addition to the odor test.

First. — In a thin ledge within a foot of its lowest worked
level this carbonaceous material is volatile. As pieces are
broken off it evaporates much the same as gasoline when
poured out.

Second. — Throughout the gray stone carbonaceous material
manifests itself by the profusion of carbon lines. They are as
numerous as twenty or twenty-five to the inch. Their size
is similar to that of lines drawn with a fine pen point. They do
not occur at regular intervals; one inch will be full of them,
then a clear space of a fractional part of an inch, then more
lines. When they occur close together at intervals, they
give the rock the appearance of having a banded structure.
Usually they are parallel, and not often wavy unless bending
.around a quartz-lined cavity or a nodule of sphalerite. The

'55

156 The Ohio Journal of Science [Vol. XVI, No. 4,.

rock can be split along these lines and the surfaces will show
hard, dry, carbonaceous material either solid in extent or in
patches. In the gray stone these lines are all through it,
while in the buff stone the few that occur are usually found
near the edges of the ledges.

Third. — Carbonaceous material also occurs in the gray
stone in sheets. These sheets occur at the parting line between
the ledges, especially between the strata near the contact
between the buff and the gray stone. Particularly after-
blasting these sheets can be taken out entire as large as two
feet square. The average thickness is almost 1/32 inch, and
they are sometimes as thick as 1/16 inch. When these sheets
are placed in the fire they burn with an oily, sooty flame,
leaving a thin rock stratum. The sheets are not consumed
as a shingle would be, but the carbonaceous material seems
to burn out as if the sheet were soaked in oil. This suggests
that these sheets are very thin limestone layers heavily
impregnated with carbonaceous material.

When these carbon dividing planes of the lower layers are
split they often show the obverse and reverse of the fossil
plant, Sphaerococcites (?) glomeratus Grabau. It is a ready
inference that these sheets and lines mark the beds of this
plant, from the decay of which they received their carbon
material. The objection that the lines are often noticed in
the buff stone where this fossil plant is not found can be met
by the statement that as the lines are thickest and most profuse
in the gray stone there would be the most natural place for the
distinctive preservation of the fossil. Further, the harder
texture of the gray stone which prevents the carbonaceous
material from penetrating the rock would also serve to preserve
the fossil plant distinctively and in its entirety. It also suggests
that the gray stone was built up by successive flourishing of
the plant and deposition of rock material. As the gray stone
is hard and very solid, we do not find carbonaceous material
other than as just stated, as it has no opportunity to seep
through the rock and collect in masses of "rock tar."

The Buff Stone. — The buff stone being softer, less dense and
with numerous cavities, its carbonaceous material has the oppor-
tunity to present itself more distinctly than in the gray stone.
While carbon lines do occur, yet they are never in profusion

Feb., 1916] Carbonaceous Material in the Monroe

Vol

and are to be found in only a few strata other than have been
mentioned. The buff stone is most carbonaceous where
it is nearest the gray. The odor test indicates that the buff
stone is equal to the gray in its carbon element. It also
manifests itself in three additional ways.

First. — In breaking the buff stone we frequently find that
its looser texture has permitted the carbonaceous material to
gather between the rock particles. The stone appears as
though stained with some heavy black oil or fluid.

Fig. 1. The Greenfield member of the Monroe formation, Rucker quarries,
Greenfield, Ohio.

1. Drift.

2. Buff stone, with heavy layers and carbon sheet zone toward the base.

3. Graj^ stone, with carbon lines.

Second. — Carbon sheets are more frequent and better
defined in the buff than in the gray stone. They occur between
the lower ledges; in fact, from two feet below to six or eight
feet above the contact of the gray and buff stones is the carbon
sheet zone. There seems to be a gradation from the profuse
carbon lines of the gray stone to their total absence in nearly
all of the buff. The dominant distinguishing feature of the

158 The Ohio Journal of Science [Vol. XVI, No. 4^

buff stone in this particular exposure is the almost complete
absence of carbon lines, which causes it to stand out in strong
contrast to the gray stone with its profusion of these lines.

Third. — Throughout the buff stone of this particular
exposure, but especially numerous in its heavier lower ledges,
occur "cup and cone concretions." These peculiar forms are
fully treated in another paper, but for the present study the
cavity usually present with them affords the best place for the
collection of carbonaceous material. These "concretions"
do not occur in the gray stone, and it seems that the looser
texture of the buff stone favors their formation.

From the rock surrounding the cavities the carbonaceous
material drains into them. Here the natural "rock tar" is
found. Sometimes it spreads out and fills the cavity; sometimes
it adheres to the walls of the cavity in drops as large as the end
of the little finger. This is pure, solid carbon material, hardened
and brittle; when heated it becomes waxy and burns with a
heavy, oily flame. While a rare form, Figure No. 3 admirably
illustrates how this collection does take place. The drop in the
cavity at the termination of a carbon line along which has
been the flow is conclusive evidence. Also on the sides of the
"cup and cone concretions" are lines of fracture where car-
bonaceous material accumulates. Here it appears in streaks.

Summary. — The Greenfield member of the Monroe for-
mation contains much carbonaceous material, evidenced by
odor, carbon sheets and lines, carbon stains, and solidified
"rock tar." Its close texture prevents that accumulation
necessary for a paying gas or oil rock. If its texture were open
and spongy then it might have had economic value other
than that for building and agricultural purposes.

EXPLANATION OF PLATE.

Fig. I. Occurrence of carbonaceous material in gray stone. "Carbon
sheets" occur between layers nearest contact with buff stone in which they are
far more numerous. "Carljon lines" are profuse throughout the gray stone and
serve to distinguish it.

Fig. 2. Occurrence of carbonaceous material in buff stone. Upper layer
stained with carbon material; lower layer to show collection in cavities and in
"cup and cone" concretions.

Fk;. 3. "Rock tar" in buff stone. Collection and How liave been along
carbrm line, terminating in carbon drop in cavity.

Ohio Journal of .Science.

Vol. XVI, Plate III.

Tiqure. 1. a.carhon sheets; h. Carbon //'nes

r -^

-z .- ^--

^J^^:^

^5?

-^ ^ -r^^2;^^g>^^r£^^^«:r:^/ ^: -

s

Tig are. 2.

J'*'

6

n^ure. 3.

Charles W. Napper.

Date of Publication, February 25, 1916.

THE

Ohio Journal of Science

PUBLISHED BY THE

Ohio Statk University Scientific Society
Volume XVI MARCH, 1916 No. 5

TABLE OF CONTENTS

CoGAN — Contribution Towards Our Knowledge of the Homoptera of South

Africa 161

HOMOPTEROUS STUDIES. PART I.

Contribution Towards Our Knowledge of the Homoptera

of South Africa.

Eric S. Cogan, M. A.

introduction.

The systematic treatment of the Auchenorrhynchous Hom-
optera of South Africa has received but Httle attention from
entomologists and naturaHsts, with the result that the worker
or investigator finds himself confronted with what may be
termed a pioneer task. Of all the orders of insects in South
Africa, the Hemiptera and particularly the suborder Homoptera
have been studied the least. The list of described species, at
all events for the Auchenorrhynchous Homoptera, would
scarcely number more than one hundred. The Cicadidae
and Fulgoridae are perhaps the best known, yet our knowledge
of these two large families is far from complete. The Mem-
bracid^ have received but passing comment, while the Cerco-
pidas and Jassoidea are scarcely known at all.

Through the courtesy of Professor Osborn of the Ohio State
University, the writer was afforded an opportunity to study
a series of Cercopids and Jassids, which had been consigned to
him for study by Mr. Mally, of the Department of Agriculture
in the Cape Province. Except in a few cases where the speci-
mens had faded a little, the collection was in a good state of

i6i

162 The Ohio Journal of Science [Vol. XVI, No. 5,

preservation. In all some thirty-eight forms were studied
and the results are embodied in the following pages.

It will be seen that the generic descriptions have been
given; and this is done in view of the fact that the writer here
wishes to lay the foundation for future extensive study of the
families concerned. In some cases species have been rede-
scribed fully, because the original descriptions are brief, totally
inadequate, and not readily accessible to the average worker.
Where species are described as new the writer has endeavored to
present, as far as possible, accurate drawings to supplement
the descriptions. On account of the growing importance of the
ecologic and economic relationships of Insects, a short dis-
cussion of these two phases of study is given.

The types of new species will be deposited in and numbered
at the South African Museum, Cape Town.

ACKNOWLEDGMENT.

I desire here to express my sincere thanks to Professor
Osborn, of the Department of Zoology and Entomology of the
Ohio State University, for much valuable suggestion and
criticism, and for facilities placed at my disposal; to Mr.
Hewitt of the Albany Museum, for the loan of specimens
and to my father, Mr. R. J. Cogan, for material forwarded
to me for study.

HISTORICAL.

The earliest references to the Homoptera of South Africa
are contained in Linne's work, Systema Natura, Ed. X, pub-
lished in 1758, wherein the descriptions of four Cicadas and a
Fulgorid are contained. During the same century, Fabricius
was responsible for the descriptions of some few forms which
had been collected by the early voyagers and explorers of the
Cape of Good Hope. Among others De Geer may be mentioned
as contributing to our knowledge during the same period.
The first half of the nineteenth century was not productive
of many workers in the suborder — Germar, Westwood, Guerin,
Anyot and Serville, Thunl)erg and Burmeister, were perhaps
the most prominent. But the year 1850 saw the appearance
of Walker's List of Homopetra in The British Museum and
during the succeeding two decades, considerable work was done
by Stal, Signoret and Westwood.

March, 1916] Homopterous Studies. Part I 163

Walker's List with Supplement was completed in 1858, and
contained the descriptions of numbers of South African Genera
and species. Concerning his work. Distant has written:
"Walker was a prolific and somewhat hasty writer, and the
value of his work was very uneven. His name is however
associated with and never can be excluded from the annals
of the South African Homoptera, or scarcely from those of
any other region : he was a pioneer, though his survey required
and still requires much supervision."

Stal's monumental work, Hemiptera Africana appeared in
1866, and is held today as the most comprehensive work ever
accomplished on the order, so far as South Africa is concerned.
Of him Distant writes: "Stal built on his own foundation, he
possessed a genius for taxonomy; what Lacordaire did for
Coleoptera, he more than achieved for the Rhynchota and his
work may be further elaborated, but will never be super-
seded. He was a severe critic of Walker's work and even
proposed its suppression." Stal wrote almost exclusively in
Latin with a style all his own, and it has been the lot of many
Hemipterologists to experience difficulty in translating many
of his expressions. He apparently collected in South Africa,
although the majority of his work was done on Museum
material.

Associated with the names of Stal and Walker may be
mentioned Signoret, the French collector and taxonomist.
During the years 1853 to 1856, he published in the Annals
of the Entomological Society of France, quite a number of
descriptions of South African Homoptera, chiefly of the family
Jassidae. Later (1880), his "Essai sur les Jassides" appeared.

Of the more recent workers and investigators, the names of
Distant (Rhynchota), Mehchar (Homoptera), Karsch 1890,
(Fulgoridas) , Buckton 1903, (Membracidas), Schouteden 1901,
(Cercopidas), and Jacobi 1904, (Cercopidae), stand out prom-
inently. Distant is perhaps the highest living authority on the
Homoptera of South Africa and has contributed many valuable
works on the group. Chief among these may be mentioned his
"Synonymic Catalogue of Homoptera," his "Insecta Trans-
vaaliensia, " and many papers in the Annals and Magazine
of Natural History. Melichar's work has been restricted
somewhat to the German East African province, where he has
collected extensively and described numbers of forms.

164 The Ohio Journal of Science [Vol. XVI, No. 5,

With the rapid development of Agriculture in the South
African provinces, more attention is being paid to the study
of Entomology and since a knowledge of systematic work is
indispensable to the economic worker, the study of the Hemip-
terous order is receiving more attention. The Homoptera will
necessarily come in for their share of study and one may predict
a healthy development in the near future of our knowledge of
this group.

ECONOMIC.

The development of the study of Economic Entomology
has brought to light the fact that many of the supposedly
insignificant and inconspicuous forms of insects are in reality
responsible for a great deal of damage to the crops of man.
During recent times attention has been paid to the investigation
of many Homopterous insects with the result that the Jassids
have been found responsible for a great deal of injury to grains,
grasses and cereals; besides native grasses, plants and trees.
Although as yet none of the Auchenorrhynchous Homoptera in
South Africa have been proven to be of great Economic Impor-
tance, it would be unsafe to say that such would always be the
case. Distant in his Insects Transvaaliensia, points out that
"as many of the species generally referred to as " Leafhoppers "
by American Entomologists, are undoubtedly injurious to
several trees and crops, a knowledge of them, however partial, is
of economic importance." Osborn further states that "the
leafhoppers affecting the cereal and forage crops constitute a
very constant factor and the extent of the drain on such crops is
doubtless much greater than is appreciated."

Entomological work in the United States and territories
has revealed the depredations of many members of the Hom-
opterous suborder: thus the Periodical Cicada (Cicadidae), the
Buffalo Tree-Hopper (Membracidas), the Sugar Cane Leaf-
hopper (Fulgorida}) in Hawaii, and the many Froghoppers
(Cercopidffi) and Jassids (Jassoidea), may be cited as examples
of the general importance of the group from an economic
standpoint. Records of extensive injury to crops by members
of the superfamily Jassoidea are obtainable in the United
vStates — thus Deltocephalus inimicus, Athysanus exitiosus,
Dr^eculacephala mollipes and D. reticulata, Agallia sanguino-
lenta, and Cicadula G-notata, constitute in some parts a great

March, 1916] Homopterous Studies, Part I 165

enemy to the cultivation of cereal and forage crops. Empoasca
mali on Apple and Typhlocyba comes on Grape may also be
mentioned to show the effect on plants other than grasses and
cereals.

The Jassoidea and Cercopidae are not restricted to grasses,
but are equally formidable in their attacks on fruit trees,
garden crops and shade or forest trees. Although their attacks
are not as prominent or apparent as those of the Locusts or
Scale Insects in South Africa, yet by their inestimable numbers
they are considered to account for much of the trouble, which
is usually ascribed to other causes.

Their method of attack is restricted almost entirely to the
sucking of the plant juices and sap, thus causing a general
wilting of the parts affected. The leaves and younger stems
are especially affected and the result is generally seen in the
small brown spots, indicating the punctures of the insect's
"beak." Where immense numbers of these minute insects
attack a crop, it can easily be seen that the incessant and
constant drainage of the sap will result in some material loss.

As pointed out before, none of the South African leafhoppers
have yet proven to be of great economic importance, but the
general distribution and common occurence in meadows and
pastures of Athysanus capicola makes it a very suspicious
species. Added to this, the six-spotted leafhopper, Cicadula
6-notata is now reported from the Cape Region and when one
considers its work in North America and Europe, it would not
be unfair to expect a similar state of affairs in South Africa.

The practice of burning the grass or veldt, is one which
though not very strongly recommended by the botanists,
nevertheless, serves to keep down the grassfeeding species of
Jassids. Owing to the nature of farming in South Africa, the
control conditions must necessarily be of a restricted variety,
and local more than general methods recommended.

ECOLOGIC.

Osborn states that "the leafhoppers constitute one element
in a very complex relation of plants and animals, including
birds, mammals, reptiles, toads, insects and spiders, etc., and
it is only by the recognition of this relation that we can offer
any adequate explanation of their proper place in nature, and
of their importance in the economy of cultivation. Primarily

166 The Ohio Journal of Science [Vol. XVI, No. 5,

they are associated with certain kinds of plants upon which
they depend for their sustenance and the abundance of leaf-
hoppers will be affected, necessarily, by the abundance of the
food plant and its availability as food material. An undue
increase of the leafhoppers, which should result in the dim-
inution of the food supply, must necessarily affect the possibili-
ties of multiplication and cause a certain reduction in the
number of the insects. This is by no means the only statement
of conditions, as, aside from these two forms which may be
associated in the same area, a large number of other organisms,
both plant and animal, will affect the problem. The occurrence
of different birds and predaceous insects which prey upon the
leafhoppers will naturally reduce their numbers and to that
extent favor the plants which serve as their food, whereas
the presence of herbivorous animals, grasshoppers, cutworms,
etc., serves to reduce the available food supply. Aside from
these dominant forms, there are also various fungus parasites
which attack both insects and plants and which play their
part in the complex, of which the leafhoppers are such a con-
spicuous element. Furthermore, the minute insect parasites
which attack the leafhoppers add their part, tending to keep
the latter reduced in numbers."

Some of the points here mentioned are well borne out in
South Africa; thus the increase in vegetation from the west to
the east, is followed by a great increase in the numbers of forms,
with the result that the Eastern Province and Transkei terri-
tories (the Caffraria of Stal), contain a greater number of
individuals. It must be emphasized here that but mere
passing comment on the ecological relations can be given,
as our knowledge of the group precludes any but bare state-
ments of recorded observations. The presence in South
Africa of a fauna restricted almost entirely to the dry Karroo
region, makes the study of ecology an interesting one. Added
to this the subtropical character of the climate and vegetation
of Natal, and the northern regions, one is confronted with a
variety of conditions scarcely paralleled on any other continent.
Many of the endemic genera and species are restricted almost
entirely to the Karroo region.

The relations of the higher animals to the Homopterus
fauna can only be touched on. While it is known that herbivo-
rous animals in foraging, arc likely to swallow the eggs, yet the

March, 1916] Ilomopteroiis Studies. Part I 167

matter is of minor importance. As with the locusts, the
birds must necessarily constitute some check on the increase
of the fauna. The writer recalls the swallows feeding exten-
sively on Jassids in the district of Albany. Another interesting
fact is recalled, and that is the habit of the common "Butcher
Bird," which catches and impales various insects, such as
Grasshoppers, Cicadas, Fulgorids and Jassids, on barbed wire
fences and on thorns of trees such as the "Mimosa." Distant
records that "birds are dangerous to Cicadan life," and further
reports having seen a Cicada, Platypleura diversa Germ, eaten
by spiders. Ross records the eating of Quintilia carinata Stal
by a mantis {Miomantis fenestra Fab.). Near Rustenberg
he observed CaUipsaltria longula Stal being attacked by a
Cicindelid beetle. Bell-Marley writes of an interesting inter-
relationship existing between a Membracid Oxyrhachis tarandus
Fabr. and certain small red ants; the cause of the association
being the secretion of honey dew by the Membracids.

The protective resemblances borne to plants and flowers
by many African Homoptera, constitute an interesting associa-
tion and are worthy of mention here. Cephaleliis infiimatiis
is perhaps the best and most striking example, and the case of
mimicry is mentioned under that insect later. Distant records
a resemblance to twigs and branches by a Cicada, Platypleura
haglundi Stal, and Ross attributed the difficulty in collecting
Platypleura marshalli Dis. to its resemblance in color to the
"mopami" tree. Hinde has drawn attention to the resem-
blances borne by Plata nigrocincta Walk, to flowers of a plant
in East Africa.

While many interesting ecological facts await the investiga-
tor, it seems to the writer that none too much stress can be
laid on the importance of such study. The various predaceous
and parasitic insects must necessarily be studied before we can
obtain any definite information on the ecological relationships.

BIBLIOGRAPHY.

Amyot & Serville. Histoire naturelle des Insectes Hemipteres. (1843).

Atkins. Journ. Asiat. Soc. Beng. LIV. (1885).

Bell-Marley. Zoologist. 4. XVII. (1913).

Blanchard. Histoire Naturelle des Insectes. (1840).

Bennett, E. T. Proc. Zool. Soc. Lond. (1833).

Boheman. Kongl. Vetenskaps-Akademiens Handlingar. (1838).

Buckton. Monogr. of the Membracida;. (1901-1903).

Burmeister. Handb. Ent. ii. (1835). id. Genera Insectorum (1838-1846).

Butler. Cist. Entom. 1. (1874).

168 The Ohio Journal of Science [Vol. XVI, No. 5,

Coquebert. 111. Iconograph. Insect. (1799).

Drury. Illustrations of natural history. Ed. XII. I. (1773).

De Geer. Mem. pour serv. a I'hist. nat. Ins. (1778). id (1783).

Distant. Trans. Ent. Soc. Lond. (1878, 1881, 1893). Monog. Orient. Cicad. (1899).

Ann. Mag. Nat. Hist. (1897, 1899, 1905, 1906, 1907). Trans. Philos. Soc. South

Africa XVI. (1906). Synony. Cat. Homop. (1906). Faun B. I. Rhynch. IV.

(1907). Entom. Monthly Mag. 2. XVIII. (1907). Records Albany Mus. II,

(1907). Zoologist 47. (1914).
Fairmaire. Revue de la tribu Membracides. (Ann. Ent. Soc. Fr. 2. IV. 1846).
Fabricius. Entomologia systematica IV. (1794). Mantissa insectorum ii. (1787).

Spec. Ins. II. (1781). Systema Rhyng. (1803). Ent. Syst. vSuppl. (1798).

Syst. Ent. (1775).
Germar. Magaz. der Ent. III-IV. (1818). Entom. Arch. Thon. ii. (1830). Silb.

Rev. Ent. ii. iii. (1834-35). Revue Ent. II. (1836).
Gerstaeker in v. d. Decken Raise III. XVII. (1873).
Gray in Griffs. Animal Kingd. Ins. (1832).
Guerin. Voy. Coq. Ins. (1838). Ic. Regn. an Ins. (1838). in Lefroy's Voy. en

Abyssinia Ins. (1849).
Hinde. Trans. Ent. Soc. Lond. (1902 and 1906).
Jacobi. Hom. aus Nordost-Afrika gesam. v. O. Neuman. (Zool. Jahrb. XIX. 1904).

Ueber Ostafrik. Homop. (Sitz. Berl. Ges. Nat. Berlin, 1904). Neue Zikaden

V. Ostafrika. (Sitz. B. Ges. Nat. Freunde Berl. 1910). Wiss. Ergelr. Schwed.

Zool.-Exped. Kilimandjaro, Meru und Deutsch Ostafrika. No. 12. (1910).
Karsch. Beit. z. Kenn. der Singcikaden Afrik. u. Madagascar. (Berl. Entom.

Zeitschr. XXXV. 1890). Entomologische Nachrichten XXI. (1895).
Kirby. Trans. Ent. Soc. Lond. (1894).

Lallemand. Diag. der Cercop. Air. nov. (Ann. Soc. Ent. Belg. 54. 1910).
Lepeletier et Serville. Enc. Meth. X. (1825).
Linne. Sj^stema natura X. (1758). Cat. Ins. rar. (1763). Mus. Lud. Ulr. (1764).

Svst. Nat. XII. (1767).
Melichar. Monog. d. Ricaniiden. (Ann. K-K. Nat. Hofmus. Wien. XIII. 1906).

Monog. d. Acanaloniiden u. Flatiden. (Ann. K-K. Nat. Hofmus. Wien. XVI.

1901). Wien. Ent. Zeit. XXIV. (1905). Monog. d. Issiden. (Abh. K-K. Zool.

Bot. Ges. Wien. III. 1906). Casop. Ceske spol. entom. acta Soc. entom.

Bohemiae Rocn. (1908).
Schaum. Encyclop. d. Wissensch. u. Kunste v. Ersch u. Gruber I. (1850). Gen.

d'ins. Artr. (1852). Ber. Ak. Berl. (1853). in Peter's Reise nach Mossambique

Ins. (1862).
Schmidt. Stettin Ent. Zeit. LXVII. (1908). id. LXXIV. (1913).
Schumacher. Wien. Ent. Zeit. Jahrg. 31. (1912).
Signoret. Ann. Ent. Soc. Fr. (1850, 1853, 1860, 1879-80). Ent. Arch. Thon. II.

(1853). Essai sur les Jassides in Ann. Ent. Soc. Fr. (1877-78). Revue Iconog.

Tettigon. in Ann. Ent. Soc. Fr. (1853-55).
Schouteden. Hem. Afr. (Ann. Ent. Balg. XLV. 1901).
Spinola. Ann. Ent. vSoc. Fr. VIII. (1839).
Strand. Entom. Rundsch. Jahrg. 22 (1910). id. 28. (1911).
Stal. Ofv. Vet. Akad. Forh. (18.54, 1856, 1858). Kongl. Sven. Freg. Eug. Resa.

(1858). Ber. Ent. Zeitschr. III. (1859). Ent. Zeit. XXIV. (1861, 1863). Ann.

Ent. Soc. Fr. (1862). Ent. Trans. 3. I. (1863). Rio Jan. Hem. IV (1862). Hem.

Afr. IV. (1866). Hem. Fabr. ii. (1869).
StoU. Represent, des Cigales ef Punaises (1781-1790).
Thunberg. Hem. Rostr. Cap. I. (1822).
Walker. Cat. Homop. Brit. Mus. I-IV. (1850-52). Suppl. (1858). Ins. Saundersi-

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Westwood. Trans. Linn. Soc. XIX. (1842). id. XVIII. (1841). id. XXVIII. (1851).

Ann. Mag. Nat. Hist. 2. VII. (1851).

March, 1916] Homopterous Studies. Part I 169

FAMILY CERCOPID^.

This interesting family is characterized by the shape of the
hind tibice, which are cyHndrical and armed with two spines on
the outer side, one near the base, and the other a httle beyond
the middle, the former once and the latter twice as long as the
tibiae are wide. Tibiae and first two joints of the tarsi termi-
nated with a crescent-shaped row of spines, and the third joint
with a bifid claw. Frons usually tumid and convex or com-
presso-produced. Antennae inserted between the eyes. Two
ocelli located on the disc of vertex. Pronotum sixangular or
trapeziodal; scutellum triangular or rhomboidal. Elytra cor-
iaceous, more or less covered with a fine pubescence.

The family comprises the well-known "Cuckoo-spit,"
"Frog-hoppers," or "Spittle Insects," so called from the
frothy enveloping exudate in which the early history of the
insect is spent. The chief works on this family are those of
Walker, Stal, Distant, Schouteden and Jacobi.

Table of Subfamilies of Cercopidae.*

1. Anterior margin of the thorax straight, eyes equally as long as broad

Cercopida Stal.

2. Anterior margin of the thorax rounded or angular: eyes frequently transverse.

Aphrophorida. Stal.

SuBF. Cercopida Stal.

Synopsis of Genera.*

A. Front without a longitudinal carina.

a. Front with a longitudinal sulcus Rhinaulax. A. & S.

AA. Front with one or more than one longitudinal carina at middle. Front with
one carina.

b. Carina weak, not well developed Locris. A. & S.

Genus Rhinaulax A. & S.

Head broad, the front convex and broadly flattened or
impressed from the middle of the base to beyond the middle of
the length. Ocelli remote from the eyes. Antennae three-
articulate, extending out almost from the sides of the head.
Thorax truncate before the base of the scutellum. Scutellum
equilateral.

*Adapted from Stal.

170 The Ohio Journal of Science [Vol. XVI, No. 5,

Rhinaulax analis Fabr.

Cercopis analis, Fabricius. Ent. Syst. IV. 49. 7. (1794).

id. Syst. Rhyng. 93. 23. (1803).
Cercopis bicolor, Fabr. Ent. Syst. Suppl. 523. 11. (1798).

id. Svst. Rhvng. 93. 26. (1803).
Cercopis trifiirca. Thunb. Hem. Rostr. Cap. 1. 4. (1822).
Tetligonia bicolor, Thunb. Hem. Rostr. Cap. 1. 7. (1822).
Rhinaulax maculipennis, Am. & Serv. Hist. Hem. 561. (1843).
Rhinaulax analis Stal. Hem. Afr. IV. 65. (1866).
Rhinaulax analis Distant. Ins. Transv. IX. 227. (1908).
Rhinaulax analis Walk. List. Hom. B. Mus. Suppl. 667. (1851).

General color black, with the elytra red, or varied. Length

of female and male, 8 mm. Breadth 3 mm.

Vertex black, short, the anterior margin rounded, three times as
broad as its length. Ocelli black, located closer to one another than to
the eyes. Eyes oval, grayish black in color. Face black, the frons
tumid, flattened on the middle, with numerous transverse furrows;
clypeus produced, flat; rostrum long, black. Pronotiun black, finely
punctate, with indistinct rugae, much broader than the head; a median
longitudinal line; length about two and a half times as long as the
vertex; convex above. Scutellum long, the apex sharp, depressed on
the middle, with indistinct transverse striations; not quite as long as
the pronotum. Sternum of thorax black. Elytra red at base, yellowish
towards the apex black along the inner margin. Abdotnen black above,
beneath black, with the posterior edges of the segments red; red at base.
Genitalia of male rather obscure; last ventral segment about twice as
long as the penultimate; plates long, rounded.

Habitat: Caffraria (Castelnau), Cape Colony (Distant),
Post Elizabeth, Simonstown (Oxford Museum), Rosebank
C. P. (Brain).

Rhinaulax analis war. bicolor.

Black, with the elytra yellowish green, with black along the inner
margin and brownish on the apical area. Abdomen black, with yel-
lowish at base. Last ventral segment of female reddish; pygofers long
and flattened, the ovipositor a little longer.

Habitat: Newlands, C. P. (Brain) and as above.

This species is most variable, Stal having described no less
than three different varieties. The variety 'bicolor' seems to
have a very general distribution over Cape Province, but is as
yet not recorded from the neighboring provinces.

Genus Locris Stal.

Frons very tumid, convex, prominent in front and below;
viewed from the side, neither compressed nor angular in form
unless very obsolete; provided with a distinct carina on the

March, 1916] Homopterous Studies. Part I .171

middle. Antennae very short, ocelh further removed from the
eyes than from one another. Base of thorax truncate. Scutellum
subequilateral.

"According to our present knowledge, this is distinctly
Ethiopian Genus. It is also a most extensive one, some forty
two species having already been described. As pointed out by
Stal, two subdivisions of the genus are possible by the character
of the surface of the pronotum. " (Distant).

A. Pronotum very coarsely punctate and posteriorly rugose.

B. Pronotum distinctly punctate but not posteriorly rugose.

A. Locris arithmetica Stal.

Locris arithmetica Stal Hem. Afr. IV. 58. (1866).

Monecphora arithmetica Walk. List. Hom. B. Mus. 675. (1851).

Locris arithmetica, Dist. Ins. Transv. IX. 227. (1908).

General color bright red, interspersed with black marks

on the head, thorax and elytra. Ventral color black, the whole

covered with a dense pubescence. Length of both male and

female 12.5 mm. Breadth 4.5 mm.

Head small, much narrower than the pronotum; vertex produced
anteriorly, its length about equal to the width across the eyes; anterior
half of vertex red, the posterior, dense black. Eyes large, dark gray.
Frons black, red at the anterior margin of the head, very tumid; longi-
tudinal carina rather poorly developed; numerous deep transverse
furrows; cheeks very small and rostrum long. Pronotum a little more
than one and a half times as long as the vertex, narrow next the head,
widening considerably towards the elytra; black on the anterior half,
except along the lateral margins which are red; the red band continuous
across the middle. Posterior margin black; pronotum very convex,
finely punctate, the punctations occupying fine rugce on the posterior
half; anterior half with numerous small depressions or irregular pits;
lateral posterior angles of the pronotum obtuse, the posterior margin
inwardly rounded; lateral edges red, black beneath and shining. Scu-
tellum jet black. Elytra bright red, marked characteristically with six
large black spots, two near the base, one on the claval area, another on
the corium, a smaller spot on the claval suture, just before the apex,
one larger at the apex, and the last on the middle of the elytron.
Venation rather indistinct. Hind wings slightly lurid. Abdomen
brown above, beneath black but reddish at base, the posterior edges of
the segments red. Legs black at base, the tibia bright red and the
tarsi black. Posterior tibi« with the median spine well developed.
Genitalia indistinct.

Habitat: Transvaal, Pretoria (Distant), Johannesburg,
(Cruger, Brit. Mus.), Boksburg (Kaessner), Natal (Mansell
Weale), Durban (Bell-Marley), Howick (Cregoe), Bechuana-
land, Omaramba (Erikson), Kaffraria, (Castelnau, Oxford Mus.)

172 The Ohio Journal of Science [Vol. XVI, No. 5,

Tegwani (Brain), Debe Nek (Brain), Metabele Land (Gates,
Oxford Mus.), Mashonahand (Salisbury, Marshall), Cape
Colony (Mansell Weale), King Williamstown (Barrett). "Africa
meridionalis occidentalis " (Stal).

B. Locris transversa Thunb.

Cercopis transversa, Thunberg. Hem. Rostr. Cap. 1. 4. (1832).
Monecphora pha'nicoptera, Walk. List Horn. Brit. Mus. 111. 676. (1851).
Monecphora ftiscicoUis, Stal. Ofv. Vet. Ak. Forth. 95. (1855).
Locris transversa, Stal. Hem. Afr. IV. 61. (1866).
Locris transversa, Dist. Ins. Transv. IX. 228. (1908).

Black with red on the head and thorax. Elytra red,

yellowish towards the apices. Length 8.5 mm. Breadth

3.5 mm.

Head not as wide as the pronotmn, rather sharply pointed; anterior
and lateral margins of vertex red, black on the middle and posterior
margins between the eyes. Eyes grayish black. Width at eyes a
little longer than the length of the vertex. Face very tmnid, the frons
black with the carina red ; numerous transverse furrows ; clypeus bright
red, rostrum long, black at the tip. Cheeks narrow, black., with the
edges red. Pronotum much wider than the head, the anterior margin
straight, red; a large black transverse band behind the anterior margin,
a median red band and the lateral edges red; posterior black; finely
punctate and pubescent. Width about twice the length; length about
one and a half times the length of the vertex. Sterntmi of thorax red.
Scutellum very small, black, and very pubescent. Elytra bright red,
the veins showing yellowish, towards the apical area lighter; hind wings
brownish, paler towards the base, the veins brown, and red near the
base. Abdomen above black, the posterior edges of the segments red;
beneath black, red at base, and on edges of the segments. Genitalia
of female red; the last ventral segment dark red, longer than the
penultimate, and deeply emarginate. Legs dark red.

Habitat: Natal (Mansell Weale), Durban (Leigh, Gxford
Mus.), Isipingo (Marshall), Delago Bay (Monteiro), Kaffraria
(Stal), Cape Colony (Drege, Brit. Mus.), East London (Brain),
Uitenhage (Oxford Mus.).

Locris rubida Stal.

MoHccphora rubida Stal Ofv. Vet. Ak. Forh. 96. (1855).
Monecphora postica Stal Ofv. Vet. Af. Forh. 96. (18.55).
Locris rubida Stal Hem. Afr. IV. 61. (1866).
Locris rubida Dist. Ins. Transv. IX. 228. (1866).

Color jet black, the elytra dark red, except the apical

area. Black below. Length 10.5 mm. Breadth 3.5 mm.

Head very small, rounded anteriorly, the vertex black with a trace
of red on the side margins before the eyes; length about equal to the
width across the eyes, very pubescent. Face black, the frons very

March, 1916] Homopteroiis Studies. Part I 173

tumid, with a median carina and numerous transverse furrows; a
trace of red on the rostrum. OcelH very small, eyes black. Pronotum
strong, black, finely punctate, the lateral margins faint red, beneath
black. Scutellum black, about one third the length of the pronotum,
which is more than twice as long as the vertex. Elytra red, apices
black. Hind wings smoky at apices, lighter towards the base. Abdo-
men above black, the posterior edges of the segments red; beneath black
with red for the base and posterior edges of the segments. Female
genitalia — last ventral segment not quite as long as the penultimate;
pygofers rounded, short; ovipositor long. Legs black.

Habitat: Natal (Mansell Weale), Durban (Marshall),

Kaffraria (Castelnau, Oxford Mus.), N. W. Rhodesia, Kambove

(Neave), Cameroons (Escalera), Cape Province, Fort Beaufort

(Brain).

SuBF. Aphrophorida Stal.

Synopsis of Genera.*

A. Pronotum quadrangular.

Scutellum a little longer than broad: anterior margin at lobes of vertex

acute: apices of elytra narrow Cordia

AA. Pronotum sexangular.

Scutellum a little alonger than broad; anterior margin at lobes of vertex

sulcate Philaenus

Scutellum much longer than broad; pronotum broader than the head.

Poophilus

Genus Cordia Stal.
Head rounded or angularly rounded, with the anterior
margin acute, at least to the lobes of the vertex. Front trans-
versely striate. Lateral angles of the pronotum acute. Elytra
suboblong, the apex a little narrow, and the lateral margins
subparallel. At present this genus is only known from the
Ethiopian Region (Distant).

Cordia peragrans Stal.

Cordia peragrans Stal. Hem. Afr. IV. 78. (1866).

Ptvelus peragrans Stal. Ofv. Vet. Ak. Forh. 97. 10. (1855).

Cordia peragrans Dist. Ins. Transv. IX. 223. (1908).

Grayish straw colored. Length 5.75 mm. Width 2-2.25 mm.

Head flat, brown in color, and covered with a fine gray pubescence,
wider than the pronotum at eyes, and longer than half the length of the
pronotum. Ocelli brown, as far apart from each other as from the
eyes. Anterior margin of the head fiat, rather sharp ; two black spots on
the face below the anterior margin of the head, and located midway
between median sulcus and the antennae. Face densely pubescent.
Rostrum black. Eyes dark steel gray. Pronotum fiat, twice as broad as
its length, finely punctate, the punctations arranged in fine rug^e, very

*Adapted from Stal.

174 The Ohio Journal of Science [Vol. XVI, No. 5,

pubescent. Distinct longitudinal median line, on the pronotum, and
two irregular impressions on the anterior half located behind the eyes;
two more irregular marks, situated towards the median line, also on the
anterior half. Scutellum brown, with gray pubescence, not quite as
long as the pronotum. Sides of thorax brown. Elytra for the most
part gray, brownish at the base; veins distinct brown; a black distal
spot behind the middle, situate at the anastomosis of two cellular areas;
apex of elytron almost transparent. Abdomen above dark brown to
black, the margin lighter; beneath brown with a tinge of red; legs light
brown, tips of tarsi black. Genitalia-female-last ventral segment
short, notched at the middle; plates longer than last ventral segment,
narrow; p^^gofers short and stout, with a distinct reddish tinge, very
pubescent; ovipositor black, much longer than the pygofers.

Habitat: CafTraria (Stal), Cape Province (Stal), Transvaal
Province (Distant), Zoutpansberg (Kaessner) and Selati River
(Albany Museum).

Cordia albilatera Stal.

Cordiaalbilatera, Stal. Hem. Afr. IV. 79. (1866). Distant Ins. Transv. IX. 223.

X. Tab. XXII. Fig. 9a. (1908-10).
Ptyelus albilatera Walk. List Horn. B. Mus. 723. (1851).

Grayish stramineous, covered with a pale down. Length

5.5. mm. Breadth 2 mm.

Head brownish not pubescent, a little wider than the pronotum at
the eyes; vertex not quite as long as the pronotum. Ocelli closer to one
another than to the eyes; anterior margin of head angularly rounded.
E^^es long, wide, steel gray in color. Face a dark brown, darker than
the vertex, pubescent; clypeus lighter in color, lorae brown, cheeks
much lighter. Pronotum twice as wide as its length flat, finely ptmctate,
pubescent, and rugose on the posterior half; anterior margin well
rounded; faint irregular impressions on the anterior half, midway
between the median line and the lateral margins. Scutellum much
longer than broad, with a distinct whitish longitudinal ridge on the
middle; apex shar]3ly pointed. Elytra brownish, cinereous, very
pubescent, the veins showing as dark brown ridges; apices well rounded,
costal margin grayish; small black distal spot behind the middle situate
at the anastomosis of two cellular areas; punctulate. Abdomen above
black, the jDosterior edges of the segments and the lateral margins yel-
lowish brown; beneath light brownish yellow. Male genitalia — last
ventral segment rather short, slightly notched at iniddlc; plates longer
than the ultimate ventral segment; pygofers rather long, and narrow,
the tips blackened. Legs light yellowish brown, the tips of the spines
black.

Habitat: Transvaal, Zoutpansberg (Kaessner), Natal
(Mansell Weale), Cape Colony (Stal), Grahamstown (Albany
Mus.).

March, 1916] Ilomopteroiis Studies. Part I 175

Genus Philaenus Stal.

Head angular, anterior margin of lobes of vertex obtuse,
sulcate; apex of clypeus a little produced; rostrum two-jointed,
reaching beyond the middle coxae. Elytra oblong in general
outline, the side margins subparallel, with the apices rounded.

This genus is widely distributed. In his work on the
Transvaal forms. Distant includes Philaenus under Ptyelus.

Philaenus caffer Stal.

Ptyelus caffer, Stal Ofv. Vet. Ak. Forh. 250. (185.5).

id. Eug. Resa. Hem. 287. (1858).
Ptyelus caffer, Dist. Ins. Transv. IX. 221. (1908).
Philaenus caffer, Hem. Afr. 78. IV. (1866).

General color varies, usually a grayish straw or yellowish.

Length 5-5.5 mm. Breadth 2 mm.

Vertex produced, rounded at apex, the disc fiat, densely pubescent,
the length longer than half the distance between the eyes and equal to
about more than one-third of the width across the eyes. Frons swollen,
convex, a little wider at the base than next the vertex, the sides sub-
parallel, about twice as long as the width next clypeus; the latter is
roughly triangular in shape, and sharply produced; lorae almost as wide
as the clypeus, gense angular; point of insertion of the antennae dark
brown; tip of rostrtmi black. Pronotum lighter in color than the head,
covered with a grayish pubescence, with four blackish spots on the
anterior half, two rather distinct, alongside the median line, and the
other two indistinct, near the lateral margins. These spots, however
vary in different fomis. Anterior margin broadly rounded between
the eyes; length a little longer than the vertex and longer than half the
width of pronotum. Surface of pronotum finely punctate. Scutellum
a little more than half the length of the pronotum. Elytra lighter than
rest of the body, the veins distinct, showing as brown ridges, six apical
cells, and three anteapicals, the middle cell of the latter shorter than
the other two; apices rounded, a little narrower than on middle.
Abdomen above brownish, beneath brownish black, in some cases pure
black. Legs light yellowish. Genitalia — female; last ventral segment
rather short, pygofers oval, broad, not as long as ovipositor. Male
ultimate ventral segment twice as long as the penultimate, the posterior
margin concave, plates a little longer than last segment.

Described from four males and one female.
Habitat: Cape Colony (Stal), Cape Province (Distant),
Darling, C. P., (Mally).

Philaenus hottentoti n. sp.

General color yellowish brown, form similar to P. caffer

Stal, but a little stouter. Length 6 mm. Width 2 mm.

Head yellowish, broad; vertex angularly rounded, two black spots on
the anterior margin, located on the middle close to one another; posterior

176 The Ohio Journal of Science [Vol. XVI, No. 5,

margin slightly convex on the middle, giving the ocelli a raised appear-
ance; thin black transverse line on middle extending to margin of lobes.
Eyes well rounded, whitish mingled with brown; ocelli dilute brown.
Length of vertex less than half the distance between eyes, and equal to
about one-fourth of the distance across the eyes. Face strong, of a
yellowish color, covered with a dense grayish pubescence; frons distinct
yellow, decidedly convex, traversed by numerous dark yellow arcs; two
black spots near the margin of the vertex, in line with those on the
vertex. Frons three times as long as its width next the clypeus and
twice as long as the latter. Clypeus broad next the frons, strongly
produced at the apex; lorae s.nall, about one-third the width of the
clypeus; genee small, inwardly rounded; rostrum long, the last joint
black. Antennae deeply inserted, basal joint stout. Thorax well devel-
oped, darker in color than the vertex, finely punctate, and pubescent,
twice as broad as long and two and a half times as long as the vertex;
anterior margin angularly rounded, side margins short, rounded inwardly ;
posterior margin concave; scutellum longer than width at base, and half
as long as the pronotum. Venter of thorax yellow except near the
coxae, where it is black. Elytra brownish, pubescent, the outer margins
lighter; venation strong, of typical Philfenus type. Abdomen above
black, the margin somewhat yellow, beneath, brownish black, but pos-
sessing a grayish tinge owing to the pubescence. Legs a light yellowish
brown. Genitalia — ^male last ventral segment a little longer than the
penultimate, .slightly concave on its posterior margin; plates long,
about one and a half times as long as their width at base.

Described from one male.

Habitat: Cape Town. (Mally).

The above species may be distinguished from P. caffer
Stal, by the darker color, the shorter vertex and the elytral
venation.

Genus Poophilus Stal.

Head roundly subangular, disc of vertex flat, vertex nar-
rower than the pronotum, the anterior margin acute; frons
slightly convex; clypeus produced at apex, reaching beyond the
fore coxae. Ocelli almost as far from the eyes as from one
another. Pronotum transverse, sixangled, the lateral margins
short, and the anterior broadly rounded. Scutellum longer
than broad. Elytra densely punctate, apical area narrower and
rounded, the side margins straight as far as the apex.

Poophilus terrenus Walk.

Ptyelus terrenus Walker List Horn. Brit. Mus. III. 709. (1851).
Ptyelus umhrosus Stal Ofv. Vet. Ak. Forh. 97. (1855).
Poophilus umhrosus Stal Hem. Afr. IV. 74. (1866).
Poophilus terrenus Dist. Ins. Transv. IX. 222. (1908).

Color tawny brown. Length 10 mm. Breadth 3.25 mm.

March, 1916] Homopterous Studies. Part I 177

Vertex strong, the anterior margin sharp; length not quite equal to
the width between the eyes; ocelli colorless, closer to one another than
to the eyes. Eyes oval, elongate, brown, prominent; anterior of head
rounded. Face strong, black, interspersed with yellowish spots on the
margin, slightly convex, flat on middle, with numerous transverse fur-
rows; frons with some yellow irregular spots; clypeus yellowish, long,
produced, heart-shaped, about two-thirds of the length of the frons;
rostrum long, black at the tip; loras long, very narrow; cheeks narrow
next the lorae wider beneath the eyes. Pronotum dull brown, the
anterior margin broadly rounded, side margins very acute, posterior
somewhat concave; flat on top, with two small depressions alongside
the median line; length of pronotum greater than the vertex, the breadth
about twice the length. Scutellum much longer than broad, the apex
sharp; venter of thorax black, the pro-, meso-, and metapleura with
yellow borders. Elytra dull brown, with many irregular black mark-
ings, the margins lighter; venation distinct, apex of elytra sharply
rounded. Abdomen yellow beneath, with black for the base. Legs
yellowish with brown spots. Genitalia — female; last ventral segment
not quite as long as the penultimate; pygofers yellow, broad, flattened,
twice as long as their width at base; ovipositor brown, sharp, a little
longer than the pygofers.

Habitat: Transvaal, Pretoria (Swiestra), Lydenburg,
(Krantz), Zoutpansburg (Kaessner), Johannesburg (Fry), Water
val-onder (Ross), Natal, Durban (Mansell Weale), Isipingo
(Marshall), Delagoa Bay (Junod), Kaffraria (Stal), Wynberg,
C. P., (Mally).

SUPERFAMILY JaSSOIDEA.

The members of the Superfamily Jassoidea may be recog-
nized by the character of the tibiae, which are prismatic in shape,
and armed with a row of spines on their posterior margins.

Synopsis of Families.
The following key, taken from Osborn's work on the
Jassoidea of Maine, will illustrate the main characters of the
subfamilies.

A. Elytral nervures forking on the disk.

b. Ocelli located on the disc of the vertex Tettigoniellidae

bb. Ocelli located on border of vertex between vertex and front.. Jassidae
bbb. Ocelli located on front distinctly below border of vertex. . . .

Bythoscopidas

AA. Elytral nervures forking at base and running to apex of elytra, ocelli usually

wanting Typhlocybidae

Besides the works of Walker and Distant, the more
important publications on the South African forms are those
of Melichar, Signoret, Distant and Burmeister.

178 The Ohio Journal of Science [Vol. XVI, No. 5,

FAMILY BYTHOSCOPID^.

The general characters of this family are well marked, the
most conspicuous being the position of the ocelli, which are
located on the front below the vertex. As a rule the vertex
is short and wide, and with the eyes, is generally or often
broader than the pronotum. Definite striations are frequently
observed on the pronotum. The elytral venation is frequently
obscure. The appended synopsis of genera will indicate the
main characters of the genera.

Like the Typhlocybidge, little is known about the South
African representatives of this family. The writer is fortunate
in being able to describe a member from each of four of the most
prominent genera.

Synopsis of Genera.*

A. Antennae inserted in a deep cavity beneath a ledge,
b. Striation of the pronotum transverse.

c. Side margins of the pronotum sharply keeled, of moderate

length Macropsis

bb. Striation of pronotum running obliquely from the middle of its front

margin to the hinder angles Pediopsis

AA. Antennae inserted in a feeble cavity, their base free.

b. Head with the eyes wider than the elytra at the base, meml^rane

with an appendix Idiocerus

bb. Head with the eyes as wide as the elytra at base, no appendix.. Agallia

Genus Macropsis Lew.
Macropsis subolivaceus Stal. (PI. IV, Fig. 1).

Bythoscopus olivascens, Stal. Ofv. Vet. Ak. Forb. I. 99 (1855).

Macropsis subolivaceus, Stal. Hem. Afr. IV. 127. (1866).

Macropsis subolivaceus, Mel. Beit. Z. Kenn. Hom. Deutch Oost-Afrika 297.

(1905).

General color olivaceous. Length, 5 mm. Breadth, 2 mm.
Vertex yellow, very short; well rounded anteriorly and distinctly
striated. Eyes steel gray, small; width between the eyes four times as
long as the vertex. Face short, two-thirds as long as its width across
the eyes; frons yellowish. Clypeus greenish, one and one-half times as
long as its breadth; lorse prominent, not quite as wide as the clypeus.
Ocelli colorless or sanguineous. Pronotum yellowish green, with strong
transverse striations on its posterior half, and smaller striations on the
middle of the anterior half, but not reaching the margin; about three
times as long as the vertex, and about half as long as the width of the
pronotum; anterior margin well rounded, the lateral margins of moderate
length; posterior half broader than the anterior, being the widest part
of the body; convex anteriorly and laterally. Scutcllum a little longer
than broad tapering to a i^oint ; about as long as the pronotum ; olivaceous
in color, but with two large brown spots at the basal angles, and a

*

Adapted from Osborn.

March, 1916] Homopterous Studies. Part I 179

curved depressed line on the middle, behind which are pronounced
transverse striations. Elytra yellowish green, with a fine punctation;
transparent; venation indistinct, some of the veins being indicated by
minute papillce; appendix well developed. Abdomen above yellowish,
beneath greenish. Legs greenish, posterior tibiee very strong. Geni-
talia— female; last ventral seginent more than twice as long as the
preceding, convex, with the posterior margin very slightly concave;
pygofers strong, about three tiines as long as the last ventral seginent,
convex laterally; widely separated on the middle, and narrowing at the
tip; ovipositor equaling the pygofers in length. Male — last ventral
segment about three times as long as the penultimate, strongly pro-
duced to a rounded point pygofers rounded, not as long as the ultimate
ventral segment.

The nymphs of this species are dull, greenish brown in
color, covered with numerous fine hairs or spines, and have a
broadly oval appearance. The vertex is longer than in the
adult, while the pronotum is rectangular. The body is large,
rounded and very hairy.

Habitat: Cape Town (Mally), Rondebosch (Stal), Sierra
Leone (Stal), Tanga (Melichar).

Genus Pediopsis Burm.
Pediopsis capensis sp. n. (PI. IV, Fig. 2).

Form broad and stout, general color greenish yellow,
covered with a fine brown spotting. Propleura with a black
spot. Length 4.5 mm.; width at pronotum 2 mm.

Vertex very short, viewed froin above, narrow at middle, but
becoming slightly wide towards the eyes; greenish in color, with the
brown spots rather obscure. Eyes steel gray, a little wider than the
pronotum, having a flattened oval appearance. Face yellowish green,
broad and of moderate length, with coarse though shallow rugulse and
punctulations ; frontal suture prominent; frons strong, wide between
the eyes; tapering gradually to the clypeus; the latter short, broad, and
prominent, wider next the frons than at apex; lorse long and narrow;
cheeks of moderate width, slightly depressed beneath the eyes; ocelli
colorless. Pronotum olivaceous, with brown spots, prominent; rug«
conspicuous, decidedly oblique; anterior margin broadly triangular,
lateral of moderate length, posterior slightly concave; length about two-
fifths of the breadth; disc convex on posterior half. Scutellum large,
of a yellowish color, with two large, round brown spots located at the
basal angles, about equal to the pronotum in length; a short transverse
line on the posterior half. Venter of thorax yellow, black spots on the
pro- and metapleura. Elytra yellowish, with numerous brown spots; at
apex of the clavus are two brown markings, which when the wings are
at rest, give a distinct spot, difi:erent from the general marking. Vena-
tion distinct, six closed cells on the corium, one basal, two discal, and

ISO The Ohio Journal of Science [Vol. XVI, No. 5,

three anteapical; membrane composed of fine apical cells. Wings very
delicate, membranous, the supernumerary cell absent. Abdomen above
greenish, short, compressed, beneath yellowish. Legs brownish, tarsi
three jointed, the basal joint almost as long as the second and third
combined. Male genitalia; last ventral segment twice as long as the
penultimate; plates as long as the ultimate ventral segment.

Described from two males.

Habitat: Cape Flats, C. P., (Mally).

Genus Idiocerus Lewis.
Idiocerus hewitti. sp. n. (PI. IV, Fig. 3).

Yellowish green, with two black spots on the anterior
margin of the vertex and two spots, also black, on the base of
the scutellum. Length, 5.5 mm. Width across eyes 2.25 mm.

Vertex broad and stout, with the eyes very prominent, greenish in
color; yellow halos around the black spots, which are situated nearer
the eyes than the median line. Eyes very large, brownish black; ocelli
colorless, located nearer the eyes than the middle. Face broad, a little
broader than its length; frons large, convex, yellow with lighter trans-
verse bands on the middle; clypeus a little larger than its breadth; loree
prominent; cheeks somewhat lighter than the rest of the face. Pro-
notum long, with distinct transverse striations. Scutellum yellow, a
little longer than the pronotum, with two round black spots on the base.
Elytra faint yellow, with the venation rather indistinct; apical cells
prominent the sectors set with minute tubercles. Abdomen above
black, beneath greenish yellow; lateral margins green. Legs light yel-
low to whitish. Female genitalia: dull green in color, the last ventral
segment, more than twice as long as the penultimate, notched at the
middle, and slightly concave on its posterior lateral margins; pygofers
large, stout, shorter than the ovipositor, which is broader at the tip,
than at base.

Habitat: Grahamstown, C. P., (Hewitt).

The above species was described from two females sent to
me by Mr. J. Hewitt, Director of the Albany Museum, at
Grahamstown.

Genus Agallia Curtis.
Agallia nigrasterna sp. n. (PI. V, Fig. 1).

Form similar to A. novella Say. Color light yellowish
brown, the elytra whitish. Length of male almost 4 mm.
Breadth 1.25 mm.

Vertex yellow, brownish on the middle, short, about one-fourth of the
length of the pronotum; two large, round, black spots on the anterior
margin; and two faint fuscous bands on the middle, between them;
width of vertex across eyes greater than the pronotum. Face brownish

March, 1916] Homopteroiis Studies. Part I 181

white, the frons brownish on the middle and sides, with a brown band
extending from below the ocelli to the anterior margin of the head;
much wider than the clypeus, which is oval in shape, yellowish, with
the sides marked brown; loree white, not as wide as the clypeus. Cheeks
white, strong and broad. Ocelli colorless. Black markings beneath
the antennal pits. Pronotum strong, brownish on anterior, whitish on
posterior half with two large black spots near the posterior margin;
irregular brown markings in advance of these, and a brown median band.
Pronotum almost twice as wide as its length, the anterior margin
rounded, and the posterior broadly rounded towards the sides; convex
above. Scutellum yellow, with a brownish semi-circular furrow on the
anterior half, not as long as the pronotum; apex tapering to a fine point.
Thorax beneath black. Elytra gray, semi-transparent, the veins dis-
tinct, showing as brown lines. Middle anteapical cell much larger and
longer than the other two; only three apical cells present. Abdomen
above yellow, black at the base, beneath light yellow. Legs light yellow
to whitish. Genitalia: male — last ventral segment a little longer than
the previous ones; valve strong, three times as long as the ultimate
ventral segment, broadly triangular in shape, rounded at apex; plates
triangular, about equalling the valve in length. Pygofers not as long as
the plates, yellowish ventrally, black dorsally.

Described from two males.

Habitat: Cape Town (Mally).

This species may be easily distinguished from A. novella
Say. by the size and shape of the pronotum. In the former
the pronotum is much larger and more convex than in the
latter. Further the black spots on the pronotum of A. novella
are located nearer the middle than in this species.

Agallia cuneata sp. n. (PI. V, Fig. 2).

Form thin and slender with the posterior end of the body
distinctly wedge-shaped. Color light pink, obscured in parts
by a white incrustation ; large round, black spots on vertex and
pronotum. Length 3.5 mm. Breadth scarcely 1 mm.

Vertex small, well rounded, pinkish, the black spots on the anterior
margin surrounded by yellowish halos; length about one-fourth as long
as the pronotum; anterior margin rounded. Eyes yellowish, ocelli black
Face narrow, a little longer than broad; frons whitish, with brown across
the middle, and on the sides to the clypeus; genae almost straight mar-
gined from clypeus to the eyes ; lorse rather long and narrow, not as wide
as the clypeus, which is short and oval, its length about one-fourth of
the frons; sutures marked indistinctly with brown in parts. Pronotum
whitish pink, about one and a half times as broad as its length, and not
as wide as the vertex across the eyes ; convex above both anteriorly and
laterally; anterior margin rounded between the eyes, side margins of

182 The Ohio Journal of Science [Vol. XVI, No. 5,

moderate length; two black spots near the posterior margin, large and
round. Scutellum whitish, about as long as the pronotum. Pro-, meso-
and metapleura black. Elytra covered with a whitish incrustation,
venation distinct, the veins indicated in part by brownish lines; apex of
elytron rather sharply rounded. Four apical cells, and two ante-apicals,
the inner ante-apical being much larger and longer than the other.
Abdomen above blackish gray, the borders and ventral surface yellow.
Legs dirty white. Genitalia : female — last ventral segment about one and
a half times as long as the penultimate, the posterior margin almost
straight, except for a small niche on middle; pygofers about two and a
half times as long as the last ventral segment, and longer than their
width at base; ovipositor longer than pygofers, black at the tip.

Described from one female.

Habitat: Cape Town, C. P. (Mally).

FAMILY TETTIGONID^.

The family Tettigonidas is easily recognized by the position
of the ocelli which are located on the disk of the vertex.

Subfamily Gyponin^ Berg.

Genus Penthimia Germ.
Body oval; head obtuse, the anterior margin rounded.
Pronotum frequently longer than the vertex, sometimes trans-
versely striated. Scutellum a little broader than long.

Penthimia bella Stal.

Penlhimia bella vStal. Hem. Afr. IV. 108. (1866).
Penthimia bella Stal. Ofv. Vet. Ak. Forh. 98. 2. (1855).

General color from above black intermixed with brown and dirty
white, beneath black and brown. Length of female 4.5 mm. Breadth
1.75 mm. Vertex yellowish white with irregular brown markings
arranged along a median Hne; obtusely angular, the length not as great
as the width of the head between the eyes; anterior of head sharply
rounded. Ocelli brown, eyes black. Face black, except the brown
clypeus; sutures distinct; clypeus small, about one-fourth of the length
of the frons. Pronotum a mottled brown, black and white; longer than
the vertex, slightly convex on the anterior half, the lateral margins
rather short. Scutellum yellowish with brown markings at the basal
angles, about two-thirds as long as the pronotum. Elytra whitish but
with a mottled appearance due to the brown and black; a few clear
spaces in the anteai^ical cells, some hyaline areas on the corium, and
middle of costal margin. Abdomen above brownish, lighter ventrally
with the borders yellow. Genitalia : female — pygofers large, yellow with
bluish inarks, convex and very spincy; last ventral segment more than

March, 1916] Homopterous Studies. Part I 183

twice as long as the penuhimate, inwardly rounded on the posterior
margin, and slightly produced on the middle; ovipositor large, longer
than the py gofers.

Habitat: Rondebosch, C. P. (Stal: Mally).

Penthimia vinula Stal. (?)

Penthimia vinula Stal. Hem. Afr. IV. 108. (1866).
Penthimia vinula Stal. Afr. Vet. Ak. Forb. 98. 2. (1855).
Penthimia vinula Distant. Ins. Transi.

Form and appearance of P. bella Stal. Color shiny black mingled in
parts with brown and white. Length 4 mm. Breadth 1.75 mm.
Vertex white but with black markings which are symmetrical along
a median line; length not equal to the width between the eyes; convex
anteriorly, the margin obtuse. Eyes large, chocolate colored, ocelli
black. Face strong, the frons prominent, about three times as long as
the clypeus; lorse about as wide as the clypeus; cheeks large; two large
prominent white spots on the face above the region between the eyes.
Pronotum black with many small white spots; a little longer than the
vertex. Pronotum and vertex transversely striated. Scutellum black
over the major part, with a few white spots at the base, a white spot at
the apex, and two large brown marks on the middle. Elytra fuscous
black; claval area with few white spots; corium with a clear area near
the base of the costal margin, a circular clear space at the apex of the
claval suture and three distinct clear spaces on the area of the ante-
apical cells. Abdomen brownish black above, black on the venter, the
edges of the segments showing as white hnes and the margin a little
lighter than the remainder. Male genitalia : last ventral segment black
on the middle, yellow at the borders, about equal to the penultimate in
length; valve yellowish brown, not as long as the ultimate ventral seg-
ment; plates black, longer than the valve, the tips sharp; pygofer longer
than the plates, black.

Habitat: Cape Town (Mally), Transvaal, Pretoria (Dis-
tant), German East Africa: Amani, Bomole (Melichar).

This species varies from the P. vinula figured by Distant, in
having white on the vertex, pronotum and middle of the
elytral disk.

FAMILY JASSID^.

The true Jassids are characterized by the position of the
ocelli, which are located on the anterior margin of the vertex
where it merges into the frons. The appended synopsis of
tribes, taken from Van Duzee, best illustrates the main
characters.

The family is perhaps better known than any other of the
Jassoid division and the number of described species is far in
excess of the Bythoscopidse and TyphlocybidcC.

184 The Ohio Journal of Science [Vol. XVI, No. 5,

Synopsis of Tribes.

Anterior edge of the head thin and sharp, or more or less foliaceous. . . .Dorydini
Anterior edge of the head sometimes acute, but generally obtuse or rounded,

never thin and foliaceous A.

A. Elytra with two transverse nervures between the first and second sectors

of the corium Deltocephalini

Elytra with but one transverse ncrvure between the first and second

sectors of the corium B.

B. Elytra without a series of anteapical areoles or with but one, formed
by the forking of the outer branch of the first sector; vertex sub-
quadrate, the hind and lateral margins elevated, before feebly
arcuated, with the edge strongly rounded or produced and tumid

before with an obtuse apex Jassini

Elytra with a series of (generally three), apical areoles C.

C. Outer branch of the first sector of the elytra with two forks

evident Athysanini

Outer branch of the first sector of the elytra with its outer fork
obsolete or nearly so, anterior edge of the head well rounded,.
vertex but little, if at all longer on the middle than next the
eye Cicadulini

Tribe Dorydini.

Genus Cephalelus Perch.

Cephalelus— Percheron in Guer. Mag. Zool. ii, Classe IX, (1832).
Dorydium— Burm. Handb. Ent. ii, 1, 106, (1839).

Burm. Gen. Quaedam. Ins^'ct i, (1838).
Cephalelus— Signoret, Ent. vSoc. Fr. 504, 259, (1879).

Kirby, Trans. Ent. Soc. Lond, 412, (1894).

Head long, narrow, very strongly produced; vertex long,
pointed, the sides rounded, more than three times as long as
the width, face large, merging into the vertex; clypeus heart-
shaped. Eyes lateral, elliptical. No ocelli. Antennae short,
the basal joint large and cylindrical, the second long, the third
subcylindric. Pronotum transverse, the lateral margins of
moderate length. Elytra corneous, punctulate, the apices
rounded. Tibiae without spines. Abdomen elongate, the males
much shorter than the females.

Cephalelus infumatus Perch. (PI. VI, Fig. 1).

Cephalelus injiimalus Perch, in Guer, Mag. Zool. ii. Classe IX. pi. 48. (1832).
Dorydium paradoxum Burm. Handb. Ent. ii. 106. (1839).
Cephalelus infumatus Walk. Cat. Hom. Brit. Mus. 637. (1851).
Cephalelus infumatus Amy. & Serv. Essai sur les Jassides. 258. (1878).
Distant Ins. Transv. X. 241. (1910).

General color dark red to brown or yellowish brown in dried spec-
imens. Length of females 11.75 mm. to 12.75 mm. Average length of
twelve females 11.95 mm. Length of males 9.25 to 10.25. Average
length of thirteen males 9.35 mm. Breadth 1.5 mm.

Female — Head dull red to brown above, with an indistinct line along
the middle of the vertex, extending from the anterior margin, to a little
before the eyes; beneath dark red with a broad yellowish band running
along the middle, rather narrow at the anterior, but widening towards
the posterior margin. Vertex about four times as long as its breadth;

March, 1916] Homopterous Studies. Part I 185

with two dull red spots a Httle in advance of the eyes; finely punctate,
and about five times the length of the pronotum. Eyes dark green to
black, rather large. Ocelli absent, but two small depressions are indi-
cated, where one would expect the ocelli. In his original description
Percheron noted the presence of ocelli, but later Burmeister drew atten-
tion to the fact that these were mere depressions. Antennae short,
sharp at the distal end, inserted in deep pits. Facial sutures distinct;
genae yellowish, rounded; clypeus large, a little longer than broad, taper-
ing gradually to the rostrum. Pronotum red, darker at the sides; a
longitudinal line along the middle. Scutellum shorter than the prono-
tum. Elytra dark red, broadly oval in shape, densely punctulate, the
punctation arranged in definite series; shorter than the abdomen.
Abdomen above red, beneath light brown to yellowish. Genitalia: last
ventral segment small and distinctly notched and grooved on the mid-
dle, not as long as the penultimate; pygofers long and narrow, widely
separated at the base, becoming closer on the middle, and separating
again at the tip. Ovipositor long, thin, much longer than the pygofers,
its length about 3.5 mm. Legs light brown, the femurs stout.

Male — Face with a distinct yellow band along the middle; elytra
much longer than the abdomen, light brown along the margin of the
corium. Genitalia, last ventral segment not quite as long as the
penultimate, valve about as long as the last ventral segment, triangular
in shape; plates long, rounded at the tips, about twice as long as the
valve; pygofers a little shorter than the plates.

This interesting insect is one of the most unique in Southern Africa.
According to the literature it seems to be scarce in collections, but in the
material on hand it is quite abundant. The original description was
based on a single specimen, the habitat of which was unknown until
later it was identified with the Cape. Burmeister stated that he had
only seen two specimens, one at Berlin and the other at Hamburg, and
he mentions the habitat as the Cape of Good Hope. As far as the
writer is aware, this is the onh^ complete description of both male and
female that has been published.

x\n interesting case of protective mimicry is recorded for Cephalelus
infumatus, and this probably accounts for its scarcity in collections.
According to Professor Osborn, "The protective feature comes in from
the fact that the aborted leaf -sheaths on the stem of the plant form sharp
spines occurring at intervals along the length of the stem, and these are
perfectly reproduced in the form and color of the insect. So close is the
resemblance that when a number of the spines are mounted separately
alongside of the insects, it is very difficult to distinguish them without
the most careful scrutiny. When the specimens were first received, I
had looked them over some time before noticing that a number were not
insects at all, but simply spurs and had there not been one mounted
with a fragment of stem along with an insect beside it, I might have
taken a much longer time to make the discovery. I have shown the set
to a number of individuals, who have taken quite a little time to make
the same discovery. "

"According to Mr. Mally the insect lives on the rush Dovea tec-
torum Masters, the spurs of which are mimicked. I may mention that
the stems are green, while the aborted leaf -sheaths are dark brown. "

186 The Ohio Journal of Science [Vol. XVI, No. 5,

Tribe Deltocephalini.

Genus Deltocephalus Bumi.

Body oblong or oval, elongate; head with the eyes as wide
as the pronotum, pointed in front; ocelli on margin between
vertex and front. Vertex flat or slightly convex at the lateral
margins, more or less angularly produced in front. Inner
sector of elytra forked twice, three anteapical cells present.
In the Brachypterous forms there is a decided reduction in the
number of veins.

Deltocephalus breviatus sp. n. (PI. VI, Fig. 2).

General color yellowish green, Brachypterous form. Length

2.75 mm. Breadth scarcely 1 mm.

Male — Vertex yellow, with a median line extending from the
posterior margin to a little beyond the middle ; length a little more than
twice the width between the eyes; anterior margin sharply pointed,
acutely rounded; eyes greenish white, large, prominent, extending
backward beyond the anterior edge of the pronotum. Ocelli small,
colorless, located near the eyes. Face yellow, the frons traversed by
six to eight brown arcs; length of entire face about equal to the width
across the eyes; frons more than twice as long as its width next clypeus,
and more than twice as long as the clypeus, which is one and one-half
times as long as it is broad and is parallel margined. Loras prominent,
cheeks broad and strong. Pronotum greenish-yellow above, black
beneath; broad, not as long as the vertex, the anterior margin rounded
between the eyes. Scutellum small, yellowish green, half as long as the
pronotum. Elytra yellowish, transparent, short, extending to the
penultimate dorsal segment of the abdomen; venation rather indistinct,
apices of elytra broadly rounded. Abdomen above yellowish, the first
two segments black on their lateral margins; beneath black, with
yellow borders. Legs light yellowish, the coxa; black. Genitalia;
last ventral segment very small, less than half as long as the penultimate;
rounded broadly on its posterior margin, black on the anterior, and light
yellow on the posterior; valve black, inore than twice as long as the last
ventral segment, rounded at its apex; plates long triangular, yellow,
with occasional black spots, tips rounded. Pygofers large, longer
than the ]jlates, very spiny, the spines forming a crown at the tip;
ventral color black at base, yellow at the tip ; dorsal yellow, but black at
the bases of the lateral margins and the tip black.

Female — General color the same as the male. Head soinewhat
sharper and more pointed. Genital apparatus, last ventral segment
black, a little larger than the penultimate, sinuate on the middle, the
posterior margins curving slightly to the sides; pygofers yellowish,
more or less colored with brown and black, widely separated at the base,
but converging towards the tip; the amount of brown coloration of the
pygofers varies but as a rule is confined to the basal half; ovipositor

March, 1916] Homopteroiis Studies. Part I. 187

black, strong, equaling the pygofers in length; ventral tip of pygofers
black, the spines strong, forming the crown as in the male.

Described from three females and seven males.
Habitat: Cape Town, C. P. (Mally).

Deltocephalus aristida sp. n. (PI. VI, Fig. 3).

General color brownish black. Form long and slender.

Length of female 4 mm. Breadth scarcely 1 mm.

Head brownish black, prominent; disc of vertex flat, slightly rounded
towards the sides, the apex very pointed; a median hne extending from
the posterior margin to the tip of vertex; length greater than the width
and equal to about half the width across the eyes. Face strong, longer
than its width; frons black with faint yellowish arcs, three times as
long as its width next to clypeus, and two and one-half times as long as
the latter; clypeus black, with a faint yellowish tinge, one and a half
times as long as its width next to the frons, sides almost parallel, apex
rounded; lorte prominent, half as wide as the clypeus; genae well rounded,
depressed beneath the eyes, black with a narrow yellow border. Point
of insertion of the antennae deep. Face, vertex, prothorax and scutellum
finely punctulate. Pronotum well rounded between the eyes, black
with five indistinct yellowish longitudinal lines, one on the middle and
two on either side, near the lateral margins; posterior margin slightly
concave, lateral margins somewhat convex, short; length of pronotum
not quite as long as the vertex; sides and venter black with a bluish
tinge. Scutellurn black, about equal to the pronotum in length.
Elytra brownish, becoming lighter at the apex of the corium; veins
showing as lighter lines; appendix strong; abdomen above blackish
brown, beneath black; legs lighter in color than the rest of the body.
Genitalia, Female — ultimate ventral segment about twice as long as
the previous, strongly produced on the middle, the posterior margin
rounded, inwardly, the apex somewhat convex; pygofers strong, widely
separated at the base, and closer near the tip, three times as long as
the last ventral segment; color brown with a yellowish tinge; ovipositor
wide, a little longer than the pygofer.

Described from one female.

Habitat: Cape Town, C. P. (Mally).

Tribe Athysanini.
Genus Athysanus Burm.
Body robust, somewhat rounded at the sides. Head with
eyes generally wider than the pronotum, obtuse in front.
Vertex slightly produced; ocelli located near the eyes on the
margin between vertex and front. Pronotum short, trans-
verse, sometimes striated. El^'tra with inner sector forked
twice, three anteapical cells and frequently five apicals.
Ovipositor short, little if any longer than the pygofer.

188 The Ohio Journal of Science [Vol. XVI, No. 5,

Athysanus capicola vStal. (PL VII, Fig. 1).

rhainnotettix capicola Stal Hem. Afr. IV. 123. (1866).
Athysanus capicola vStal. Ofv. Vet. Ak. Forh. 99. 2. (1S55).

General color yellowish or dirty white. Length of male
5 mm., female 5.5 mm. Breadth 1.75 mm.

Vertex rather short, not produced, whitish in color with a strong
black or brown transverse band across the middle ; prominent and run-
ning from eye to eye ; length of vertex about equal to one-half tiines the
width between the eyes; anterior margin of the head obtusely rounded,
the lateral margins sloping, slightly convex on disc with rather indis-
tinct striations. Eyes dull green, large. Ocelli located nearer the
eyes than to the middle, dilute red. Face strong, yellowish, with many
dark yellow transverse arcs on the frons; frons a little longer than its
breadth, much wider than the clypeus, and about two and a half times
as long. Cheeks and lorse lighter in color than the frons, the latter as
wide as the clypeus; clypeus produced, twice as long as its width, the
sides subparallel and the apex rounded; rostrum rather long. Pro-
notum dilute yellow with numerous small brown spots; an irregular row
of brownish spots on the anterior half arranged transversel}'' ; length of
pronotum greater than that of the vertex; width more than twice the
length. Scutellum yellow, not quite as long as the pronotum, trans-
versely striated at the apex. Elytra equaling the body in length,
overlapping at the tips; color yellow, the veins showing as brown lines.
Appendix strong. Abdomen above yellow, with small black spots on
the lateral margins of each segment; beneath yellowish in females,
brownish in males. Legs light yellow to whitish. Genitalia female:
last ventral segment more than twice as long as the penultimate,
notched at the middle, convex on the surface; pygofers long and slender,
about two and a half times as long as their width at base, and three
times as long as the last ventral segment ; ovipositor strong, longer than
the pygofers, sharp at the tip. Male: last ventral segment, a little
longer than the previous one, brownish black in color; valve a little
longer than the last ventral segtnent, plates narrow somewhat rounded
at the tip, about twice as long as the valve; pygofers not quite as long
as the plates.

This jassid is by far one of the most common in Southern
Africa and has been taken in great numbers on grasses and
forage crops in the Eastern Province of Cape Colony. It is
undoubtedly of some economic importance, not only on account
of its numbers, but on account of its wide distribution through-
out the provinces. It exists under a variety of different
conditions, ranging from tropical, through subtropical to
temperate regions, judging from the fact that it has been
taken commonly in German East Africa, the Island of Mauri-
tius, Senegal, Natal and the southernmost portions of the Cape.

March, 1916] Homopterous Studies. Part I 189

It is closely related to Athysanus exitiosus, a form which
is most common and of great economic importance in the
United States. Morphologically the two agree in many
characters, and show similar variations. The North American
form is undoubtedly a tropical one, which has gradually
migrated from Central America to the north, its food habits
changing with time and the propagation of cereal crops.
Similarly the African form is probably of tropical ancestry,
and has gradually spread from the equator southward till it
reached the coastal region. The cases are parallel in point and
are of interest on that account. While it may seem a far
stretch of imagination to consider a common ancestry for the
two species, yet such a conjecture would seem feasible, in view
of the land connection which once existed between Africa and
South America.

Habitat: Rondebosch, C. P. (Stal), Cape Town (Mally),
Grahamstown (Cogan), De Aar, C. P. (Cogan), Mauritius
(Stal), German East Africa, Amani, Sigital, Tanga, Bomole,
Kiboteni (Melichar).

Athysanus aethiopica sp. n. (PI. VII, Fig. 2).

General color greenish white, with a varying amount of
brown or black on the face. Length 3. mm. Breadth about
1 mm.

Female: Vertex whitish with an irregular black marking at the
apex, not quite as long as the width between the eyes; ocelli colorless,
eyes greenish. Face yellow, but prominently marked with black; frons
yellowish white, except for the strong black arcs, about twice its length
next the clypeus; loras yellow with the sutures brown to black; cheeks
yellowish green; clypeus one and a half times as long as its width next
the frons, yellow with brown on the middle; rostrum brownish black.
Pronotum greenish, broadly rounded between the eyes, a little shorter
than the vertex, faintly transversely striated; scutellum yellowish, not
quite as long as the pronotum. Sternum black. Elytra a little longer
than the abdomen, semi-transparent, light greenish white in color.
Abdomen above black with the borders yellow, beneath yellow but
with black for the base and the middle. Genitalia : last ventral segment
whitish, more than twice as long as the penultimate; posterior margin
slightly curved inward and produced on the middle; pygofers long and
slender, two and a half times as long as their width at base; ovipositor
brown at the tip, a little longer than the pygofers; ovipositor brown at
tip, a little longer than the pygofers.

Male: General color the same as female; the brown coloration is
perhaps more prominent on the males. Black marking on the vertex
not as evident. Abdomen entirelv black on dorsal and ventral sur-

190 The Ohio Journal of Science [Vol. XVI, No. 5,

faces. Genitalia: last ventral segment black on middle, yellow at the
sides; little longer than the penultimate; valve black at base, yellow on
border, scarcely visible; plates whitish long, somewhat romided at the
tips; pygofer a little longer than the plates. Legs light yellowish white.

Described from four males and four females.

Habitat: Cape Town (Mally).

The species described above is subject to some variation
in the distribution of the brown coloration of the face, vertex
and abdomen. In some, the black marking on the vertex is
absent, in others very prominent; in others the black on the
face extends all over except for the middle of the frons and
cheeks and loras, while it may be wanting in some other
specimens.

Athysanus eriocephalus sp. n. (PI. VII, Fig. 3).

General color light yellowish to brownish. Length 4 mm.
Breadth 1.5 mm.

Female — Color yellowish brown, with the vertex a dirty white,
marked with irregularly shaped brown markings. Head strong, the
vertex somewhat produced, with the anterior margin rather sharp,
and the apex angular; length of vertex a third greater than the pronotum,
and less than the width between the eyes, equalling about two-fifths
of the total width across the eyes. Eyes black, prominent; ocelli
located near the eyes. Face strong, the frons marked by numerous
transverse brown arcs, about one and a half times as long as its width
a little above the clypeus; the latter about one and a half times as
long as its breadth, the margins subparallel; frons about two and a half
times as long as the clypeus; lorae not quite as wide as the clypeus.
Pronotum a dirty white with brownish markings, narrow, about three
times as wide as its length, the anterior margin broadly rounded, the
lateral margins short. Scutellum not quite as long as the pronotum.
Elytra yellowish white, with occasional brownish spots, veins showing
as brown lines; brown spots on the middle anteapical cell, the first
discal cell, and two on the second discal cell; margins well rounded.
Abdomen above brownish black, beneath brownish yellow. Genitalia,
last ventral segment about one and a half times as long as the penulti-
mate; posterior margin deeply emarginate, color yellow, the pygofers
brownish, much wider at the base than the tip. Ovipositor blackish,
strong, a little longer than the pygofers.

Male — Lighter than the female, in fact a light straw color; elytra
lighter, otherwise resembling the female. Genitalia: Last ventral
segment brown on the middle, whitish yellow at the sides, almost
one and a half times as long as the penultimate; valve small, semi-
circular, scarcely visible; plates yellowish brown, almost as long as last
ventral segment; pygofer a little longer than the plates.

Described from two females and five males.
Habitat: Cape Town (Mally).

March, 1916] Homopterous Studies. Part I 191

Athysanus cyclopia sp. n. (PI. VII, Fig. 4).

General color dull brownish, with the elytra bluish gray;

form short and broad. Length 3 mm. Breadth 1.25 mm.

Vertex brown, flat on the disk, the apex pointed and the margins
sloping; small brown lines fringing the anterior margin running from
the apex to the eyes; these arcs are continued over on the face. A
small median line running from the middle of the posterior margin
to the middle of the disk; length not equal to the width between the
eyes, and about one-third of the width across the eyes. Ocelli colorless;
eyes brown. Face yellowish brown, with brown arcs on the frons;
rostrum dark brown. Frons large, rather swollen near the vertex;
clypeus one and a half times as long as its breadth; lorae almost as wide
as the clypeus. Pronotum grayish brown, with indistinct brown marks
behind the eyes, about two-thirds of the length of the vertex; anterior
margin broadly rounded; lateral margins very short; scutellum with
two faint black marks on the middle, about two-thirds of the length of
the pronotum; sternum and metapleura whitish yellow. Elytra with
fuscous marks on the middle of the claval area; small black spot at
apex of claval suture; corium with brownish marks on the middle, the
anteapical cells marked with brown, and the costal margin before the
apical cell black; elytra not as long as the abdomen; venation reduced.
Abdomen above brownish yellow, beneath yellowish with brown for
the middle and base. Female genitalia: Last ventral segment one and a
half times as long as the penultimate, the posterior margin deeply
concave ; middle of posterior margin brown ; pygofers three times as long
as the last ventral segment, widely separated on the middle and con-
verging to the tip of the ovipositor, not as long as the ovipositor; the
latter strong, brown with sides black. Legs dull yellowish with the
spines brown.

Described from one female.
Habitat: Cape Town (Mally).

Athysanus nemesia sp. n. (PI. VIII, Fig. 1).

Brachypterous form. Color yellowish, faded. Length,

3.5 mm. Breadth 1.25 mm.

Vertex light yellow, flat on disc, sloping at sides; width between
the eyes a little longer than the length of the vertex, anterior margin
angularly rounded; eyes grayish, large, prominent; frons much wider
than the clypeus and about two and a half times as long, whitish in
color and traversed by numerous yellowish brown arcs; clypeus rather
long, twice as long as its breadth, angular at apex; lorce narrower than
the clypeus. Point of insertion of the antenna surrounded by a
brownish marking. Pronotum more than twice as broad as long, and
shorter than the vertex, yellowish in color, lighter on the anterior half,
the posterior half distinctly transversely striated; anterior margin
broadly rounded, the lateral margins short; scutellum equalling the
pronotum in length. Sternum yellow, dorsal surface lighter. Elytra
with the venation distinct, but reduced, much shorter than the abdomen.

192 The Ohio Journal of Science [Vol. XVI, No. 5,

Genitalia: Male — last ventral seginent not quite as lon<:^ as the penulti-
mate; plates roundly triangular, a little more than twice as long as the
last ventral segment, and longer than the pygofers. Legs a dirty
white.

Described from one male.

Habitat: Cape Town (Mally).

Genus Thamnotettix Zett.

Body oblong or oval, widest in the middle. Pronotum
strongly curved in front, the side margins short. Head usually
short. Scutellum generally as long or not quite as long as the
pronotum. Elytra longer than the abdomen and overlapping
at the apex.

This genus is well represented in South Africa, Stal having
described a number of forms from the region of the Cape.

Thamnotettix karrooensis sp. n. (PI. VIII, Fig. 2).

General color brownish white. Length 3.5 mm. Breadth

1.25 mm.

Vertex white, with a dilute brown pattern, angularly rounded, the
length equalling the width between the eyes, and about one-third of the
distance across the eyes. Eyes large, dark brown, ocelli dark brown,
surrounded by clear white spaces. Face dull brown, the frons two and
a half times as long as the clypeus, and twice as long as its width between
the antennae; clypeus narrow, its sides almost parrallel, twice as long
as its width next the frons; lora; about equalling the clypeus in width.
Pronotum well rounded on its anterior margin, dirty brown in color,
with an irregular pattern, one and a third times as long as the vertex;
sternum yellow; black spots on the pro-, meso- and metapleura.
Scutellum almost as long as the pronotum, with brown markings on the
middle and at the basal angles. Elytra a dull white, the veins distinctly
marked with fuscous, the outer margin of the corium white, except for
the minute brown spots. Abdomen dorsally black, with yellow margins,
ventrally dirty white, with black on the base and the middle. Genitalia :
Female — Last ventral segment two and a half times as long as the
preceding, the posterior margin inwardly rounded and slightly produced
on the middle; pygofer one and a half times as long as the width at
base, and three times as long as the last ventral segment; ovipositor a
little longer than the pygofers. Male: Valve brown, with a ^^cllow
border, last ventral segment equalling the penultimate in length, but
not quite as long as the valve ; plates long and narrow.

Described from numerous examples of males and females
from Beaufort West, C. P. (Mally).

Thamnotettix karrooensis var. pallidus.

Form and shape the same as T. karroensis. General color light
yellowish to whitish, with the brown coloration generally absent. Face
light vcllow, the frons marked with dilute brown arcs. Ocelli san-

March, 1916] Ilomopterous Studies. Part I 193

guineous. Genitalia female : last ventral segment almost two and a half
times as long as the penultimate, white with brownish markings on the
anterior half. Male: last ventral segment a little longer than the pre-
ceding. Males distinctly brow^n on the middle of the ventral part of
the abdomen, the lateral margins yellow.

This variety was described from nine females and three
males which were separated from T. karrooensis, on account
of the absence of brown color pattern, and the general pre-
dominance of yellow.

Habitat: Beaufort West, C. P. (Mally).

Thamnotettix cotula sp. n. (PI. VIII, Fig. 3).

General color yellowish brown. Length 3.5 mm. Breadth
1.25 mm.

Female: Head with the eyes prominent, vertex almost as long as the
pronotum, fuscous yellow in color and characteristically marked with
ten brown to black spots — -two situated on the middle, one on either
side of the median line, two somewhat smaller alongside these, but
nearer the eyes, two large angular spots near the anterior margin,
located close to one another and to the median line, two smaller spots on
the anterior margin in advance of these ; the other two spots are on the
anterior half close to the lateral margin. The arrangement of these
spots gives the insect a very characteristic appearance. Vertex acutely
angled. Face strong, the frons fuscous with light arcs; clypeus almost
twice as long as its width, less than half as long as the frons. Eyes
large, dark steel gray; ocelli colorless located very close to the eyes.
Pronotum fuscous yellow, equalling or a little longer than the vertex.
Scutellum shorter than the pronotum, of the same yellow brown color.
Elytra yellowish, transparent, the claval area irregularly marked with
fuscous; apical cells fuscous at their borders. Abdomen above black,
with yellow borders, beneath yellow. Legs light yellowish wdth alter-
nate bands of fuscous on the coxag and femora. Genital apparatus:
ultimate ventral segment somewhat narrow, a little longer than the
previous one, posterior margin notched at the middle, and rounding
slightly to the sides; pygofers dark colored, twice as long as their wddth
at base ; spines strong and stout fonning a rough crown at the tip of the
ovipositor; the latter is longer than the pygofer, and is black at the
sides and tip.

Male: General color the same as for the female; vertex shorter; the
fuscous markings on the apical cells absent or not as prominent.
Abdomen beneath dark brown. Genitalia: last ventral segment yellow
on the middle, black at the sides, equalling the penultimate in length;
valve semi-circular, small, not well exposed; plates angular at the tips,
one and a half times as long as the last ventral segment; pygofers longer
than the plates, rounded laterally; spines large.

Described from one male and one female.
Habitat: Cape Town (Mally).

194 The Ohio Journal of Science [Vol. XVI, No. 5,

Thamnotettix pentzia sp. n. (PI. IX, Fig. 1).

General color brownish, somewhat smoky. Length of

female 4.5 mm; male 4 mm. Breadth 1.35 mm.

Vertex about half the length of the pronotum; disk flat and sloping,
width between the eyes greater than the length on the middle, color
whitish marked irregularly with fuscous. Eyes large, dull reddish,
extending back almost to the middle of the lateral margin of the prono-
tum; ocelli red, located near the eyes. Color of face, a dirty white with
indistinct brown arcs on the frons, the lora^ brownish next the clypeus;
width of frons at the eyes shorter than the length; clypeus a third of the
length of the frons, rectangular in shape, its length being twice that of
its breadth; loras as wide as the clypeus. Antennas long, inserted
deeply, the point of insertion being brownish. Pronotum twice as wide
as its length, color bluish white with many transverse markings of a
brown color and a distinct pattern; lateral margins yellowish, below
black. Scutellum not quite as long as the pronotum, wider than long;
with two prominently brown spots alongside the middle, and two yel-
lowish markings at the basal angles, otherwise dirty white. Elytra
white with the brownish pattern, very long, the appendix narrow, the
margins transparent and without brown markings on the corium as far
as the apical cells. Abdomen above black, whitish on the lateral mar-
gins, and black beneath. GenitaHa female: last ventral segment almost
three times as long as the penultimate, and about one and a half times
as wide as its length, roundedly produced and notched on the middle;
penultimate segment slightly curved inward on the middle of its posterior
margin; pygofers two and a half times as long as the last ventral seg-
ment, and one and two-thirds longer than the width at base; ovipositor
broad, light colored, except at the tip which is black, longer than the
pygofer. Male: Whitish in color, the last ventral segment a little
longer than the penultimate, valve small about one-third as long as the
last ventral segment ; plates sharp and long, about two and a half times
the length of the ultimate ventral segment.

The males of this species are much lighter in color ventrally
than the females.

Described from two females and one male.

Thamnotettix struthiola sp. n. (PI. IX, Fig. 2).

General color bluish white with a brownish black pattern.

Length 3.75 mm. Breadth 1.25 mm.

Vertex white with delicate though distinct black markings; a short
median line extending from the posterior margin to the middle; width
Ijctwcen the eyes about equal to twice the length of the vertex, which is
flat on the disk, angularly rounded at the apex, and has its sides slo]jing;
width across the eyes almost three times the length of the vertex. Eyes
large, well rounded, dark gray in color; ocelli dilute red, located near
the extremities of the frontal sutures. Face white intcrsj^erscd with
brown and black markings, which arc somewhat variable in the different

March, 1916] Homopterous Studies. Part I 195

individuals; frons with two brown markings near the margin of the
vertex and from four to six brownish arcs on the middle, length five
times as much as the width next the clypeus and two and a half times as
long as the latter, which is strong, well rounded at the tip, where it is a
little wider than at the base; clypeus about twice as long as its width;
lorffi not quite as wide as the clypeus, gense white, broad. Brown spots
on the face between the frontal sutures and the eyes, just beneath the
insertion of the antennas. Pronotum irregularly marked transversely
with wavy brown; almost twice as long as the vertex, flat on the middle
but slightly convex at the sides; lateral margins short; width of pro-
notum equal to twice its length; sternum jet black. Scutellum dirty
brown with two blackish markings at the basal angles, a rectangular
brown marking on the middle and extending to the apex; indistinct
brown spots on the middle and anterior half; length about equaling that
of the pronotum. Elytra whitish blue, with a distinct brown pattern;
claval area rather long, leaving a small apical area ; outer borders white
or with few brown marks. Genitalia male: Last ventral segment
brownish, a little longer than the penultimate; valve almost as long as
the ultimate segment, plates long, slender and sharp, much longer than
the pygofers and about three times as long as the last ventral segment;
tips very pointed. Female: Last ventral segment whitish, about four
times as long as the preceding ; posterior margin inwardly and angularly
rounded, then produced on the middle, the production being pronounced;
slightly convex on the top; pygofers brownish, strong, almost three
times as long as the last ventral segment and more than twice as long
as their width at base; rather widely separated; ovipositor long and
broad, longer than the pygofers, sharp at the tip.

Described from three females and four males.
Habitat: Beaufort West, C. P. (Mally).

Tribe Cicadulini.

Genus Cicadula Zett.
Body elongate or oblong, usually much narrowed behind.
Head obtuse in front; frons almost straight sided. Pronotum
usually longer than the vertex. Elytra longer than the abdo-
men, overlapping at the apex; appendix present; inner sector
not forked.

Cicadula 6-notata Fall.

Cicadula sexnotata Fallen. Acta Holm. XXII. 34. (1806).

Edwards. Hem. Homop. Brit. Is. 187. (1896).
Melichar, Cicad. v. Mittel-Europa. 309. (1896).
Osborn. Bull. U. S. Dept. Agr. No. 108. 97. (1912).

General color light yellowish green. Length 3.5 to 4 mm.

Vertex marked characteristically with six black spots arranged in
pairs, two on the anterior margin near the middle, two larger posterior
to these, and two smaller spots on the hind part of the vertex. Frons
prominently marked with black lines. Body black above, yellow
below; abdomen black with the lateral ventral borders yellow. Genitalia:

196 The Ohio Journal of Science [Vol. XVI, No. 5,

Last ventral segment of female yellow, a little longer than the penulti-
mate; pygofer yellow, ovipositor black, equalling the pygofer in length.
Male: Color whitish, valve short, somewhat angular; pygofer longer
than the plates, which are triangular.

This insect is here recorded from South Africa for the first
time. It is widely distributed over Europe and North America,
having attracted considerable attention on those two continents
because of its economic importance. Osborn places it among
the six most important leafhoppers affecting cereal and forage
crops in the United States. Its occurrence in South Africa is
interesting, in view of the attention which it has attracted in
other countries.

Habitat: Cape Town (Mally).

Cicadula longiforma sp. n. (PI. XI, Fig. 3).

Form long and slender, resembling a Gnathodus to some

extent. General color light yellow. Length of female 4.25

to 4.5 mm. ; male 4 mm. Breadth 1 mm.

Vertex yellow, narrow, rounded anteriorly; two light brownish arcs
on the anterior margin, a small longitudinal line on the iniddle, extending
from the posterior margin; length about one-third of the width between
the eyes. Face generally yellowish brown, with the cheeks lighter in
color; frons twice as long as its width, and three times the length of
the clypeus, with six arcs traversing its surface; cheeks rather broad,
equalling the frons in width ; clypeus about one and a half times as long
as its width and about as wide as the lora. Eyes large and prominent,
black below and grayish above; ocelli dilute brown, located close to the
eyes. Thorax well developed, the pronotum three times as long as the
vertex; slightly convex on the middle; color light yellow with many
irregular and indistinct brown markings on the anterior half; anterior
margin well rounded between the eyes, the posterior straight. Scutellum
yellowish, with a few irregular faint brown spots, basal angles of a
deeper hue than the apex, more than half as long as the pronotum, with
a distinct transverse line on the middle. Elytra long, much longer
than the abdomen, faint yellow, transparent; length exceeding the
abdomen by the distance from the apex of the claval suture to the
apex of the membrane. Abdoinen above brownish, yellow at the
lateral margins; beneath yellow, interspersed with black. Legs light
yellow with the tarsi brown. Genitalia: Female — -last ventral segment
longer than the penultimate, emarginate, convex; pygofers long and
narrow, widely separated at the base, about twice as long as the last
ventral seginent and about one and a half times as long as the width at
base; ovipositor equalling the pygofers in length, rounded at the tip.
Male: Last ventral segment large, longer than the preceding; valve
thick, shorter than the last ventral segment; plates long and narrow at
the tips; pygofers longer than the plates.

Described from two males and two females.
Habitat: Cape Town, C. P. (Mally).

March, 1916] Homopteroits Studies. Part I 197

FAMILY TYPHLOCYBID.E.

The members of this family may be easily recognized by the
four longitudinal veins or sectors of the elytra, which fork at the
base and run to the cross-nervures, forming the apical cells.
There are no anteapical cells in the elytra, nor is there a super-
numerary cell present in the hind wings.

Genus Empoasca Walsh.
Generally small species, with the sectors of the posterior
wings ending in a marginal vein, and with one apical cell in the
hind wing. No appendix present on the elytron.

Empoasca protea sp. n. (PI. X, Fig. 1).

Color greenish yellow, with the green predominating.

Length 2 mm. Breadth .5 mm.

Face light yellow, fainter next the clypeus; gen«, lorse and clypeus
light green. Entire length of face exceeding the breadth by about
one-half of the former. Head somewhat large, slightly wider than the
pronotmn; vertex greenish, with irregular dark markings, and a faint
white line extending along the middle from the posterior to the anterior
margin; slightly elevated, giving a convex appearance. Anterior of
head angularly rounded, the angle less than a right angle. Eyes dark
green to black, large; width between eyes a little more than the length
of the vertex. Pronotum brownish green, with a faint white line on the
middle, running longitudinally from the posterior margin almost to the
anterior edge; two rather indistinct spots on either side of this line,
located on the anterior half; length of pronotum a little greater than the
vertex; anterior margin almost straight between the eyes, lateral
margins rounded, slightly convex above; twice as wide as its length.
Scutellum greenish brown, about equalling the pronotum in length; a
small transverse furrow near the apex. Elytra light green, translucent;
venation distinct. Hind wings with the marginal vein somewhat
produced. Abdomen yellowish, below greenish. Legs green, yellow
at coxse. Female genitalia: distinct green, last ventral segment
twice as long as the penultimate, sinuate and roundedly produced on
middle. Pygofers strong, twice as long as the width at base, ovipositor
a little longer.

Described from three females.

Habitat: Table Mountain, Cape Town (Mally).

Empoasca heliophila sp. n. (PI. X, Fig. 2).

Color yellowish, more or less tinged with green. Form long

and slender. Length 3 mm. Breadth scarcely 1 mm.

Face distinctly yellow, shading into greenish below, long and slender,
with the clypeus about one-third of the length of the frons. Cheeks
and lorffi greenish yellow; eyes pale green. Ocelli present, located on the
anterior margin of the head, brown in color. Vertex yellow, slightly
produced in front, its length less than the breadth between the eyes, and

198 The Ohio Jotinml of Science [Vol. XVI, No. 5,

equal to about half the length of the pronotum and about one-third of
the total width of the head across the eyes. Pronotum yellow, lighter
than the head on its posterior half; not quite as long as the width
between eyes. Scutelluni light brown to yellow, not quite as long as the
pronotum. Elytra pale greenish yellow. Abdomen dorsally yellowish
green, venter greenish. Legs light yellowish green. Female genitalia:
Last ventral segment more than twice as long as the penultimate,
produced on middle, rounding to the sides; pygofers twice as long as
their width at base. Ovipositor longer than the pygofers.

Described from three females.
Habitat: Cape Town (Mally),

Genus Typhlocyba Germ.

Sectors of the posterior wings ending in the wing margin, no
marginal vein. Only three veins running to the margin.

Typhlocyba purpureatincta sp. n. (PI. X, Fig. 3).

Color dark brown above, tinged with purple, beneath

yellowish. Length almost 3.25 mm. Breadth 1 mm.

Face brownish yellow, the clypeus darker, almost black, with the
cheeks and \orse light yellow. Eyes black above, yellow below. Vertex
faint yellow, with two irregular dark spots near the middle, moderately
produced, the apex considerably rounded; anterior margin angularly
rounded, the angle less than a right angle; length of vertex about equal
to half the width between the eyes. Pronotum brown above, yellow
beneath, anterior margin well rounded between the eyes; posterior half
wider than the head; almost twice as broad as its length and about
twice as long as the vertex; posterior margin slightly concave; two fur-
rows running from the middle behind the eyes, to a little beyond the
posterior half. Scutcllum brownish at angles next the pronotum, with
a rectangular purplish marking on the middle; indistinctly striate; a
httle longer than the pronotum. Elytra light brown, with a distinct
purple tinge, translucent, the veins showing as darker brown lines; a
pronounced longitudinal ]j)ur]jle marking on the outer margin of the
middle of the corium; entire margin of elytron of a darker hue than the
remainder; two apical cells apparent in posterior wing. Abdomen
yellowish brown dorsally, dirty yellow ventrally. Legs a dirty }'ellow,
hind tibiae hinged with purple. Female genitalia: dark purple, the
last ventral segment brownish, a little longer than the penultimate;
ovipositor narrow, a little longer than the pygofers.

Described from two females.

Habitat: Table Mountain, Cape Town (Mally).

Typhlocyba mallyi sp. n. (PI. XI, Fig. 1).

General color yellowish brown, with the elytra dull greenish.

Form short and stout. Length not quite 3 mm. Breadth a

little more than 1 mm.

Vertex yellowish brown, unicolorous with the face, not produced at
all ; considerably rounded anteriorly, and slightly elevated at the middle;

March, 1916] Homopteroiis Studies. Part I 199

about half as long as the pronotum; a small black line extending from
the posterior margin to the middle; width between the eyes about three
times the length of vertex. Face yellowish brown with the frontal
sutures almost black; frons narrow, three times as long as its width;
clypeus dark brown, about one-fourth of the length of the frons; lorag
small, light yellow; cheeks somewhat fainter in color. Ocelli present,
colorless, located at the extremities of the frontal sutures. Pronotum
yellow on anterior half, brown on posterior. More than twice as broad
as long, the length being less than the width between the eyes; side
margins rounded, posterior margin slightly concave on middle; some-
what rugose, and concave on top. Scutellum yellow, with two brown
spots at the base, and an indistinct spot near the apex; slightly longer
than the pronotum. Elytra greenish brown with traces of yellow on
the claval area; transparent; margin of the clavus light brown, the
corium greenish, with a longitudinal brown marking on the middle,
extending from the margin to the second sector. Abdomen above black,
brownish at the tip, and yellowish brown beneath. Female genitalia:
Last ventral segment strongly produced to a blunt point, brown on mid-
dle with yellow borders, twice as long as the penultimate segment; pygo-
fers stout, a little longer than their width at base; ovipositor a little
longer than the pygofers. Legs light yellow, becoming brown at the tarsi.

Described from one female.
Habitat: Cape Town (Mally).

Typhlocyba elegia sp. n. (PI. XI, Fig. 2).

Form long, sharp; color light yellow, the vertex and pro-
notum marked with brown. Length 4 mm. Breadth 1.5 mm.

Face pale yellow, greatly elongated, almost twice as long as its
breadth; frons narrow, the sutures almost parallel, about four times as
long as the clypeus, which is short, and a little longer than wide. Cheeks
and lorse white, the latter long and narrow; clypeus black. Eyes black
with a whitish band on the middle. Vertex yellow, somewhat produced,
the anterior end rounded, not as long as the pronotum, and shorter than
the width between the eyes; a large brown irregular spot on the middle
of the disc. Pronotum pale yellow, with a large brown marking on the
middle, extending from anterior to posterior margin and widening con-
siderably on the middle; indistinct brown marks on the lateral margins.
Scutellum yellow with two black spots at the basal angles, and a large
black spot at the apex; brownish markings on the middle; not as long
as the pronotum. Elytra yellow, transparent, with brown markings on
the claval area, also on the corium, parallel to the claval suture; much
longer than the abdomen; middle apical cell narrow, the sides sub-
parallel. Abdomen above brown, white on the borders and bright yellow
beneath. Female genitalia: Last ventral segment twice as long as the
penultimate, strongly produced, the production being V-shaped;
pygofers strongly rounded to the sides, ovipositor strong, a little longer
than the pygofers, black at the tips. Legs hght yellow.

Described from three females.
Habitat: Cape Town, C. P. (Mally).

Date of Publication, March 17, 1916.

200 The Ohio Journal of Science [Vol. XVI, No. 5,

EXPLANATION OF PLATES.

Plate IV.

Figure I. Macropsis subolivaceus Stal. a, adult; b, face; c, male genitalia;

d, female genitalia; e, elytron.
Figure 2. Pediopsis capensis. a, adult; b, face; c, male genitalia; d, elytron.
Figure 3. Idiocerus hewitti. a, adult; b, elytron; c, female genitalia.

Plate V.

Figure 1. Agallia nigrasterna. 1, adult; 2, face; 3, elytron; 4, male genitalia;

5, male genitalia, side view.
Figure 2. Agallia cuneata. 1, adult; 2, face; 3, female genitalia; 4, elytron.

Plate VI.

Figure 1. Cephalelus infumatus Perch. 1, adult female; 2, adult male; 3, nymph;
4, face; 5, female genitalia; 6, male genitalia; 7, dorsal view of poste-
rior end of female abdomen.

Figure 2. Deltocephalus breviatus. 1, adult; 2, face; 3, female genitalia; 4,
male genitalia; 5, elytron.

Figure 3. Deltocephalus aristida. a, adult; b, face; c, female genitalia; d, elytron.

Plate VII.

Figure 1. Athysanus capicola Stal. a, adult; b, female genitalia; c, male genitalia;

d, face; e, elytron.
Figure 2. Athysanus aethiopica. a, adult; b, female genitalia; c, face; d, male

genitalia; e, elytron.
Figure 3. Athysanus eriocephalus. a, adult; b, female genitalia; c, male genitalia;

d, face; e, elytron.
Figure 4. Athysanus cyclopia, a, adult; b, female genitalia; c, face; d, elytron.

Plate VIII.
Figure L Athysanus nemesia. 1, adult; 2, face; 3, male genitalia; 4, elytron.
Figure 2. Thamnotettix karooensis. a, adult; b, female genitalia; c, male gen-
italia; d, face; e, elytron.
Figure 3. Thamnotettix. cotula. a, adult; b, female genitalia; c, male genitalia;

d, face; e, elytron.

Plate IX.

Figure 1. Thamnotettix pentzia. 1, adult; 2, face; 3, male genitalia; 4, female

genitalia; 5, elytron.
Figure 2. Thamnotettix struthiola. 1, adult; 2, face; 3, female genitalia; 4, male

genitalia; 5, elytron.

Plate X.

Figure 1. Empoasca protea. a, adult; b, female genitalia; c, face; d, elytron; e,

hind wing.
Figure 2. Empoasca hcliophila. a, adult; b, face; c, female genitalia; d, elytron;

e, hind wing.

Figure 3. Typhlocyba purpureatincta. a, adult; b, face; c, elytron; d, hind wing.

Plate XI.

Figure 1. Typhlocyba mallyi. a, adult; b, female genitalia; c, face; d, elytron;

c, hind wing.
Figure 2. Typhlocylja elegia. a, adult; b, face; c, female genitalia; d, elytron;

e, hind wing.
Figure 3. Cicadula longiforma. a, adult; b, face; c, female genitalia; d, male

genitalia; e, elytron.

Ohio Journal of Science.

Vol. XVI, Plate IV,

Eric S. Cogan.

Ohio Journ'al of Science.

Vol. XYI, Pl.\te V.

f«^^

F>c* //

Eric S. Cogan.

Ohio Journal of Science.

Vol. XVI, Pl.ate VI.

Eric S. Cogan.

Ohio Jovrxai, of Science.

Vol. XVI. Plate VII.

Eric S. Cogan.

Ohio Journal of Science.

Vol, XVI, Plate VIII.

Eric S. Cog an

Ohio Journal of Science.

Fig. 1

Vol. XVI. Pl.\te IX.

Eric S Cogan.

V\K- 2

Ohio Journal of vScience.

VOL. XVI, PLATS X.

Fig. 1

^ig. 2

i^

S

E> I'c S. Cog an.

Ohio Journal of Science.

Vol. XVI, Plate XI.

Fig. 2

Eric S. Cogan.

THE

Ohio Journal of Science

PUBLISHED BY THE

Ohio State University Scientific Society
Volume X\'I A P R I L , 1 9 1 6 No. 6

TABLE OF CONTENTS

Hills— Reames Cave 209

Fullmer— The Toledo Cedar Point 216

WiTHROW — The American Chemist and the War's Problems 219

BoHANNAN — Derived Solutions of Differential Equations 2ol

Smith — The Electrical Conductivity of Indium and Thallium 244

News and Notes 248 ,

REAMES CAVE.

Thomas M. Hills.

Reames Cave is also called Mount Tabor Cave, because of
its location in Mount Tabor. It is on the Reames farm and
owned by the Reames family, who wish it called by their name.
For these reasons the title name was adopted.

The Cave lies along the northern border of Champaign
county, in the west central part of Ohio. It can be reached
most easily, by way of the Big Four Railroad or the Ohio
Electric Railway, from West Liberty, a small town four and a
half miles to the northwest.

Mount Tabor is an elevation 1278 feet above sea level
along the eastern side of the Mad River valley. It lies between
that river and the prominent moraine of the Late Wisconsin
ice sheet that forms the eastern side of the valley from Belle-
fontaine southward.

The Cave is located at the northern end of a ridge which is
partly limestone and partly glacial drift. This ridge is a mile
and a half long, a half mile wide and eighty feet above the
stream beds to the east and west of it. It is of topographic
importance because somewhat isolated from the high morainal
ridge to the east which would otherwise overshadow it. This
isolation is partly due to the present drainage of the region
and partly to preglacial erosion.

209

210

The Ohio Journal of Science [Vol. XVI, No. 6.

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April, 19 16] Reames Cave 211

The drainage is into the Mad River valley and is mostly
surface run-off except in the vicinity of Mount Tabor, near
both ends of which and to the southward are depressions. There
is no doubt that some of these are sinks. Some, however,
may be kettle holes associated with the near presence of the
broad moraine. The abrupt ending of some small streams
in ponds near Mount Tabor, shows that there is underground
drainage in its immediate vicinity.

Geologically, the cave is located in the Columbus limestone,
a small outlier of which forms Mount Tabor. This is a small
edition of a similar situation in the double pointed hill near
Bellefontaine.

Several small quarries have been opened near the base of the
Mount, for local use. In a specimen from one of these Miss
Rose Gormley identified the following fauna: Atrypa reti-
cularis, Atrypa spinosa (?), Cyrtina hamiltonensis, Leptcena
rhomboidalis, Rhipidomella vanuxemi, Spirifer divaricatus (?),
Stropheodonta hemispherica, Zaphrentis cornicula (?), Dal-
manites calypso.

This fauna, together with the lithologic character of the
limestone, and the fact that at the cave entrance is exposed
fifteen feet of Ohio shale immediately above the limestone,
leaves no doubt as to its age. The Ohio shale at the entrance
is the only known occurrence of it on the hill. It seems to
have been protected from ice erosion, because it occupied the
bottom of a shallow sink, which subsequently enlarged and
deepened to form the present cave entrance.

Glacial drift covers the southern end of Mount Tabor in a
train that stretches out from the limestone core. The northern
end of this core was left exposed by the ice. It has the steep
slope to the north and the drift to the lee characteristic of ice
shaped hills.

Reames Cave is approximately 1800 feet long. Its general
form is that of the letter F, the entrance being at the base of the
letter and the fork 1100 feet from it. The passages run in a
northeast direction up to the fork, where one continues along the
same line and the other branches off to the north. (See map).

The width of the accessible galleries varies considerably.
The maximum is fifty feet. Where this wide the height of
all but a small passage may be reduced from a maximum of
twenty-five feet to three feet or less. The wider places are

212

The Ohio Journal of Sciertce [Vol. XVI, No. (>,

usually at the intersection of two joint planes. This is not
true of the northern arm. Its rooms are the largest in the
cave and occur along a single joint plane.

Reames Cave is one of the largest if not the largest in Ohio.
It owes its size to the extent of its narrow chambers, rather
than to their width or height. These chambers are all on one
level or nearly so. The floor at the entrance is thirty feet
below the ground surface. It descends gradually to the north-
eastward, but so gradually that at the extreme end of the cave

Figure 2. The Crystal Chamber wilh eokimns of iron o.\ide and

calcium carbonate.

a descent sixty-five feet below the surface is unnoticed. Most
of this descent is along the eastern arm of the Y.

At the extreme end of both branches the floor of the cave
is quite muddy, due to the constant dripping from the roof, at
least in part. This is due to the fact that the cave in its north-
easterly course passes beyond the Hmit of the Mount Tabor
hill and is partly under the valley to the east of it. While the
surface drainage into this valley from Moimt Tabor carries
off most of the water, enough descends through the mantle
rock to give an abundant supply for solution and deposition
in the cave.

April, 1916] Reames Cave 213

The rooms are small and narrow near the entrance, but
increase in size toward the inner end. They follow a northeast-
southwest joint plane which can be seen along the roof. Figure
2 shows one of these joint planes. The "Crystal Chamber"
pictured is not the main gallery, but runs at right angles to it.

Solution has widened the joint plane along layers that are
decidedly saccharoidal in texture. This expanded area is
usually near the roof of the cave. The cross-section thus formed
resembles a plus sign, the lower end of which is partly filled
with residual fragments and sticky clay. At certain places
solution along the bedding planes far surpasses that in the other
directions and the larger rooms such as the Crystal Chamber
(Fig. 2) and the Graveyard (Fig. 3) are produced.

The exact location of the cave among the zones of the
Columbus limestone can not be stated with certainty, but it is
thought to be near the base of the formation, probably in
zones B and C of Stauffer.* The walls are coated at most
places with deposits, but the abundance of corals in the roof,
indicating zone C, and the saccharoidal layers below, which
in the upper part contain many cherty nodules, with a general
scarcity of fossils, and the massive character of the strata
agree with the description of zone B.

The concretions in the saccharoidal layers stand out prom-
inently along the upper part of the walls of the cave. They
deserve special mention because of the suggestive names that
have been given them, such as "Beef's Heart" and the "Ham."
In size they vary from a few inches to several feet in diameter.

The deposits on the walls and roof are of two kinds, calcium
carbonate and iron oxide. These have been and are being
deposited contemporaneously. The walls are coated with
alternating layers of them. At some places, as in the "Flag
Room" these are arranged in vertical stripes, while at others
the calcite is the present outside coating which gives the white
color of the "Milky Way" and other similar passages.

One peculiarity of the iron deposits is the arrangement into
a cell-like structure resembling a honeycomb, or better the leaf
scars of a Lepidodenron. The calcite forms the comb and the
iron oxide the honey of the first illustration. This can be seen
imperfectly, to the right of the stalactites in the picture of the

*Geo]ogical Survey of Ohio, Bulletin 10, pp. .36-37.

214

The Ohio Journal of Science [Vol. XVI, No. 6,

Crystal Chamber, Figure 2. It occurs on the walls and roof
of the cave at many places, resembling a structure of organic
origin, though that does not seem possible. No explanation
is offered. In Figure 2 stalactites of iron oxide, the darker

Figure 3. "Evangeline and Gabriel."

columns in the inner part of the recess, and calcite, the lighter
columns, shows the close association of these two minerals.
The change in the diameter near the middle of the column
at the left in the same illustration, is characteristic of many

April, 1916]

Reames Cave

215

of them, especially the larger ones. It occurs in those composed
of both minerals and those of only one. A constriction should
occur where stalactite and stalagmite meet. Most of the large
stalactites show two however. The question might be raised
whether an increased water supply would cause more rapid
deposition. This might be brought about by glaciation or a
number of other ways. Figure 3 of the stalactite and stalagmite
"Evangeline and Gabriel," two of the largest columns in the
cave are without any suggestion of constriction. They are
not, however, in the main cave, but off at the extreme end of a
narrow side branch which is quite dry at present and may have
been so for a long time.

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The smaller stalactites are simple in form. Hundreds of
them, about the size of a cigarette, are hollow thin walled tubes,
that hang from the roof in the wider part of the cave. They are
still covered and filled with water and probably started their
growth at a not distant past. The larger ones are from three
to five feet long. Figure 4 of the "Graveyard" is a good
illustration of the abundance of the small ones.

The time when the cave began to be formed is unknown.
The only evidence as to its age is derived from comparing it
with other solution cavities in the Columbus limestone, known
to be pre-glacial.* These are so much smaller that it seems
probable the cave was in existence long before glaciation.

The cave had no surface opening until in August, 1897, when
the ground sunk at the present entrance.

*Hubbard, Geological Survey of Ohio, Bulletin 14, p. 63.

THE TOLEDO CEDAR POINT.

E. L. Fullmer.

Several projections of land in Ohio are known locally as
Cedar Point. The one here briefly described is in Lucas
County on the south shore of Lake Erie and just east of the
entrance to Maumee Bay. It is some ten miles from Toledo.
Here a large tract of low and swampy land is known as Cedar
Point. From the accompanying map based on the United
States topographical map of the area an idea of the location
and character of this region may be obtained.

It may be seen that there is a large tract of swampy land
extending back from Lake Erie as much as two miles in places.
A considerable part of this swamp lying to the south and east
of, C, has been reclaimed. Dikes were built across the swamp
and the excess water pumped out; large ditches or canals
being used to drain the water to the pumping plant. Good
crops of onions are now grown on this reclaimed land.

Just inland from the swamp is a low lying tract, H, of very
level land; the surface of which lies but a few feet above the
water level in the lake. Ward Canal, W, is a drainage channel
cut through this region. When seen by the writer the surface
of the non-flowing water in this canal was not more than four
feet below the surface of the ground at a distance of three
miles from the lake. Of course this level varies somewhat
with changes in the lake level and no doubt the water in the
canal rises in times of rainfall as some of the higher land still
further inland is drained into it.

Extending all along the swamp on both the bay and the
lake sides is a narrow low sandy beach. It is from fifty to two
hundred and fifty feet wide and the highest parts are but little
above the reach of waves of violent storms. This beach
extends in an unbroken line except for one channel, O, opening
into the swamp from the lake. This channel is a little over a
mile from the extreme end of the land, B, and is a deep water
course perhaps some three hundred feet wide where it enters
the swamp. It extends back a considerable distance into the
swamp and is no doubt kept open by the currents set up as the
water flows into and out of the swamp with each change in
the level of the lake.

216

April, 1916] The Toledo Cedar Point 217

In some of the wider parts of the beach a narrow sand
plain has developed, on portions of which Cottonwood has
gained a foothold and has formed a few small groves of half
grown trees.

The writer had an opportunity to visit this region in the
summer of 1915 and spent two days, Aug. 30 and Sept. 1,
collecting botanical specimens upon the beach. The following
list of plants collected will show the nature of the flora, although
the list of herbs could be much extended. No Cedars or other
Conifers are now growing in this region and I was unable to
learn the reason for the name Cedar Point being applied to it.

Trees :

Acer rubrum L. — Three small trees only found.
Catalpa sp. — One specimen two feet tall.
Fraxinus pennsylvanica Marsh — A few small trees.
Populus deltoides Marsh — Abundant.
Platanus occidentalis L. — Three small trees.
Gleditsia triacanthos L. — One specimen.
Celtis occidentalis L. — One small specimen.
Salix amygdaloides Anders — Abundant.
Salix interior Rowlee — Abundant.

Shrubs:

Cornus amomum Mill. — Three clumps.

Rhus glabra L.

Rhus hirta (L) Ludw.

Ribes americanum Mill. — Infrequent.

Sambucus canadensis L. — Infrequent.

Woody Vines:

Parthenocissus quinquefolia (L) Planch. Common.
Vitis vulpina L. — Common.

Herbs :

Astragalus carolinianus L. Heliopsis scabra Dunal.

Asclepias syriaca L. Melilotus alba Desv.

Apocynum sibiricum Jacq. Oenothera biennis L.

Ambrosia trifida L. Physalis sp.

Cakile edentula (Bigle) Hook. Solidago serotina Ait.

Cenchrus tribuloides L. Spartina michauxiana Hitch.

Clematis virginiana L. Solanum dulcamaria L.

Chamaesyce polygonifolia (L) Small. Tinaria scandens (L) Small.

Falcata comosa (L) Kuntze. Verbascum thapsus L.

218

The Ohio Journal of Science [Vol. XVI, No. (),

Figure 1. Map of the Toledo Cedar Point, showing the swamp beyond the
point B; W, ward canal; H, low ground near swamp; O, open channel into swamp;
A, B, C, sandy beach.

THE AMERICAN CHEMIST AND THE WAR'S

PROBLEMS.*

James R. Withrow.

A volume could be written upon this subject if one possessed
the power to assemble the material. The new problems which
have arisen; the old ones which have become acute because of
changed conditions; the splendid way in which the problems
have been met where they were a matter of invention or skill;
the new methods and processes which have sprung up as though
born fullgrown ; the many old ones which have been improved,
altered and utilized in new connections; the way in which the
chemists of the country have risen to emergencies which have
compelled them to manufacture products in whose manufacture
they had had no prior experience, would easily fill entire chapters
in such a volume. Even so, no earthly progress, achievement or
consideration can lift the pall which settles over us when we
permit our minds to dwell upon the spectacle of this war. And
whose mind can be diverted from it for any length of time? He
must indeed exist far below the kindling-point who does not
resent and despise with all his soul, the philosophy and ideals
which made it possible. It would be out of place therefore, to
consider our subject from the point of view of achievement, or
felicitation, on any alleged good which has come to the science
of chemistry because of the war. Surely no one would want
progress at such a cost to his fellow man. We approach the
subject rather in a spirit of thankfulness that we have been
enabled to save something out of the wreck, and that our
experience had prepared us in advance so that we have been
enabled to prevent the collateral business and economic trag-
edies of the war from spreading universally. It is not in any
spirit of gladness, therefore, at the evil providence which has
fallen upon our European neighbors, that we recognize that
this war has exalted the importance of chemistry in the minds
of those who had not much opportunity hitherto to appreciate
its value, nor is it with any jubilation that we take pleasure as
chemists in meeting our new problems and emergencies arising
from the war.

* Address before Section C, American Association for the Advancement of
Science, Columbus Meeting, Dec. 30, 1915.

219

220 The Ohio Journal of Science [Vol. XVI, No. 6,

The satisfaction to many Industrial Chemists in the last
two years of being able to contribute to the solution of these
problems and of being conscious of the salvation of many
businesses from financial ruin through the exercise of their
chemical experience, has seldom been so widely distributed as
it now is. What an inspiration it would be to read, spread out
upon the pages of such a book, as we have mentioned, the
chemical successes, big or little, of the past two years. It is
not likely that many of them will be known for a while because
of the fact that business caution forbids their publicity in many
cases, and the vigorous campaign of destruction of equipment
and diversion of supplies which stoops at nothing which will
hamper export from this country, makes silence a necessity in
self defence.

The problems of the war are of tivo kinds, those due to changed
conditions and those arising from supplying munitions at high
speed. Among the former are changes in raw materials made
necessary by the failure of imports or by unusual consumption
of raw material in other channels such as for products not here-
tofore manufactured in this country to the extent made nec-
essary under present war conditions. These changed circum-
stances were also due in part to new demands for materials and
products, which have arisen in the complete rearrangement of
things that has come about in many circles since the war began.
The other line of war problems which have arisen, those directly
connected with munitions supply, are frequently of a difficult
nature. All these various problems, however, have been met in
practically every case with a degree of success which has
surprised even ourselves.

Naturally one of the first serious effects of the war on
American industries was the stagnation produced by the
enforced cessation of exports in various lines. Such things as
rosin, turpentine, petroleum products, acetate of lime and
methyl alcohol were seriously affected for a varying length of
time. Then the demand for munitions became, for instance,
the wood distillation industry's salvation and with great
celerity, acetone plants were attached to many of the works of
this industry and the high prices which the products of the
industry demanded have brought unprecedented prosperity to
it and have correspondingly hampered progressive improvement.

April, 1916] American Chemist and the War's Problems 221

Production, not efficiency, is at present the slogan for this and
many other industries. Set-backs of the nature cited usually
take time for readjustment and frequently the chemist is a
material factor therein. The producer himself is often com-
pelled to add the next manufacturing step to his own operations.
The acetate maker for instance, tends to enter acetone man-
ufacturing. Where the new demands were ample, these attempts
have succeeded and the war's conclusion will find an increased
tendency to manufacture at the source.

The set-backs to industry arising from the disturbance in
exports while they were important financially were minor
matters compared with those arising from such changed con-
ditions as failure of raw materials or their curtailment by
absorption in new or abnormally expanded industries. It is
here that the chemist is needed most and it is here that he has
been of immeasurable service, and has met the problems that
have arisen in wonderful style. He was seriously hampered at
first by the uncertainty as to the facts. The fundamental thing
in every industry is the market. At first much damage was
wrought and delay produced by false reports as to stocks on
hand and supply, particularly, of imports. Much withholding
of goods for higher prices was practiced and even yet the
pirates of commerce seek ways and means of evading contracts,
even on deliveries of goods which they were receiving without
cessation, so as to avail themselves of the inflated market prices.
Some clever work by consumers trapped at least some of these
unscrupulous brokers and sellers. All manner of fictitious
prices were demanded of those unfamiliar with the facts and
attempts were even made to influence the Washington Govern-
ment to activity against the British blockade through the use
of untruthful statistics regarding dyes.

As soon as the true status of market and supply became
reasonably certain many changes were effected which will give
gradual and probably ultimate relief. On every hand we see
chemical activity without end. Products like synthetic phenol
and barium salts not made in this country before the war are
now made in large amount. Great expansion in production has
taken place in the case of such material as benzol, toluol,
aniline products, naphthaline, carbon-tetra-chloride, acids,
alkalis, chlorates, bichromates and even oxalic acid. With all of
these we were largely or in part dependent on imports, but have

222 The Ohio Journal of Science [Vol. XVI, No. 6,

almost ceased to be so since the war began. Fertilizer plants
erect their own sulfuric acid works and insecticide makers their
own arsenic acid plants. Textile mills make their own bleach.
Numbers of manufacturers replace potash compounds by
sodium compounds and to my own surprise at least, often
with great improvement in results. Professor Watts has just
told you this afternoon how the ceramist is rendering this
country less and less dependent upon imports in that field by
scientific purification and utilization of domestic clays. Man-
ufacturers of numerous miscellaneous chemicals and phar-
maceutical preparations proceed to refine and produce their
own crude raw materials and intermediates. The dye famine — -
for it is real in certain quarters, stirs up corporations with
capital of hundreds of millions to enter the field. One of these
new companies has installed half a million worth of machinery
in the last few weeks. Indigo and other dyes are being made
in nearly half ton batches which will soon expand to several
ton size. Where formerly was the most peaceful of occu-
pations even fertilizer manufacture, every effort now goes
to the making of munitions. New plants spring up at the beck
and call of the new conditions such as the world has never
seen. Think of a battery of one hundred nitric acid stills
each charging 4,000 lbs. of sodium nitrate three times a day.
Think of the sulfuric acid required and the nitric acid produced.
Think of the fact that this one of a number such, (the largest
nitric acid plant in the world it is said), is a plant which a year
ago did not exist except in the minds and plans of a group of
chemical engineers. How little are we able to comprehend
the reality of producing 1,000,000 pounds per day of gun-cotton
where a year ago was merely pine-woods. What does it mean
with reference to design of plant, erection and operation to
anyone who has not managed chemical engineering operations,
to recount the engineering operations involved in this enormous
production of gun-cotton in a single plant? Work that is
conducted in ten to fifteen parallel procedures or "cotton-
lines," which with their accompanying accessories, include
cleaning and alkali digestion of the cotton; bleaching with
chloride of lime; manufacture of sulfuric acid for the production
of nitric acid and "mixed acid;" nitration of the cotton in
thirty pound batches; the hazardous wringing and hasty sub-
merging of the cotton in water, to avoid the consequences of

April, 1916] American Chemist and the War's Problems 223

heating by too slow dilution of the strong acid held spongelike
by the cotton; the conveying of this material in the cotton-line
to the washers where the remaining acid in the tube-shaped
cotton fibres is removed ; and finally the removal from the water
as wet or damp gun-cotton, the commercial product of many
plants. This end product of course is but the beginning or
raw material for the various nitro-celluloses, smokeless powders
and other high explosives. Yet this scale of operations is not
going on in just one plant of this kind or even in this one
industry. This is a sample of what is happening every day in
the shape of the American chemical engineers' answer to the
question, how are you meeting the war's problems?

At some of these things we are permitted to take at least a
peep. No one man can know all of even such gross develop-
ments, and practically every chemist we meet has his enthusias-
tic story of the progress in his own and familiar fields. We all
do know, however, that if this is the character of the outward
developments, there must be legions of quiet research and other
experimental attacks on the new problems, and literally
hundreds of solutions being worked out for minor problems in
factory and plant, not to speak of the vast amount of work
in other departments of chemistry made necessary by all these
things. Then, too, there is the ever verdant crop of interesting
suggestions, revolutionary changes and inventions throughout
the list of the chemical industries. In fact they are doubly
numerous and aggressive under the stimulation of such a time
as this. It is never wise to predict their success or failure until
even years have elapsed in many cases. So that the lecturer
who wishes to entertain his hearers with pleasant and surprising
intellectual gymnastics in the shape of the newest and most
wonderful achievements in industrial chemistry is safe from
apparent error for from three months to three years, if he picks
his illustrations well. At the end of that time he can dodge
criticism for misjudgement by referring the back-fires to poor
business management, insufficient capital, tariff, trusts and
sometimes poor engineering. It is true that a large number of
these new things never make good. It is equally true that some
of them will make good and that all of them indicate progress,
for they are striving, and progress comes by striving.

It is equally true also that many of the chemical experiments
which are in successful use under war conditions, will auto-

224 The Ohio Journal of Science [Vol. XVI, No. 6,

matically step aside when normal conditions resume. It is
fundamental industrial chemical intelligence that a procedure
which is ridiculous under some conditions may be a God-send
under others. We do not expect every change installed to be
really normal progress for it will not be so in the ordinary
sense at least. On the other hand, it would be wrong also to
say that the mushroom plants producing munitions are not
signs of progress. They unquestionably are not such signs
in as far as they are temporary. They do not measure true
expansion in their respective fields. He would be a novice
or singularly blind, however, who did not see that the con-
struction of such plants on the undreamed scale I have already
mentioned, not to talk of the new materials and procedures
which have been incorporated into many of them, makes for
greatly enlarged experience in chemical engineering designing,
construction and operation. It is easy to see the pressure these
things are going to exert upon the future development of
American chemical industries. The American chemist's exper-
ience is becoming greatly expanded and the significance of this is
apparent when we consider that engineering progress is a func-
tion of demand, and skill or experience in solving problems.
The demand increment is ever expanding with the development
of the country. In addition the skill acquired in the pro-
duction of munitions is a valuable potential asset for defense
should such a necessity ever arise. Such preparedness is highly
to be desired. Then too at the close of the war when the output
of these plants is no longer needed for that purpose, their
equipment and intelligence will be directed into whatever
field promises most. Already some of these concerns are
assured that some of their products will find a continuous
demand after munitions' manufacturing ceases, which will
be some little time after actual hostilities are at an end. The
field of dye production is already attracting some of them.
Without doubt the industrial rearrangements to follow the war
will leave us much better situated in our ability to cope with the
problems of chemical production. At any rate powerful
financial interests will attack these problems as they never
have been attacked before. These interests will constitute
another great force, which will be particularly effective after
the war. When they seek new outlets for materials, such as
alcohol, benzol and acids, whose production they are greatly

April, 1916] American Chemist and the War's Problems 225

accelerating at the present, the gasoline and other problems
will be greatly affected. These interests will be found after
the war lined up behind the industrial chemists who have been
struggling for years against all kinds of unfair competition and
disreputable depreciation. Then again, any change in process,
be it ever so time-worn, chemistry or transient in its nature, if
it actually is put into successful operation under the then
existing conditions, must of necessity push out the boundaries
of experience to greater and greater distances and make us
better able to meet the problems of the future. Chemical
engineering is like any other division of engineering, it grows
by what it accomplishes. In this proof of ability to meet a
transient emergency the American chemist is certainly reaping
a hundred-fold, from his unadvertized care in the meeting of
his industrial problems of the years which have gone before.
Individual cases of progress and development which I have
mentioned it is easily seen are rarely of great importance in
themselves. We have not been revolutionizing on a great
scale, nor have we been jumping at once into great new national
industries, but we are rather directing the normal steady gait
of our progressive industrial development with keener per-
ception toward more complete selfcontainedness, and thorough
industrial preparedness. Some of the industries mentioned
which receive much public attention are of relatively little
importance compared with many other items affected. The
dyestuff shortage appears to annoy many, but the complaint
is out of all proportion to the facts and the damage done,
compared with that of other commodities. We import annually
for instance, $9,000,000 in coal tar dyes per annum and if we
should make them all ourselves — which we will only gradually
approximate — we would only increase our chemical manufac-
tures two per cent, and our total manufactures five one-
hundredths of one per cent.

Though we have made reasonable headway on our problems
we are keenly aware that much remains to be done. We do not
expect to set the market right in the dye or other matters in a
year or two. These developments take time and have always
taken time. Neither should we deceive ourselves or the public
into thinking because of what we are doing that we could turn
out without the most careful and detailed previous planning,

226 The Ohio Journal of Science [Vol. XVI, No. 6,

adequate munitions for our own defense "in sixty days" to
supply the "two million men who would spring to arms" as
we so often hear would happen in that undesired emergenc3^

It would be interesting to discuss in detail some of the
transient as well as probably permanent advances, where they
happen to be a matter of personal knowledge, if it were wise
to hand information to the assassins who lie in wait to hamper
some of them, for military reasons. It might be well, therefore,
to spend just a little time in emphasizing some general con-
siderations which are connected with this subject.

There is little use in attempting to disguise the fact that the
present war is a struggle between the industrial chemical and
chemical engineering genius of the Central Powers and that
of the rest of the world. Quite irrespective of the war's origin,
aims, ideals or political circumstances, these are the cohorts
from which each side derives its power.

When we consider the strategic position of the Central
Powers themselves, their capable education and training, their
system of government, which, no matter what we may think of
its selfish effect on the world as a whole, we must admit makes
for more effective concentration upon its own governmental
objectives, among which preparation for war is merely one of
its manifestations, when we take into account all these things it
must often appear to us that the greatest outstanding feature
of the past two years is the miracle of the Entente Powers
resistance to the terribly efficiently prepared onslaught of the
Central Powers. This resistance is due, to an extremely large
extent, to the efficiency of the chemists of the neutral and
Entente nations. The chemists of the Entente Powers and of
America have risen to the emergency as no chemists have ever
done before in the history of the world. Confronted at the
beginning of the war by antagonists whose munitions industry
for years had been developed for just such a contingency,
these chemists have in less than two years built up a rival
industry at least as strong. Plant after plant has sprung up of
such perfection of design and operation that one wonders how
the mind of man was capable of such engineering. Though the
speed with which these new and unexpected problems have been
solved may appear surprising, no one who is informed about
the progress and development of industrial chemistry in this

April, 19 10] American Chemist and the War's Problems 227

country, could have reason to doubt that American chemical
engineers and industrial chemists would rise to any emergency
which it was within human power to meet. They have already
and will continue to live up to what we have a right to expect
of them, in view of their past successes. We would be surprised
if a similar degree of success did not crown the efforts of the
chemists of the other countries, France, Britain, Italy, Germany,
Austria, Russia, for it has never been the habit of American
chemists to boastingly claim superiority because of any advan-
tage, real or imaginary, with which they, like any group, are
apt to be blessed for a greater or less period of time. We
have always appreciated chemical contributions to progress
from whatever source they have come and praised unstintingly
the individual wherever he may be who has taken a distinct
step forward, for we firmly believe this is an important help in
advancing the progress of the science.

These general developments are naturally not a matter of
public information, except attention is called to them. The
chemist works almost entirely beneath the surface of things
and only in a few spectacular cases is public attention drawn to
his work. It is quite natural therefore that appreciation and
praise of foreign chemical achievement and particularly our
consistent praise of German achievement to our students by our
university teachers of chemistry have been misunderstood, and
have prepared a fertile field for foreign propagandas to establish
a false impression of the superiority of certain groups of foreign
chemists. We would scarcely object to a good-natured adula-
tion of anyone's fatherland and its achievements. Such things
always contain good and are stimulating to everyone, and it
is a pleasure to hear them when free from arrogance, even when
the adulation contains little that is new or even strictly true.
When, however, this privilege is abused so that the point of
superiority must be made by depreciating American efforts
it has a vicious positive result upon the minds of the uninformed,
and at times causes great financial loss to them.

If the shortcomings of American chemistry were frankly
discussed and compared with foreign successes in a chemical
publication, some help might thereby be given to those who
could derive benefit from it. When this is not frankly done,
but simply issued as an incidental depreciation of American

228 The Ohio Journal of Science [Vol. XVI, No. 6,

chemistry, particularly when discussing foreign chemical achieve-
ment, and still worse when in a non-chemical publication, the
object can scarcely be rated as creditable.

A good illustration of this is an article published by the
Review of Reviews for August, 1915, upon "What German
chemists are doing to make Germany self-sustaining," by Hugo
Schweitzer, who the editor humanely states is an American
chemist. Considering the avowed purpose of the article as
attempting to influence American public opinion to stop "a//
exports to all belligerent nations," the article gives an interesting
appreciation of the German chemist's efforts to meet their
present problems, but commences to wind up as follows :

"Thus the horrors of war, through the ingenuity of the Ger-
man chemists, are promoting the legitimate industry of the
nation, rendering it more and more independent of foreign
conditions, and keeping in the country vast sums formerly
spent for imports. Unfortunately and unexpectedly we cannot
record similar advantages for the United States, although we are
enjoying peace.'' The inaccuracy of the last statement we hope
is no measure of the truthfulness of the article as a whole. If
the myth of the overwhelming industrial chemical superiority
of German chemists ever was really believed, in that country,
the military forces of the Central Powers at least, must marvel
at the reason the supposedly inferior foreign industrial chemists
have been able to display such astounding ability and speed in
meeting the problems of munitions production, particularly too
in countries where governmental mobilization of industries was
unknown before the war and in America at least, still is unknown.
At any rate, it has become evident that lack of advertisement
is no sign of lack of ability or activity, and that ability to handle
science skillfully and powerfully is not confined to any race or
nation. We do not feel that there is much to be gained by
confuting claims of the chemical superiority, of foreign coun-
tries in this and other similar articles for it is curious how this
war has developed farsightedness to the extent that such
Americans can see only the chemical developments abroad.

I hope I have made it clear that it is the abuse of a privilege
against which I speak, and not against individuals, for we do
not let such personal attacks affect our regard for individual
Germans any more than we allow our opinions on the history

April, 1916] American Chemist and the War's Problems 229

of the past two years to affect this regard for such individuals.
Everyone of us knows Germans who are the most whole-souled
and kindly men — who we are grateful to know and who scorn
to be guilty of, or take advantage of, such chauvinism. Such
depreciations of American efforts will bury themselves, without
any assistance from us, and I only emphasize them here to call
the attention of teachers of chemistry to the fact that we owe
protection to the business community and the public against
such misrepresentation. We should never cease our appre-
ciation of foreign chemists of whatever nation, but in addition
it is our duty first to inform ourselves and then our students
upon what our own chemists have done to solve our problems
in this country. We have been able to blame our shirking this
duty in the past upon the fact that it was easy to get informa-
tion about foreign chemical achievement and no one seemed
anxious to give publicity to American development. We as
teachers have certainly done little to remedy this condition.
The American Chemical Society, however, has spread the
results of American effort before us and made them accessible
in its Journal of Industrial and Engineering Chemistry for the
last two years, in the shape of a series of addresses on the
chemist's contributions to American industries. There are
other addresses in these same volumes profoundly informing
along these lines and this is particularly true of the Perkin
Medal addresses each year in the same journal. In addition.
Professor S. P. Sadtler in the American Journal of Pharmacy
for October, 1915 (an address before the National Exposition of
Chemical Industries), in giving popular information along this
line limits himself entirely to chemical industries originated as
well as developed by American chemist and Edgar F. Smith's
History of Chemistry in America, but recently issued, should
be read by every student of chemistry.

None of this work is in any sense a vain glorious adulation of
the chemist as some super-being nor is it an attempt to compete
in the questionable game of lauding one nationality above
another. It is merely a matter of a belated form of education
which our universities and chemists hitherto have largely
denied to the American business man, and which he has a right
to expect of them. The record is one for which we have good
reason to be thankful and, as we teachers no longer have the

230 The Ohio Journal of Science [Vol. XVI, No. 6,

excuse of ignorance about American progress, we are at fault,
if the rising generation has not an appreciation of the progress
of chemistry in America, commensurate with the high level of
its development.

In conclusion then, let us take courage from the fact that
though much damage has been done to us and our industries by
the war, our efforts at salvage benefit us as experience, power
and preparedness. We have seen that the chemists of America
have met the war situation well and do not require defense at
the hands of anyone. It becomes increasingly evident that
business is awakened to the value of chemistry as a source of
power and wealth as business has never had occasion or oppor-
tunity to be hitherto. Let us hope also that not only the
spectators but also all the combatants may learn, even if
impelled by bitter war's experience, to appreciate the worth,
each of the other, and that all nations are "made of one blood
to dwell on the face of the earth."

DERIVED SOLUTIONS OF DIFFERENTIAL EQUATIONS.

(Short Methods).

R. D. BOHANNAN.

When F(m)=0 has n roots equal a, then F(m)=0 and its
first n — 1 derivatives have this root in common. So if F(m, x)
is a solution of a differential equation, for different values of m,
then, if n values of m are equal to a, are also the first n — 1
partial derivatives of F(m, x) with respect to m also, generally,
solutions, when, after differentiation, m is changed to a.

Case I.

(a) Linear differential equations with constant coefficients,
second member zero.

y = gmx

is the solution.

If (D — a)" is a factor of the first member, using the symbolic
method of solution, then

pinx vpinx v2pmx •vn— Ipmx

are all solutions, when m is changed to a, these being the partial
derivatives with respect to m. Multiply each of these by an
arbitrary constant and add for the general solution correspond-
ing to (D — a)".

(b) When D^+a- is a factor of the first member,

y = sin mx, y = cos mx

are solutions, when m is a.

When (D- + a-)" is a factor of the first member,

sin ax, x sin (7r/2 + ax), x^sin (27r/2 + ax),

x'^-i sin ( (n — 1) 7r/2H-ax),

cos ax, X cos {ir/2-\-a,x, x^cos (27r/2 + ax),

x"-i cos ( (n — 1) 7r/2 + ax)

are solutions.

(c) When (D — a)2+b- is a factor of the first member,

y ^gmx

is a solution, when m is changed to a+bi and a — bi, giving,

y = e''-^ cosbx and y = e^^ sin bx
as solutions, after addition and subtraction.

231

232 The Ohio Journal of Science [Vol. XVI, No. 6,

When ( (D — a)-+b-)" is a factor of the first member, the
(n — 1) partial derivatives of e'"^ with respect to m,

ypinx v2pmx -y" 1 pnix

are also solutions, when m is a + bi, or a — bi, giving also as
solutions,

xc'^sin bx, xe^'^cos bx, x^e'^^'sin bx,

X2gaxcQg ]3x^ ^ j^n-lgax g^j^ ^x,

X^-l gax cos bx.

Multiply each by an arbitrary constant and add.

Case II.
For the homogeneous linear differential equation of the form,

y = x'"
gives X" F(m) =0, and if m — a is a factor of F(m), a solution is

y = x'"-
The partial derviatives of x", with respect to m, are

X'" logeX; X"' log-eX; x"' log^x, etc.
Thus if (m — a)" is a factor of F(m), the solutions are,

y = x% y = x'^ logeX, y = x^(logex)2,

y = x^(logex)"-i

Multiply each by an arbitrary constant and add.

Case III.

(a) In (a) of Case I, if the second member is e"'"" (instead of
zero) the particular solution is

pmx pmx

D — a m — a

mx

for the equation (D — a) y = e
This fails when m = a.
All failing cases of this sort will give a solution when treated

like the form in calculus (differentiating as many times as the

factor occurs, omitting differentiation as to factors giving no
trouble, just as in the calculus problem).

April, 1916] Derived Solutions of Differential Equations 233

(1) d

dva

(gmx)

y

= = — = xe™"^ = xe^''

m— a d , ,

n (m a)
dm

(2)

y

gmx y^Qva^ x^e™^ x^e'^'^

(m-a)2 2(m-a) 2 2

(3)

y

gmx x"e^''

(m — a)'' n

(4)

y

gmx

= , 2 , - . „v . ,^s, , when m = 2
(m2+5m+3) (m — 2)2

xemx x^e™-^ x^e ^^^

(17) 2 (m-2) (17) (2) 34

(b) For (D2 + a2) y = sin (mx)

(1) _ sin (mx) _ sin (mx)
^ ~ D2+a2 ~ -m"-+a2

This fails when m = a, but

(1) d , . , ..

— — (sm (mx) ) ,

_ dm _ X cos (mx) _ x cos (ax)

^ ~ 5 X " I 2^ ~ ~2m ~ -2a

5m

(2) ^^ _ cos (mx) _ cos (mx) _ x sin (mx) _ x sin (ax) ,
when m = a.

^ D2+a2 a--m- 2m 2a

(3) _ sin mx _ sin mx

^ ~ (D2+9) (D2+-i) ~ (9-m2) (4-m2)

For m = 2,

_ X cos mx _ — X cos 2x

^ ~ 5(-2m) 20

For m = 3,

_ X cos mx _ X cos 3x

^ ~ (-2m) (-5) ~ 30

(4) sin mx

^ "" (D-^+4)2 ' '' '^^

sin mx x cos mx — x^ sin mx

(4-m2)2 (-4m) (4-m2) (-4m) (-2m)

— x^ sin 2x
32

234 The Ohio Journal of Science [Vol. XVI, No. 6,

(5) sin mx , , -.

V = wnpn m = 'J.

- fD^+ '"^^

sin mx x cos mx — x'sin mx

(4-m2)^ 3(-2m) (4-m2)2 |3j-2m)2(4-m2)
— x^cosmx x^cos 2x

3

|3_(-2m)^ !3_(4)
(6) sin mx , ,

x"sin (n— +mx) x"pm (n-+ax)

Similar treatment when the second member is the cosine.

Case IV.

Linear differential equations, constant coefficients, second

member a constant.

This is a particular case of (a) Case III.

d^v dv

^_5^y +Gv = 4 = 4e-

dx- dx

_ 4e''^ _ ^ _ 2,

■'• ^' ^ D^-TdD+G ~ 6 ~ 3

when D = 0, is the particular solution.

Case V.

Failing case of Case IV.

d^y - d y
dx^ ' dx

4gmx

\^ =

m^ — 5 m

is the solution when m = 0.

4x6'"''

.-. As in Case III, y = ^; -, when m = 0

2m — 0

4x

or, V = —'

o

is the particular solution.

April, 1916] Derived Solutions of Differential Equations 235

Case VI.

The non homogeneous linear differential equation.

The solution is usually two or more series gotten from.

y = x"^ (Ao+Ai, x^i+As x"2+A3X"34- etc.), (S), (where
A], A2, A3, etc., are functions of m, and each of all the preceding
by giving m particular values gotten by substituting x'" for y
in the given equation.

Calling (S), y = F (m, x), then, in case of two equal roots

^^"^'^^ y = -^F(m,x).

dm

a solution, if, after differentiation, m is given the value of this
root. And in case of three equal roots, is also

a solution, and so on.

Suppose k is a particular value of m, and that x"", Ai, A2,
etc., are all expressed in powers of m — k:

x™ = xk (l + (m-k) logeX+ (m-k)^ log^eX+ etc.)

Ao = Ao(l+Zero (m-k)+Zero (m-k)2+ etc).
Ai = Ao(ai+bi (m-k)+Ci (m-k)2+ etc.)
A2 = Ao(a2+b2 (m-k) + C2 (m-k)-+etc.),

and so on.

Substitute these values for the A's in S and calling
l + aiX"i-f-a2X"2-|- etc., the A-series; the coefffcient of m — k, the
B-series; that of (m — k)^ the C-series, etc., (S) becomes:

y = Aox'^ (1+ (m — k) loge x+etc.) times

(A-series+ (m — k) (B-series) + (m — k)- (C-series)
+ etc.) = AqX*^ (A-series)
+AoX^ ( (A-series) loge x + B-series) (m — k)

+ i\o x'^ ( ~ log2eX+ (B-series) logeX

+ C-series) (m — k)-4-etc.
In case m has the value k only once,

y = Ao x^ A-series (1)

is the solution.

If m has the value of k twice,

y = BoX'' ( (A-series) logeX + B-series) (2)

is also a solution. This is

y = ^F(,n,x)

when m = k.

y = ^^7;;;yF (m, x) when m = k

236 The Ohio Journal of Science [Vol. XVI, No. 6,

And thus is

y = x'' (Ao + Bo logex) A-series +BoX'' (B-series)
a solution.

And in case m has the value k three times, then in addition
to the solutions (1), (2), is also

y = Cox'' -^ ^ log\x+ (B-series) logeX+ (C-series)

a solution. This is

dm.
And thus is

Co

y = x'^ (Ao+BologeX+ -^log\x) (A-series)

+x'^(Bo+Cologex) (B-series)
-\-\^ (C-series)

a solution. And so on.

It is quite easy, in any particular case, to obtain the B-

series, C-series, etc., from the A-series, far easier than by

the method usual in the texts (compare the following with

Johnson, p. 181 to 194).

Illustrations.

(a) Series starting with x°.

d^v dv
dx'' dx
y = x"', gives m-x"^-i-|-x™ = 0 (1)

We may assume an ascending series, starting with x°,
consecutive powers diJffering by unity.

00

Ifj|we assume y = S ArX'"+'',

0

then by (1)

(m+r)2A.-fA,_i = ()

For> = 0, A, = - Ar-i . ^ (3) ;

(3) Ogives the A-series,

X , X- x^

y-1 12 + 12.22 12.22.32. "^^^^*

April, 1916] Derived Solutions of Differential Equations 237

1

If we differentiate the m-factor, — z^, ^2' occurring m

(2), we have

/I

y (m + r)^ / \m+r
And for m = 0, this is

And the n*'' term of the B-series comes at once from the
(n + l)*'' term of the A-series (beginning with the 2d term of
the A-series) by multiplying by

n
S
1
So that the B-series is

X „ X

11 x^ 25 . x^

12 i-:2- 3 1-. 22.32 6 12.22.32.42 ^

As this method of getting the B-series from the A-series
gives the relation of corresponding terms, it makes the settle-
ment of the question of the convergency of the B-series much
easier than Johnson's method. Into the question of con-
vergency I am not entering here, but merely showing how to
get the B-series, whether or not it is a usable solution.

The reason for the above procedure is this: The A's come
each from the preceding by multiplication:
Ai = Ao(l+gi(m-k)+ etc.)
A2=Ai(H-go(m-k)+etc.)

= Ao(l + (gi+g2) (m-k)+etc.)
A,3 = A2(l+g3(m-k)-fetc.)

= Ao(H-(gi + g2 + g3) (m-k)+etc.)
and so on.

n
The coefficient of m — k in An is S g„.

And since, in the expansion, the coefficients of m — k are values
of F'(m), the B-series comes from the A-series by the

n
relation 2 F'(m) using the m factor of Ar-i, as in the fore-
going example.

(2) x(l-x2)4^-f (1-3x2)^- xv=0 (Johnson-lSl)
dx- dx

y = x"> gives m2x"^-i-(m+l)2 x'"+i = 0 (E)

238 The Ohio Journal of Science [Vol. XVI, No. 6,

And we may thus assume an ascending series beginning with
m = 0, or a descending series beginning with m= —1, exponents
differing by 2 in each case.

(1) The ascending series,

00

y = 2 Ar x™+-^
0

gives, by (E),

(m+2r)2 Ar-(m+2r-l)2 A,_i = 0

. (m + 2r-ir. ,.

•■^^" (m+2r)2 ^'-' ^^'

For m = 0, A, = \-,r^ K_, (3) ;
(2r)-

(3) gives the A-series.

Differentiating the m-factor of (2) we have

/(m+2r-l)^\ / 2 \

\^ (m+2r)2 J \(m+2r) (m+2r-l)y

And for m = 0, this is

/(2r-l)^\ / 1 \

V (2ry^ J \r{2r-l)J

And thus the n*'' term of the B-series is derivable from the
(n + l)*'' term of the A-series, beginning with the 2d, by
multiplying by

r = n ^

,.fi?(273Tj W

--' ^'^-i x''+ etc.

By (3) the A-series is

1- ,

y ■'- ' 92 ~'~ 92 42 ' 92 12 [i2

And by (4) the B-series is

il 2 7 P.31 , 37 . P.3151
2 ^ "^ 6 22.42. ^ "^ 30 2-A~.ir. ^ "^

(2) The descending series for the same equation.

(m+l)2 x"^+i — m^ x'"-i = 0, gives,

(m-2r+l)2 x--2^ Ar-(m-2r + 2) x-^-^^-^ Ar-i = 0
(m — 2r-|-2)-
For m = - 1 , Ar = -^Wy^ A,_i (2)
This gives the A-series.

April, 1916] Derived Solutions of Differential Equations 239

Differentiating the m-f actor of (1)

'm-2r+2\'\ / -">

^m-2r+l/ / V(m-2r+l) (m-2r+2)
For m= —1, this is

,^^rj ) \~ 2r (2r - 1)^

And thus the n*'^ term of the B -series is derived from the
(n + 1)*^ term of the A-series, beginning with the 2d, by
multiplying by

^ -2

2

^ (2r - 1) (2r)
The A-series is

12 1- '^^

x-1 (1+ 2^x-2 + ^^x-^+etc.)
And the B -series is

-2x 1 (^ -jjK - + 2^.[jj + -2a)'' +etc.)

(b) Series starting with the same value of m, but not zero.
,dV , dy

X-

^ -3x;^+ (4-x)y = 0

dx2 dx

y = x™ gives (m — 2)^ x"' — x^^+^^O.
.-. Two ascending series, starting with x^,

Form = 2, A,= ,A,_Y-^^ (2);

(2) gives the A-series.
Differentiating the m-f actor of (1),

/ 1 \ / -2 \

\^(m+r-2)7 \m-\-r-2 J
For m = 2, this is

(+) (- ')

The n*'' term of the B-series is derivable from the (n-f 1)'^
term of the A-series by multiplying by

240 The Ohio Journal of Science [Vol. XVI, No. 6,

The A-series is

^" (1+ -p- x+ p^^"+ ^9233^^+ etc.)

And the B -series is

-^x ( — Y + — 10 02 ^ ' fT 12 92 02 ^ "T etc. j

Note — Equations of the sort that give two or more solutions
starting with a value of m different from zero, can be reduced to
the latter sort in two ways. First, by a change of the dependent
variable. If the starting value is x'", set y = x''y. The equation
just considered, if we set y = x-y, becomes

dx- dx
and x™ = y, gives m^ x"""^— x"' = 0

• \- ^ -A
(m-fr)-

Form = 0, A,= A,_J~^\

This gives the A-series.
Differentiating the m-factor,

1 \ / -2 \

(-

(m-|-r)^y Vm+r
becomes, for m = 0,

The B -series is derivable from the A-series by

1 \ ^ /

The resulting two series multiplied by x-, give the required
A-series and B -series.

Or, we might change m — k to n, and deduce the series in
terms of n as heretofore in terms of m. Thus case (b) is always
reducible to case (a).

(c) Series starting with values of m differing by a multiple

of s when

00

V -= :S ArX'"+^'^

0

is the assumed solution.

April, 1916] Derived Solutions of Differential Equations 241

(Compare Johnson, p. 185-9).

xMl+x)^+xg+(l-2x)y = 0

(Compare Johnson, p. 185).

y = x"', gives
(m + 1) (m-2) x-+i + (m2 + l) x- = 0 (1)

And we may select two descending series, beginning with
x-i and x^, with powers differing by unity.

CD

By (1), v= 2 ArX™-"^ gives
1

(m-r) (m-r-3) A,+i+( (m-r)^-+l) Ar = 0 ._

. (m-r)^+l , ...^

••A'-+>- (m_i.) (m-r-3) ^^ ^-'^

For m = 2, this gives,

(2-r)'^+l

(2-r) (r+1)
And this will fail when r = 2
For m= —1, (2) gives

^^+^~ (r+l)(r+4)^^ ^"^^

This gives the A-series, from which, by the method already
used, we can also get the B -series.
Differentiating the m-factor of (2)

/ (m-r)^+l \ / 3(m-r)^+2(m-r)-3 \

\^ (m-r) (m-r-3)J 1^ (m-r) (m-r-3) ( (m-r)2+l)J

When m= —1, this becomes

/ (l+r)^+l \ / 3r^+4r-2 \

1^ (r+1) (r+4)y V (r+1) (r+4) (f^+2r+2)y

Thus the terms of the B -series (except as to those preceding
the A-series) are gotten, the n*^ term of the B-series from
the (n + 1)*'' term of the A-series by multiplying by

5 3r2+4r-2

-^r+i— (ck \ / I i\ -^r

Q (r+1) (r+4) (r2+2r+2)
The A-series is

x-Kl-^x-+-^-^-x-+etc.

242 The Ohio Journal of Science [Vol. XVI, No. 6,

And the B -series is

"^ ^ 4 1.4 "^ ^ 20 1.4 2.5

To get the terms of the B -series preceding the A-series,

_ (m-r) (m-r-3) .^.

^^- (m-r)2+l ^'+^' ^'^ ^^^

Differentiating

(m-r) (m-r-3) . / 3(m-r)''+2(m-r)-3 \

(m-r)2+l) ^^+1 (^ (m-r) (m-r-3) ((m-r)2+l)y

And when m= —1, this is
^^ ^ (1+r) (4+r) .^^ / 3r2+4r-2

^r— „2 I o„ I o -"-r+l

r2+2r+2 '+^\^(H-r) (4-fr) (r2+2r+2)y

.,_, f (l + r)(4 + r) 3r^ + 4r-2 )

•• ^^-^^+1 1 r2+2r+2 {r''+2v^2Y ^^^+1^+ ^^^j

.-. A_i = Ao (0+3 (m+1)

A_2 = A_i (1+ki (m+l)+ etc.
= Ao (0+3 (m+l)+ etc.)

A_3= A_2 (| +k2 (m+l)+ etc.)

= Ao(0+^(m+l)+etc.)

A_4 = A_3 (O+kg (m+l)+etc.)
= Ao(0+0(m+l);

and all subsequent terms vanish as to m + 1.
.-. terms to be added are

Bo(3+3x+^x2)
o

Vanishing of the first term in A_i prevents using the pro-
cedure used heretofore, since in this case a summation no
longer holds.

(2) 4x(l-x)|^-4^-^-y = 0

dx^ dx

y = X™ gives

4m (m- 2) x--i- (2m- 1)^ x'" = 0

/. series start with x" and x-; exponents of powers differ
by unity.

April, 1916] Derived Solutions of D iff ere?itial Equations 243

_ (2(m+r)-3)^ "

^^~4(m+r) (m+r-2)^'-^ '^^''

For m = 0, the series would fail for r = 2.
For m = 2

_ (2r+l)^ ,

^^"2r.2(r+l)^'-^ ^^^

This gives the A-series.
Differentiating (1)

_ (2(m+r)-3)^ 2(m-r)-6

4(m+r) (m+r-2) '"Hm+r) (m+r-2) (2(m+r)-3) ^

And when m = 2, this is

_ (2r-l)-^ . 2(r-l)

^ 2r.2(r+2)^-' r(r+2) (2r+l)

The B -series derivable from the A-series is gotten thus:
The n*^ term of the B-series from the (n + 1)*'' term of the
A-series by multiplying by

S 2(r-l)

^ r(r+2) (2r+l)

And the terms of the B-series preceding the A-series
come from

_ /2r^2(r+2)__8(r-R)_ \

'-' ^^'\ (2r+l) (2r+l)3 ^ ^^ ^

.-. A_: = Ao (0+8(m-2))
A_2 = A_i(-4-16(m-2) )
= Ao(0-32(m-2) )
A_3 = A_2(0+k(m-2)
= Ao(0 + 0(m-2) )

.-. the terms are

Bo(-32 + 8x)

THE ELECTRICAL CONDUCTIVITY OF INDIUM AND

THALLIUM.

Alpheus W. Smith.

The behavior of the electrical conductivity of metals when
the metal passes from the solid to the liquid condition is of
increasing interest and importance in the formation of an
electron theory of metallic conduction. Except for the excellent
work of Northrup,* little systematic work has been done in this
field. It is the purpose of this short paper to give some results
obtained for indium and thallium.

In order to make possible observations on the metal in the
liquid as well as in the solid condition, the metal to be studied
was introduced into a glass tube one end of which was closed.
Four platinum wires were sealed into this tube so that they
were at right angles to its axis. Two of these wires served as
potential and two as current electrodes in the ordinary Thomson
double bridge method of comparing low resistances. This
glass tube was about 3 mm. in internal diameter and the dis-
tance between the potential electrodes was about 2 cm. A
sufficient quantity of the metal was introduced to fill the tube
above the platinum electrode farthest from the closed end.
The air was exhausted from the tube and it was then sealed off
to prevent the oxidation of the metal on fusion. After fusion
the metal was allowed to cool slowly from the liquid to the
solid state.

In order to secure the necessary temperatures for these
observations a cylindrical electrical furnace wound with
nichrome wire was used, except for room temperature and the
temperature of melting ice. The temperatures were determined
by means of a mercury in glass thermometer which was filled
with nitrogen. The observations on the resistances were made
in the usual way with a Thomson double bridge which was
obtained from Wolff. The standard low resistance was a coil
had a resistance of 0.001 ohm at 20 C. The indium and
thallium were obtained from Merck & Co. No chemical anal-
ysis was made of them and no attempt to further purify them.

* Jour. Franklin Inst. 175, pp. 153-161 (1913).

244

April, 1916] Conductivity of Indium and Thallium

245

In order to calculate the specific resistance of the indium the
specific resistance at 0° C. was taken as 8.37 x 10"'^ ohms. This
is the value found by Erhardj who made his observations on
indium in the form of wires. Taking this value as known the
value of the specific resistance for any other temperature could
be at once calculated. In the case of thallium the value by
Dewar and Flemingf was assumed to be correct. These

^

Vo

X

3—

•. O'

^

i— '

5

-e-

C5 —

8

(^

^

r

(,

■

H'"^

'^

^

■T

■) 1

-£

•jkyO-

--^

%A

^''

2/ <:

e^

t--^

^

(

y^

3-2

24-

u

0.8

100"

zoo°
Figure 1

300

^00 T

observers found the specific resistance of thallium to be 17.60
X lO"*' ohm at 0° C. From this value the other values for the
specific resistance were calculated.

The results of these observations have been given in Table I
and have also been plotted in the accompanying figure 1 in which
the ordinates are the specific resistances in ohms and the
abscissae are the temperatures. Some of the observations were
made with increasing and some with decreasing temperature.
In each of these cases is seen the characteristic discontinuity in
the curve at the melting point of the metal. In each of these

t Erhard, W. A., 14 p. 504 (1881).

JDewar and Fleming, Phil. Mag. (o) 36, p. 271 (1893).

246

The Ohio Journal of Science [Vol. XVI, No. 6,

two metals the resistance in the solid as well as in the liquid
state is nearly a linear function of the temperature. The rate
at which the resistance increases with the temperature is less in
the liquid than in the solid state.

TABLE I.

Indium

Thallium

Temp.

pxlOs

Temp.

pxl06

0°

8.37

0°

17.60

24.1

9.27

28.4

19.59

34.7

9.62

41.8

21.11

60.2

10.85

45.1

21.31

80.4

11.48

83.0

24.46

86.4

11.98

84.7

24.62

121.4

13.09

133.2

28.72

141.8

14.56

135.0

29.09

142.7

14.63

197.5

35.10

154.0

29.10

198.0

35.14

156.8

29.28

254.0

40.16

166.8

29.66

258.2

40.22

181.5

30.11

301.7

83.38

182.8

30.13

302.5

83.60

198.5

30.84

305.5

83.61

220.0

31.87

309.0

83.89

230.0

32.29

321.0

84..32

261.0

33.31

347.0

84.84

280.2

34.87

356.0
367.4
382.0
401.5
422.0

85.35
85.34
85.95
86.78
87.54

TABLE II.

Met.\l

1
Ro

X 103

Rl/Rs

Indium

Thallium

5.24
5.27

3.98
1.95

2.00
1.90

Table II gives the temperature coefficient of the resistance
of thallium and indium before and after melting. The second
column gives this coefficient before melting; the third column,
after melting. In the last column of this table is the ratio of
the resistance before and after fusion. Within the error of
observation this ratio is 2.00 for indium and 1.90 for thallium.

April, 1916] News and Notes 247

The temperature coefficients of the resistance here recorded are
somewhat larger than those found by Erhard for indium and by
Dewar and Fleming for thaUium. The former working between
• — 5.4° C. and 96° C. gives for the temperature coefficient of
indium 4.77 x 10~^ the latter working between 0° and 100°
gives for the temperature coefficient of thallium 3.98 x 10~^
These discrepancies are probably due to impurities and to
mechanical treatment of the specimens.

I wish to express my thanks to the Rumford Committee
which bore part of the expense of this investigation.

Physical Laboratory, Ohio State University.

NEWS AND NOTES.

The Ohio Academy of Science. The Annual Meeting of
the Ohio Academy of Science was held on April 21st and 22d
at the Ohio State University. The general meetings were
held in the Botany-Zoology Building. This is the first meeting
after the adoption of the new plan to meet in the spring.

The Lake Laboratory. Plans for a successful session of
the Lake Laboratory at Cedar Point next summer are rapidly
maturing. It has been unofficially announced that a number
of improvements to the building and to the sanitary arrange-
ments will probably be made which will increase the efficiency
of the laboratory and will also make for greater comfort in the
living conditions.

The bulletin for 1916 has recently been issued. The session
will begin on June 19 and will continue until July 28. As usual
those desiring to spend a longer time at the laboratory are at
liberty to do so. Director Osborn will be away on leave of
absence this summer. The acting director will be Dr. F. H.
Krecker of the Department of Zoology and Entomology at
Ohio State University. Other changes on the staff include the
appointment of Professor Schaffner of the Department of
Botany at Ohio State University, and of Prof. Z. P. Metcalf, of
North CaroHna A. and M. College. Prof. Metcalf will conduct

248 The Ohio Journal of Science [Vol. XVI, No. 6,

the courses in Entomology and Ornithology. Among the
changes to be noted in the curriculum is the increased attention
which can be given to botany because of the presence of an
additional botanist on the staff. Prof. Schaffner will have-
charge of Plant Ecology and Advanced Plant Morphology. Prof.
Fullmer, of Bald win- Walace, will direct the work in Systematic
Botany and special work on the Algae of the Cedar Point region.
Dr. Krecker will enlarge the scope of the work offered in
Aquatic Zoology which is presented from the ecological stand-
point. Prof. Williams, of Miami University, will conduct the
Advanced Invertebrate Morphology and the Vertebrate Anat-
omy.

In all the courses a special point is made of giving students
as much contact with field conditions as possible. The Cedar
Point region is fortunate in being one of the few inland points
offering a wide range of conditions. The outdoor side of
biological subjects is so important and is so slightly accessible
to students during the winter that opportunities such as those
offered at the Lake Laboratory are invaluable. It should be
mentioned in this connection that the work done at the Lab-
oratory is accepted for credit in most institutions. The facil-
ities of the Laboratory are offered to both students and inde-
pendent investigators and either Director Osborn or Acting
Director Krecker will be glad to give information regarding
necessary arrangements to any who may be interested. And of
course early inquiries will be of advantage to everyone concerned.

Date of Publication April 24, 1916.

THE

Ohio Journal of Science

PUBLISHED BY THE

Ohio Statk University Scientific Society

Volume XVI M A Y , 1 9 1 6 No. 7

TABIvE OF CONTENTS
Wells — The Comparative Morphology of the Zoocecidia of Celtis occidentalis 249

CoGAN — Morphological Studies of the Superfamily Jassoidea 299

Drake— A New Tingid from Tennessee 326

THE COMPARATIVE MORPHOLOGY OF THE
ZOOCECIDIA OF CELTIS OCCIDENTALIS.*

Bertram W. Wells.

The purpose of the present paper is three-fold:

1. To present a survey of the known insect and mite
galls of Celtis occidentalis L.

2. To elucidate the histology of the normal gall bearing
parts of the hackberry and that of the galls.

3. To study comparatively the structures treated, pointing
out any significant conclusions and generalizations that may
be attained in such a study.

During the course of personally collecting nearly five hundred
types of zoocecidia, the author early discovered that the
hackberry and its galls would afford a favorable combination
with which to prosecute some anatomical work as outlined
above. Four orders of cecidozoons are represented on this
species of tree, causing seventeen known kinds of galls,
of which sixteen are described in this paper. These orders
do not include the hymenoptera whose galls are better known
than those of the other orders. The histology of but one of
the galls here presented, has been described previously. Since
only one species of Celtis occurs in the regions (Ohio and
Kansas) from which the material was obtained, no problems
of correlation with various host plant species were encountered.

*Contribution from the Department of Botany, Ohio vState University, No. 95.
This paper is the partial fulfillment of the requirements for the degree of master
of arts.

249

250 The Ohio Journal of Science [Vol. XVI, No. 7,

Neither Celtis occidentalis L. nor any of the known insects
forming galls on it, are reported from Europe. Houard ([11],
Vol. I, p. 367) mentions two mite and two aphid galls occurring
on Celtis australis L. and one aphid gall on C. cretica L.

Most of the gall material and the pieces of the normal leaf
and petiole were collected in the latter part of the summer
to insure maturity, and were satisfactorily embedded in paraffine
and aniline safranin and gentian violet were used in staining
the serial sections. The one year old stem material was taken
in mid- winter. The studies of the witches-broom, the psyllid
stem galls, the lepidopterous stem gall and the structure of the
normal stem were made from sliding microtome sections of
alcohol hardened material. These were treated with iodine
and mounted in glycerine, a method used by Brown and shown
by him (not yet published) to give greater satisfaction in the
case of woody structures, than the longer methods of embedding
and staining. All drawings, histological in character, were
made with the aid of a camera lucida or projection lantern.

About one-third of the work was done while the writer was on
the teaching staff of the Botanical Department of the Kansas
State Agricultural College, and he desires to express his apprecia-
tion of the kindly interest in the work on the part of Prof. H. F.
Roberts and the other members of that department.

The remaining two-thirds of the work was completed in the
Botanical Department of the Ohio State University under the
direction of Prof. J. H. Schaffner, to whom the writer is indebted
for many helpful suggestions, particularly in regard to the
theoretical aspect of the subject.

It gives the author especial pleasure to acknowledge the
very valuable assistance rendered by Mr. Forest B. H. Brown,
of the Ohio State University botanical staff. His excellent
grasp of plant anatomy has made possible a source of informa-
tion and inspiration, upon which the writer has drawn heavily.

To Prof. Herbert Osborn, of the Ohio State University is
due the hearty thanks of the writer for the loan of entomological
literature.

Much work has been done on gall anatomy in Europe, but
little as yet in America. The great majority of all the anatom-
ical papers heretofore published have been general in character,
dealing with many kinds of galls on many kinds of plants.

May, 1916] Morphology of the Zoocecidia of Celtis 251

The present paper is perhaps unique in that it deals com-
paratively with practically all of the galls on one kind of plant,
and with the normal tissues of that plant. The presentation of
the histology of the normal plant parts will be given first.

HISTOLOGY OF THE NORMAL PLANT PARTS.

The discussion of the histology of the normal plant parts will
be followed by the descriptions of the galls arranged under the
proper insect order and family name.

The elucidation of the normal histology was deemed impor-
tant, for it is necessary to have clearly in mind the results
of normal differentiation to adequately understand to what
extent the galls have deviated in their specific structure, from
the normal plant characters.

The Leaf. (PI. XII, Fig. C). The upper epidermal cells
are comparatively large and bear externally a thick cutinous
layer. Large cystolith cells (cys.) break the continuity of the
typical epidermal elements. The expanded internal part of
the cystolith shows the presence of the calcium carbonate
in it by staining very lightly if at all, while the stalk and the
round external knob takes the aniline safranin with avidity.

The palisade zone consists of two layers of cells, the inner
being much less prominent and in places merging with the
elements of the spongy layer so as to break its continuity.
The spongy layer is relatively compact.

The fibro-vascular bundles possess a more or less definite
bundle sheath, composed of highly elongated cells with evenly
thickened walls. These are especially well developed above
and below the bundle (PL XII, Fig. C, a). The xylem elements
are the characteristic tortuous tracheides of the spiral type.
The phloem cells are as in leaves generally of the thin-walled,
more or less elongate, sub-cylindric form. The end walls often
slant at an appreciable angle.

The under epidermis consists of cells somewhat smaller than
those of the upper protective layer. The outer walls are
sufficiently thin to permit the protoplasts to bulge them out-
ward. The stomatal cells are minute, the pair being inter-
calated between the larger epidermal elements at their bases.

The Petiole. The petiole as seen in transverse section,
shows the typical asymmetric orientation of the fibro-vascular
bundles, which, taken collectively, form a crescent-shaped

252 The Ohio Journal of Science [Vol. XVI, No. 7,

area, lying nearer to the stem side of the petiole than the outer
side. A segment from the middle of this region is shown in
detail (PI. XVI, Fig. D), extending from the epidermis on the
side away from the stem axis, to a point on the inner side of
one of the bundles.

The cortical cells and the epidermal cells show definitely
thickened walls; a non-lignified type of thickening, however.
These walls possess simple pits (not numerous). Scattered
bast fibres are found in the inner cortical region, whose walls are
not as thick, however, as those of the stem.

The phloem and xylem show no special characteristics.
Tracheae and tracheids make up the body of the xylem, the
tracheids being larger than many of those found in the stem
and those found in the leaf.

The Stem. Figs A and B, PI. XII, show the transverse and
longitudinal, radial sections, respectively, of the one year old
stem in winter condition. The cork layer is of the common
type. The phelloderm is one cell layer thick. True collen-
chyma is but weakly developed, consisting when found in a
favorable section, of but a single layer of cells of the outer
cortex, with thicker walls than those beneath it. Since the
cortex cells inward as far as the scleride and crystal "sac"
layer, have definitely thickened walls, the differentiation
between them and the collenchyma is ill defined. These
cellulose-thickened walls show minute inter-cellular spaces
between, but the simple pits which doubtless are present in
them could not be definitely demonstrated as were those of the
petiole cortex.

On its inner side the zone of cells just described (primary
cortex) is sharply delimited by a layer two or three cells thick
(typically) containing two kinds of elements ; sub-isodiametrical
sclerides or stone cells and cuboidal to slightly tangentionally
flattened cells, each containing a monoclinic crystal of calcium
oxalate. See Figures labeled with abbreviations. This scleride-
containing cylinder of tissue is of especial interest because
similar types of sclerenchymatous elements occur massed in
various forms in most of the galls to be described hereafter.
The region of the nodes, (particularly best developed in the
cortex of the "angle") shows these two kinds of elements
developed in sub-spherical masses.

May, 1916] Morphology of the Zoocecidia of Celtis 253

The bast fibre cylinder is differentiated directly next to the
layer just described. Within the bast fibre zone a layer of small
celled parenchyma forms a transition tissue to the phloem which
latter is typical and will not be discussed in detail, other than to
state that the outer phloem parenchyma as well as that of the
medullary rays in the phloem region, contain numerous sphaer-
raphides (calcium oxalate).

The cambium consists of the typical, tangentionally flattened
brick-shaped cells, massed three to six cells deep before exhibit-
ing differentiation.

In the xylem region wood fibres and tracheids of small
diameter predominate. The tracheae of both primary and
secondary xylem are of the ordinary types. It might be noted
in passing that the innermost tracheal element of the secondary
xylem co-ordinates perfectly with the adjoining vessel of the
primary xylem in the development of the transversely elongated
bordered pits, which relate the two. The medullary ray cells in
the region of the wood, shows the typical sclerenchymatized
condition, with the walls containing numerous simple pits
extending to the middle lamella.

The tracheids, whose distribution in the stem is variable are
of particular interest in connection with this study, because of
the fact that it is only this kind of xylem element which is
found in the appendicular hemipterous and dipterous galls.
In the stem they are of extremely fine structure, particularly
those formed near the end of the season's growth, possessing
spiral and split-spiral thickenings of very minute size.

Inwardly the primary xylem is bordered by some cylindrical
elements with slightly thickened walls forming a transition
tissue to the storage or "differentiated" pith, which forms the
periphery of the medullary cylinder. The cells of this storage
tissue possess as usual large numbers of simple pits.

The large celled pith is of interest, since an exactly similar
type of parenchymatous tissue is found in many of the galls.

Older stems were examined showing the products of sec-
ondary growth, but nothing new or of a type which possessed
additional significance relative to the problem in hand, was
found. All of the galls on the hackberry are developed from
the meristem functional in primary growth, the insects in all
cases being unable to gain access to meristematic elements
after the first cork layer has formed.

254 The Ohio Journal of Science [Vol. XVI, No. 7,

Callus was not grown and examined, since from much
previous work it is evident that this type of homogeneous
tissue, approximately the same for all plants, has no significance
in relation to the gall problem.

Wound wood, however, was investigated, but nothing
different was found from similar kinds of tissue reported in
other trees. In none of the galls studied was anything found
approximating in the slightest degree the condition of things
characterizing wound wood. Such may be the case, however,
as is shown by Stewart (31) in the gall of Andricus punctatus
Bass, on the oak.

DESCRIPTION OF ZOOCECIDIA.

Thomas (32) has defined a gall as "a variation in the form
of plants caused by a parasite." This definition, though
rather widely accepted, is too indefinite and does not delimit
certain irregular conditions in plants brought about through
predaceous insects and intracellular fungi, conditions which
are never associated with the word cecidium or gall. In the
author's work on zoocecidia (nematode, mite and insect galls)
he has found it possible to adhere to the following definition
for zoocecidium: An hypertrophy (abnormal enlargement
of single cells) or hyperplasia (abnormal proliferation of cells)
of plant cells causally related to certain parasitic animals.
Both hypertrophy and hyperplasia may go on in the same gall.
The only cases which this definition does not cover are those
in which the normal tissue suffers differentiation inhibition
without evident hyperplasia or hypertrophy. These cases are
extremely rare. The xylem region of gall 1, described in the
present paper is an instance of this kind, but as the cortex
suffers marked hyperplasia this case is not a true example.
Cases of this sort in which the number and size of the elements
is not increased, only their qualities have changed, are included
by Kiister (15) under "Metaplasias."

Kiister (15, IG) in his Pathologische Pflanzenanatomie
has given phytopathology an excellent classification of cecidia
in general. All of the galls described in the present paper fall
under his "Heteroplastic Tissues," that sub-division of hyper-
plasias which shows "definite quantitative increase of an
organ, in which by abnormal cell division, tissues are produced,
the single elements of which do not resemble normal ones.

May, 1916] Morphology of the Zoocecidia of Celtis 255

If the tissue of the heteroplastically changed organs and parts
of organs be compared with corresponding normal tissues,
differences will be found in more than one connection; the
abnormal tissues vary from normal ones in regard to size of
the single elements, as well as to the degree and kind of
differentiation."

In the mind of the writer, the "degree and kind of dif-
ferentiation" of tissues is the most significant with particular
reference to the form assumed by the heteroplastic tissues
as opposed to the forms of similar tissues in the normal parts.

Heteroplasmas, Kiister divides into two sub-divisions,
" Kataplasmas (differentiation not widely different from the
normal) and " Prosoplasmas " (differentiation definitely and
specifically different from the normal). The acarinous and
lepidopterous galls (one each) to be described hereafter fall
under the first, while the hemipterous and dipterous forms are
all excellent examples of the second.

In the description of the galls, the taxonomic characters will
be presented first, followed by the discussion of the histology.

In conformance with a previous paper (Wells [33]) the new
galls described are not named, but given a list number. As
pointed out in that paper it is essentially unscientific to name
an insect with only the gall at hand. No entomologist would
feel justified in creating a species on the characters of a
puparium or coccoon, for such a structure embraces but a
small part of the total number of characters to be considered.
Only the paleo-entomologist should have the privilege of
dealing in fragments. While it can be shown that the specificity
of the galls is related to the specificity of the adult insects, this
relation is not a causal one, but is merely a relation established
through the fact that both gall and adult insect have a common
specific origin in the larva. If the entomologist is to properly
describe his unit (species) he should have all of the differentia-
tion products coming out at the end of the insect's ontogeny.
Too frequently, the entomologist has ignored the gall as a
"deformation," when it is often as specific as the antennas in
its form and structure characters.

256 The Ohio Journal of Science [Vol. XVI, No. 7,

KEY TO GALLS OF CELTIS OCCIDENTALIS.

1. Twig galls; twigs massed and showing enlargement of bases, witches broom.

Eriophyes sp. (1).
L Twig galls; aborted lateral twigs, isolated not aggregated, Lepidopterous

gall, (2).
1. Twig galls; simple low, ovoid swellings on sides of twigs, Pachypsylla sp., (4).
1. Bud gall; an abnormal enlargement of bud, Pachypsylla gemma, (5).

1. Galls on leaves and twigs, if on latter very different from foregoing. 2.

2. Gall of petiole, pear-shaped, large, involving entire petiole, Pachypsylla

venusta, (7).
2. Leaf gall, blister-like, projecting but slightly from either side of leaf,
Pachypsylla vesiculuin, (3).

2. Leaf and twig galls, projecting prominently; definite appendicular structures. 3.

3. Leaf blade only; definite concavity on side of blade opposite gall, Pachypsylla

mamma, (6).

3. Leaf blade, petiole and twig galls, on blade never showing concavity on side

opposite the gall; itonid galls. 4.

4. Galls definitely conic; body of gall contracted distally. 5.

4. Galls definitely obconic; body of gall contracted proximally. 8.

4. Galls definitely globular, Cecidomyia sp., (14.)

4. Galls otherwise. 9.

5. Galls with ends attenuate, 6.

5. Galls with ends truncate (small nipple in center) 7.

6. Galls small, 2-3 mm. long, base not prominently expanded, Cecidomyia sp., (11).

6. Galls larger, 3-5 mm. long, base prominently expanded, Cecidomyia tingui-

cola, (8).

7. Galls coarsely pubescent; distal half rather sharply constricted from basal,

Cecidomyia sp., (13).
7. Galls smooth; distal half not constricted from basal half; stoutly conic,
Cecidomyia sp., (12).

7. Galls smooth, larval chamber falls from the socket-like base. Cecidomyia sp.

(16).

8. Gall sub-balloon-shape; basal half definitely constricted from distal expanded

half, coarsely pubescent, Phytophaga celtiphyllia, (9).

8. Gall top-shaped; basal half not definitely constricted from distal half, finely

pubescent, Phytophaga well si, (10).

9. Gall greatly flattened with central nipple; more or less prominent vertical,

peripheral ridges present. (See end of introduction to the descriptions of the
Itonididse galls).

9. Galls relatively large, with very prominent, vertical, wing-like ridges pro-
jecting from the body of the gall, Cecidomyia sp., (15).

9. Galls generally in masses, larval chamber eventually loosening and dropping
from the loasal parts, Cecidomyia sp., (16).

Fam. Eriophyid^. (Ord. Acarinae).

This family includes the vast majority of the gall-forming
mites. The galls are of simple types, though exhibiting great
diversity. Most of the mite cecidozoons affecting the American
flora, are undescribed, a condition related to the fact of their
minute size and soft body, characters which demand a special
technique to handle them. The majority of gall makers are
members of the genus Eriophyes.

1. Eriophyes sp. This gall, a typical witches-broom,
(PI. XIX, Fig. 1) represents a more or less serious disturbance

May, 1916] Morphology of the Zoocecidia of Celtis 257

of growth at the nodes. An excessive number (2 or 3 generally)
of abnormal (wood reduced, pith increased) branches are
produced from the same bud, followed by the development
of an indefinite number of buds, all closely sessile in a mass at
the node between the "gaU" branches (PL XIII, Fig. 1).
The subsequent infection of the basal buds of the new branches,
the buds nearest to the original node attacked, accounts in
great part for the characteristic irregular massing of the
branches. If a young "broom" be stripped of its bark, (PL
XIII, Fig. la), this relation of the primary and secondary
branches is made evident. Often, however, in later years,
buds located at the base of the primary "gall" branches will
develop a shoot. After a number of years the mass of branches
becomes so large as to be very conspicuous and unsightly.
The author has investigated new branches growing on old
galls without finding any mites. It seems probable that the
condition of things grows worse after the primary infection,
whether or not the mites are present.

The gall proper is altogether confined to the nodes affected,
in which region two prominent facts stand out in relation to the
histology of the parts affected: (1) The bases of the gall
branches have suffered an inhibition of their differentiation;
(2) The cortex shows definite hyperplasia. These facts are
shown in PL XIII, Fig. Ic, which illustrates the longitudinal
section of the part indicated at c, in Fig. la, which is a longi-
tudinal, median section through a primary "gall" branch and
the normal twig, from which it has grown out. The condition
of the xylem is an extreme case of differentiation interference.
Note the medullary ray cells are not very unHke those bordering
it, cells which should have become wood fibres and tracheids,
but which remain iso-diametrical, possessing simple pits
scattered in the somewhat thickened walls. The co-ordination
of the tracheae, which do form, with the cells adjoining them
by means of bordered pits, is not interfered with (PL XIII,
Fig. Id).

Different branch bases show a wide variation in the degree
with which normal differentiation has been checked. The
extreme cases are almost uniformly composed of iso-diametric,
simple-pitted cells, the thickening of the cell waUs characterizing
the pith region with as much intensity as the xylem. The least
affected cases will show numerous vessels and tracheids, but few

258 The Ohio Journal of Science [Vol. XVI, No. 7,

if any wood fibres. This variation is undoubtedly related to
the degree of differentiation attained before the advent of the
mites in the spring growth period.

The hyperplasia of the cortex of the branch base is a con-
stant character. The stone cells are found aggregated into
sub-spherical masses, a condition also true of the crystal
bearing cells. These masses were much larger and more num-
erous than those found in the normal nodes, and often are
found in juxtaposition (PI. XIII, Fig. 1 c).

The cork developes a greater thickness than normally, but
is not sharply defined from the primary cortical parenchyma.
The elements of this latter tissue do not thicken their walls.

The above study is corroborative of Kiister's (15) dictum
that all witches-brooms, whether mite or fungus induced,
exhibit an essentially undifferentiated condition.

Kellerman and Swingle (12, 13) have associated a fungus
(Sphaerotheca phytoptophila Kell. and Sw.) with this gall.
No mycelium was seen in the affected tissues; indeed none
would be expected belonging to the fungus named, since its
position among the Erysiphaceas would indicate it to be wholly
superficial, the haustoria only affecting epidermal cells. Other
well known witches-brooms, particularly those of Europe,
have been shown to be caused by mites only. One on Syringa
is especially striking. See Abromeit (1). There can be no
doubt that the kataplasma under discussion, is wholly induced
through the agency of acarinous organisms.

Lepidoptera.

Practically all of the lepidopterous galls are of the stem
kataplasma type. The larva works its way into the center of
the stem and from that vantage point brings about important
deviations from the normal sequence of events in the growth of
the tissue. This is in marked contrast to the mite induced galls,
for the mites occupy at first at least, an external position.
Stem mite galls are known, however, which at length enclose
the animals.

2. Lepidopteron (species undetermined). This gall, (PI.
XIX, Fig. 2) is an aborted shoot from a lateral bud, developing
very rapidly in the early spring, reaching its full size (in Kansas)
toward the end of April. 1^2 ~ 3 cm. long, 4-6 mm. wide.
The nodes near the end of the gall bear small leaves which die

May, 1916] Morphology of the Zoocecidia of Celtis 25&

early. Affected stems either smooth or pubescent. The larva
finishes feeding on the central part of the galled twig and leaves
the structure during the early part of May. It always eats out
a circular hole near the base to make its exit. (PI. XIII, Fig. 2 a).
The gall soon after turns brown and drops from the parent branch.

Patton (26) has described a "hollow, elongate, twig swelling"
from which he states cecidomyidous flies emerged "about the
middle of June." From his brief description it is impossible
to state whether his gall is the same as the one here described.
The flies noted might have been parasitic on the lepidopteron.

Riley reports a tortricid, Proteoteras sesculana Riley,
occurring on the hackberry. No mention of any gall is made,
however, in connection with this tree, other than that the larvae
were found "on short twigs." On the buckeye and maple it
"bores in the terminal green twigs, producing a swelling or
pseudo-gall." (See Am. Nat. cit. below). This may be the
insect concerned in the production of the lepidopterous gall
herewith described, but from this mere suggestion of its gall
forming habit, it is impossible to be certain.

Riley, Trans. St. Louis Acad. 4:321-322. 1882.

Rilev, Am. Nat. 16:913-914. 1882.

Riley, oth Report U. S. Ent. Comm. p. 609. 1890.

When studied histologically this gall is seen to be an
excellent type of kataplasma (PI. XIII, Fig. 2d). Sections of
the normal and galled twigs are contrasted in 2b and 2c. The
normal stem has suffered serious inhibition of its differentiation
associated with marked hyperplasia. The xylem consists of
but few primary and secondary vessels. The cambium is
practically obliterated in the general mass of parenchyma
formed. The bast elements never attain their ordinary heavy
walls. The layer of stone cells with its accompanying crystal
bearing elements does not appear at all. This study was made
from material which had already begun to die back at the distal
end, so that the condition found is not any stage of incomplete
normal differentiation.

Fam. PsYLLiD.^. (Ord. Hemiptera).
The psyllidse among hemipterous gall makers take third
place, the aphididge and coccidce surpassing them in number of
genera and species. Kiister (17) reports seven genera from
Europe. There are three known in America, the genera
Livia, Trioza and Pachypsylla, which latter is confined in its-
gall forming habits altogether to the hackberry.

260 The Ohio Journal of Science [Vol. XVI, No. 7,

Five psyllid galls belonging to the genus Pachypsylla are
herewith presented. The author concurs with Crawford (4,
p. Ill) in his monograph of the Psyllidae, when he asserts that
the following species of Pachypsylla erected by Riley (28) in
the Fifth Rep't of the U. S. Ent. Comm., viz.: P. astericus,
umbilicus, pubescens, globulus and curcurbita and P. rohweri
Ckll, are "only variations of the species of P. mama, since the
insects are said to be similar and the differences in the galls are
not great." These species evidently represent intermediate
forms between P. mama Riley and P. vesiculum Riley, though
they are much closer to the former than the latter. The
writer has noted the wide variation obtaining among the P.
mama forms. The above named species will not be included in
this paper, since their validity is rightly doubted. There are
three species known other than those whose galls are dealt
with in this paper, viz. : P. dubia, pallida and inteneris, but no
galls are described with them. They are all said to be closely
related to P. gemma Riley and may ultimately prove to be
varieties of that species.

In the following studies diagrammatic presentation is
resorted to in the elucidation of entire gall sections. Lignified
tissue entering into the formation of the protective layers
is shown by cross-hatching; simple stippling indicates paren-
chyma and the vascular bundles are outlined. The portions
of the sections furnishing the diagrams used in detailed studies
are outlined on the diagram.

3. Pachypsylla vesiculum Riley. This, the simplest of the
psyllid galls, is a small (2-3 mm. dia.) monothalamous "blister"
gall of the intervenal tissue, commonly found close to the
principal veins of the leaf. They are apt to occur in great
numbers. More or less evenly convex above; a small, rounded
central papilla can be determined below. The galls, both
above and below, become lighter in color than the normal leaf,
though very green when young. Easily evident from the
latter part of May on through the summer.

Riley, Sth Report U. S. Ent. Comm. p. 618. 1890.

The section of the gall in its position near a principal vein, is
shown in PI. XIII, Fig. 3. The convex zones of sclerenchy-
matized cells are very definite, extending over either side of the
chamber, forming the protective envelope; protective in the

May, 1916] Morphology of the Zoocecidia of Celtis 261

sense that it has a real function in preserving the deHcate
nymph within from mechanical injury. At x, is observed the
primary cone (now flattened) which grew up and around the
young nymph and at y, the rounded papilla, which represents
the original downward evagination, which lowered the larva to
the center of the leaf, making possible the comparatively
greater hyperplasia of the central mesophyll.

The histology of the left part of the section shown in the
diagram is delineated in PI. XIII, Fig. 3a. The epidermis is
not widely aberrant from the normal, though the cystolith cell
has been partially aborted, which was uniformly the case when
these occurred over the affected mesophyll. The upper
palisade layer has maintained its integrity and the lower part
of the spongy layer, nearly so, for stomata are present leading
into small air spaces. The central mesophyll has, it is evident,
been the tissue concerned in developing the "blister." It is of
some interest to note that the thickness of the blister has been
attained, not by a striking difference in the number of cells,
comparing the periphery with the tissue near the chamber, but
by the increase in size of the hyperplasia cells, the number of
cells at the periphery and near the chamber being approximately
the same. The protective layer appears broken, though if the
adjoining sections are taken into account, the layer is found
to be continuous in the fashion of a sieve. The sharpness with
which the lignified cells are delimited from the outermost layers
on both sides of the leaf is a prominent fact. The smaller
veins of the leaf which traverse the region affected show very
little if any modification. They pass between the lower
epidermis and the protective layer. They do not, however,
develop sheath tissue on the upper side, the side next the
sclerenchyma layer.

4. Pachypsylla sp. (gemma? See next). PI. XIX, Fig. 3.

This gall is a lateral, oval swelling of the stem, generally
found near or involving the nodal region. 5-7 mm. long,
2^-33^2 mm. wide. Color and surface texture that of the
normal bark. Predominately monothalamous ; confluent cases
occur forming a two-chambered and even a three-chambered
gall. Very common on the terminal twigs of the hackberry.
Remnants of old galls can be made out on stems 5-10 years old.

262 The Ohio Journal of Science [Vol. XVI, No. 7,

The galls are commonly torn open by birds to obtain the soft
insects within, which spend the winter in the galls. One of
these nymphs is shown on the gall (PI. XIX, Fig. 3).

It is not definitely known whether the imagoes from this
gall and those from the next, P. gemma, are identical. The
nymphs appear to be identical. The galls, however, are dis-
tinct, a difference, however, which may be referable to the
plant part affected rather than to any specific behavior on the
part of the insects respectively. This matter will be explained
after P. gemma has been described.

This gall started in a similar manner to that of P. vesiculum,
by the larva inducing a cone of tissue to grow over it, burying
it in the superficial layer of the young stem. This minute cone
early becomes obliterated.

A transverse section of the stem and its gall is shown in
PI. XIV, Fig. 4a. The influence of the insect in modifying the
growth and differentiation of the embryonic cortical tissue, has
extended nearly around the stem. The outer protective layer
is much heavier and better defined than the inner. Two
prominent elongate, thick plates of mechanical tissue extend
from the broken inner sclerenchyma zone, outward toward
the attenuate edges of the outer mechanical layer; a definite
adaption to insure rigidity. The soft interior tissue bounding
the larval chamber is made up of cambium-like parenchyma,
the cells being very regularly oriented in radial row^s. This
constitutes the nutritive layer (PI. XIV, Fig. 4c).

Fig. 4b shows in detail a part taken at b. Fig. 4a. The outer-
most sclerenchyma elements are true sclerides and have numer-
ous crystal containing cells scattered among them. The cork
enveloping the gall is normal, except that the number of cell
layers is not as numerous as in the unaffected stem. The
epidermis and often the hypodermal layer with it, is found
broken and peeling off, w^hile that on the stem opposite the gall
is intact.

A much magnified detail (Fig. 4d) has been made from the
region d in Fig. 4 a, PI. XIV, to show the origin of the tissue
which has formed the bulk of the gall. At this point of transi-
tion between the hyperplasia tissue and the normal, it is at once
seen that the phellogen layer has furnished the meristematic
tissue, which has been directed to such unusual development,
for the new tissue is strikingly shown to be intercalated between

May, 1916] Morphology of the Zoocecidia of Celt is 263

the cork proper and the phelloderm, which is but one cell
thick. In the region beneath the larva, the cortical parenchyma
has suffered some hyperplasia, but this is not at all comparable
in quantity to that of the phellogen.

In the case of the mechanical, laterally diverging plates,
mentioned above, it is a matter of some interest to note that
the sclerenchymatization of the two types of cells involved
is perfectly uniform or continuous. While the boundary
between the new cambium-like tissue and the cortical tissue
proper is very definite, based upon the shape of the cells, the
wall thickening processes have gone on with an equal degree of
intensity in both.

5. Pachypsylla gemma Riley. PI. XIV, Fig. 5.

As indicated in the specific name of the insect, this is a
gall of the bud. The bud incept suffers extreme modification
in its development, an irregular sub-spherical structure being
formed, containing from three to eight chambers (PI. XIV,
Fig. 5). When the chambers are numerous the structure takes
on a nodular aspect. 3-5 mm. long, 4-5 mm. wide. In many
specimens faint outlines are present, suggesting the normal
scale structure, though in no case are free scales present. The
color is lighter than that of the normal buds. Very common.
A normal bud is shown in Fig. 5 c, PI. XIV.

This gall differs from the preceding in that it is uniformly
polythalamous and always projects from the stem as a definite
(appendicular) modification of the bud. The protective layer
does not occur immediately beneath a cork layer, but differ-
entiates beneath a thick zone of tissue, which can be interpreted
as the homolog of the outer bud scale. Fundamentally,
however, the two galls are similar and they eventually may be
shown to be caused by the same species of psyllid. They are
here separated for the reason that no transition forms between
them have been observed.

In the cross section of a gall (PI. XIV, Fig. 5 a) a heavy zone
of lignified tissue is found enveloping the nutritive tissue
within. The inner walls of the chambers develop somewhat
irregular plate-like masses of mechanical tissue to support
them. In the detail drawing (Fig. 5 b), the outer zone of
homogeneous tissue is interpreted as the homolog of a bud scale.
The definite row of cells on its inner border (at x) suggests

264 The Ohio Joiirual of Science [Vol. XVI, No. 7,

epidermis. The stone-cell type of sclerenchyma forms an
extremely rigid structure. The nutritive tissue does not exhibit
the regular cambium-like formation as observed in the preceding
gall, its elements assuming an irregular aspect; those on the
inner side being tangentionally stretched. The reduced fibro-
vascular bundles traverse the outer region of the nutritive layer.

6. Pachypsylla mamma Riley. (PI. XIX, Fig. 9; PI. XV,
Fig. 6, 0 a).

A short, sub-cylindric gall on the under side of the leaf,
5-8 mm. high, 43/^-53/^ mm. wide at base, almost uniformly
arising near a principal vein. The distal end varies from a
definitely smaller diameter than that at the base, to a noticeably
larger diameter, in the first case the galls are sub-conic with
rounded ends, in the second, sub-balloon-shape, with the ends
more flattened. On the upper side of the leaf is a conspicuous
circular depression or basin, in the center of which a minute
conic papilla is evident. This papilla is part of the first gall
tissue developed, being the cone which grew up around the
larva in the process of embedding it in the leaf tissue. In
color the galls are light green, varying to violet and purple
tints. Most specimens show a definite bluish bloom. The
adult galls are smooth, though when very young they are
covered with an array of long acicular trichomes. The galls
when fully mature show interiorly a dome-shaped cavity, which
extends to the very base of the gall. This cavity is developed
through the dehiscence of the middle tissue of the nutritive
layer. A secondary chamber, variable in size, though much
smaller, is found in the region beneath the papilla. It rep-
resents the failure of the tissue above the larva to grow com-
pletely together. The walls are firm and brittle. The insects
leave the gall about the time of the first frost and as imagoes
spend the winter concealed in the bark of the tree. The galls
are more or less abundant on hackberry trees everywhere.

Riley, Johnson's Universal Encyclopedia, p. 425. 1877.
Riley, oth Rcpt. U. S. Ent. Comm. p. 618-619. 1890.

This histology of this gall has been previously studied by
Cook (2 [v. ;i p. 42()]) and Cosens (3 [p. 308]). The chief
difference between those studies and the author's is the fact
that the material studied for the present paper, disclosed the
presence of a fine canal leading in from the distal end of the

May, 1916] Morphology of the Zoocecidia of Celtis 265

gall. This will be described in a succeeding paragraph. In the
paper by Cook, the secondary chamber mentioned above was
inadvertently regarded as the larval chamber.

The specimens from which serial sections were made for
this study were not fully mature. The old mature galls are
practically impossible to cut satisfactorily. Certain features
such as the nature and development of the nutritive layer can
be studied much better in a somewhat immature gall than in
the old ones when that layer has been disrupted.

The gall comprises two epidermal layers, iso-diametrical
parenchyma tissue, sclerenchyma (protective layer) which is
particularly well developed near the dome-shaped nutritive
layer forming the central region (PI. XV, Fig. 6b).

Fig. 6d presents the details of the blind canal region outlined
at d. Fig. 6b. The epidermal cells lining the canal are slightly
smaller than those on the other parts of the gall. The cutin
layer is continuous down the canal to its blind end at the inner-
most sclerenchyma zone. A group of sclerenchyma elements,
relatively large and highly pitted, occur on the inner side of
this zone, directly beneath the canal. Inwardly the nutritive
tissue adjoining these elements is composed of exceptionally
large cells which have stiffened their walls by criss-cross thick-
enings (Fig. 6h), a type of cell not uncommon in the larger
elements of nutritive layers.

The cambium-like nutritive layer is detailed in Figs. 6c and
6e. The protective layer is well on its way in the lignification
of the cell walls though it must be remembered the condition
here illustrated is immature. In the fully mature galls, cells
near the periphery of the cecidium become lignified and the
inner cells shown in the figures finally attain walls of such
thickness as to be classified as stone-cells.

The fibro-vascular bundles traverse the gall on the under
side of the nutritive layer. On the side next to the nutritive
layer the bundles commonly possess one layer of bundle sheath
cells (Fig. 6e). The bundles collectively form a very coarse
net-work over the under side of the cambium-like central
tissue.

A detailed study of the cystoliths is shown at f and g. Fig. 6b,
PI. XV. These are illustrated in Figs. 6f and 6g, respectively.
The one on the edge of the gall shows marked abortion, evidently
possessing little calcium carbonate in its structure for it stained

20G The Ohio Journal of Science [Vol. XVI, No. 7,

heavily. The other cystolith just beyond the range of the gall
was entirely normal, the expanded part infiltrated with calcium
carbonate staining but slightly. Houard (10, [p. 109]) reports
aborted cystoliths on the border of a dipterous gall on Ficus.

Among the largest cells found in any of the galls, were some
of the parenchyma units in the old, fully mature galls (PI. XV,
Fig. 6i). Contrasting with these are the normal cells of the
leaf mesophyll (Fig. 6k), those of the petiole before their walls
are thickened (Fig. 6m), those of the pith (Fig. 6n). All
were drawn to the same scale.

The excessive enlargement of the gall cells can only go on
in those cells retaining thin walls. These cells, however,
cannot enlarge on the sides joining the lignified ones, hence
the expansion must be at the ends away from the sclerenchyma
cells. This type of development gives a characteristic radiate
structure to the parenchyma locally, where it surrounds isolated
sclerides or scleride groups, a condition presenting a striking
appearance in the section of the old galls.

The discovery of the central, extremely narrow pit or
canal in the distal half of this gall, makes it possible to correlate
it to such varietal forms as Riley's P. curcurbita, which is
smaller and presents a prominent, wide, yet deep, apical pit.
If P. curcurbita should ultimately be shown to be a distinct
species, it would as such form a transition type between P.
vesiculum and P. mamma, though it stands closer to the latter
than the former. One P. mamma gall studied failed to exhibit
the presence of the distal pit.

7. Pachypsylla venusta O. S.

This gall is a large, hard, asymmetrical, pear-shaped modi-
fication of the petiole, variable in size according to the number
of chambers found in the gall; the chamber number being
directly related to the number of insects concerned in the
formation of one gall (PI. XIX, Fig. S; PI. XVI, Fig. 7). \-2}4
cm. long, S mm. -18 mm. wide. Surface minutely roughened,
destitute of hairs. Yellowish gray to brownish in color. At
one side, near the distal end of the gall is always a prominent
concavity which is apt to be bordered by the remnants of the
leaf blade. Interiorly, radiating from a central core, the walls
give rise to conic chambers (PI. XVI, Fig. 7a). This core,
however, is attached directly to the wall of the sunken area or

May, 191G] Morphology of the Zoocecidia of Celtis 267

sinus, above mentioned. These chambers vary in number from
3 to 14. The radiating waUs are very thin near the periphery
where they join the hard outer shelL Fig. 7b shows the gall
with the side removed. The chambers are nearly filled with a
white, flocculent, waxen mass, a secretion of the nymphs. The
pupae all emerge through the thin wall of the sunken area in
the fall, and after the last ecdysis the insects fly to the bark,
where they spend the winter. These galls are not common, the
writer's entire collection numbering but a half dozen. They
have not been seen in Ohio.

Osten Sacken, B. Ent. Zeit. in Stettin, p. 422. 1861.

Before discussing the histology, it should be noted that this
gall is formed in identically the same fashion as P. mamma,
though there are many insects concerned in its development.
Once the tiny cones of tissues, which are concerned in the
embedding of all the psyllid larvae in the petiole, have over-
topped them, extensive hyperplasia takes place, this hyperplasia
eventually forming the central core. The hyperplasia of the
rest of the petiole (the peripheral portion) of course keeps pace
w^th that just mentioned.

A transverse section of the gall is shown in PL XVI, Fig.
7c. At a, is indicated a part which is enlarged nearby. An
outer and inner part of this has been drawn in detail in Figs.
7d and 7e. The first striking feature of the outer wall of the gall
is that of the presence of a cork layer on it. Kiister (16 [p. 206])
points out that cork formation on galls is a rarity. No cork, of
course is ever found on the normal petiole. The cortical
parenchyma cells have not thickened their walls as those of the
normal petiole do. An extremely heavy layer of stone cells is
developed, but is not continuous; numerous strands of par-
enchyma tissue extend through it. The nutritive layer (Fig. 7e)
consists of the same thin walled type of tissue seen in that of the
other galls, but it does not possess, in the adult condition,
the typical cambium-like structure. The fibro-vascular bundles
located in the outer part of the nutritive layer are small and
numerous (much more so than indicated in the diagram). No
bundle sheath is developed.

The central core is composed of a homogeneous mass of
very large sclerenchyma cells. One of these is figured, Fig. 7f.
The simple pits in the wall extend as far as the middle lamella.
Fibro-vascular tissue is entirely absent from the core, a fact

268 The Ohio Journal of Science [Xo\. XVI, No. 7,

related to the origin of the structure, for the embryonic tissue
concerned in its development never was related to the pro-
cambial strands, but was entirely new hyperplasia tissue. The
pores leading from the chambers through the core are lined
with short multi-cellular trichomes. (Fig. 7g).

Fam. Itonidid.e (Ord. Diptera).

This family, formerly known as the Cecidomyiidse, embraces
a large assemblage of gall makers. In the vast majority of
cases, the egg is deposited superficially on the very young
plant parts. The gall does not begin development until the
larva hatches out and places itself in intimate contact with the
embryonic plant tissue. This is followed in the galls found on
the hackberry, by an upward growth of the tissue about the
larva. The tissue above the larva never completely grows
together, leaving what is called in the present paper an ' ' apical
canal. " This very common type of gall is called by Kiister the
" umwallungen " form, a word very satisfactorily expressing
the real nature of the gall. This type of cecidium stands in
marked contrast to that in which the larva sinks into a diverti-
culum or pouch, a kind found on the leaf blade only.

Of the nine galls set forth in this paper, only three have had
the adult insects associated with them described and named.
Patton (26) in order to illustrate a method of naming galls,
gave specific names to a few of the following galls, which Riley
(28) had described, but properly left unnamed. Riley did not
have the adult insects and Patton did not see Riley's galls,
so we have the interesting case of a gall insect being named
without the writer having seen either the gall or the insect.
These names of Patton's are omitted from the present paper.

The galls described for the first time in this paper, are given
a list number, which can be referred to by the entomologist
who finally describes the adult insect. The heretofore unde-
scribed galls and those yet unnamed are placed provisionally
under the old genus name Cecidomyia, which has long served
as a "storage" place for itonid "insect^e imperfectas".

All of the galls are not worked out to the same degree of
detail since they are of fundamentally different structure.
Two of the simpler forms, exhibiting contrasting specific
characters, have been chosen to adequately present, by full
treatment, the histology of the itonid types on the hackberry.

May, 1916] Morphology of the Zoocecidia of Celt is 269

The author, at this point, wishes to express his deep apprecia-
tion of the kindness of Dr. E. P. Felt, State Entomologist ot
New York, the American authority on the Itonididae, for
many helpful suggestions pertaining to the identity of some of
the gall forms herewith presented.

Riley (28) describes one gall which has not been collected
by the writer. To give a character of completeness to the
itonid list, his data on this form will be given.

"33. On the under side of the leaf, arising from the leaf
ribs, occurring either singly or in smaller or larger groups.
Gall rosette-shaped, resembling the seed capsule of certain
Malvaceous plants of the genus Hibiscus, circular in outline,
greatly flattened on top and here furnished with a short central
spine or nipple (frequently broken off) ; sides sulcate, with from
ten to twelve more or less marked furrows, and with the cor-
responding interstices convex. Surface of gall not shining,
lighter or darker brown, speckled with small, irregular, blackish
pustules, and sparsely beset with moderately long whitish
hairs, which are easily abraded. Average height of gall, .75 mm. ;
diameter 2-3 mm. Cell oblong oval, enclosed by thick, woody
side walls, but with a thin bottom, and at the roof (i. e. toward
the upper side of the leaf) covered with a thin soft layer. The
gall is at once recognizable from its shape, but might readily
be mistaken for a Psyllid gall" Riley.

This gall is probably Cecidomyia "lituus" Walsh, which
is given by Felt as a "yellowish, disk-shaped gall with acute
apical cone on leaf." Walsh's name "lituus" should not be
associated with any hackberry gall. In the citation below he
gave this name to the grape gall now called C. viticola, and
mentioned, merely, the presence of two "similar galls" on
hackberry leaves.

Walsh, Am. Ent. 2:28. 1869.

Riley, 5th Rept. U. S. Ent. Comm. p. 613. 1890.

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

8. Cecidomyia unguicola Beut. (PL XVII, Figs. 8, 8a).

On leaf, under side, a, sharply pointed cone-shaped gall
with flaring base. 3-5 mm. high, 2-3 mm. wide. Light green
to yellow in color. Smooth, almost shining. Monothalamous,
rarely, if ever confluent. Chamber sub-cylindric, with the
distal half thinner walled than the proximal. The distal one-
third or one-fourth of the gall is delimited proximally by the

270 The Ohio Journal of Science [Vol. XVI, No. 7,

sudden transition from delicate sub-hyaline tissue to opaque
hard tissue. Sooner or later the tip breaks off at this point.
Riley states that "while issuing the perfect insect pushes off
the tip." This gall is the most common of all the itonid galls
of the hackberry; a hundred may often be found upon a single
leaf.

Rilev, oth Rept. U. S. Ent. Comm. Gall No. 34, p. 614. 1890.
Beutenmuller, Bull. Am. Mus. Nat. Hist. 23:388, PL 13, Fig. 9. 1907.

The entire longitudinal section of this gall is illustrated in
detail in PI. XVII, Fig. 8a. This figure and the next are
slightly diagrammatic in that the fibro-vascular bundles, which
traverse the gall longitudinally without branching, are shown
continuous, when actually they would be broken in any one
of the serial sections, due to the fact that they do not pass to
the tip of the gall in one plane.

The epidermis is uniformly composed of simple tan-
gentionally flattened cells. The nutritive and protective layers
assume an elongate cup shape, whose base is surrounded by the
parenchyma tissue, which gives the gall base its flaring aspect.
The nutritive layer is very thin, seldom over three cells in thick-
ness. Note the unbroken condition of its superflcial cells.
The larvcB in all of the galls of this type do not feed on the cell
tissues, but on the food material which passes into the chamber
through the cell walls. The protective layer is sharply delimited
from the nutritive, a condition common to all of the itonid
galls studied. On its outer side the protective layer is only
sharply set apart from the parenchyma on the side toward
the leaf.

The nature of the cells composing the protective layer is
shown in Fig. 8d, a small group of cells at the proximal end
of the layer. The walls contain innumerable simple narrow
pits, which pass to the middle lamella. This latter structure
is in all cases continuous between the cells. Crystal cells are
found in abundance directly adjoining the lignifled thick walled
cells, a condition obtaining in the normal stem (PI. XII, Fig. A).
Figs. 8e and 8f show the sclerides of the 1 yr. and 3 yr. old
stems respectively, and are drawn to the same scale as those
from the gall. The great majority of the lignifled cells of the
galls are largei inan any found in the stem or in the stone of
the fruit.

May, 1916] Morphology of the Zoocecidia of Celtis 271

The distal one-third of the gall is composed of rows of very
thin walled cylindrical cells. Distally the inner superficial
layer of these give rise to numerous coarse trichomes, which
choke the apical canal leading to the larval chamber.

The fibro-vascular bundles are not as large in proportion
to the rest of the tissues as the principal bundles of the leaf.
Their number and distribution are shown in Fig. 8b. Basally
they are related directly to the bundles of the leaf or as is often
the case they form a "knot" in the median basal region, this
"knot" being related to a number of leaf veins. Kiistenmacher
(14) finds a similar "knotted" condition of the bundles at the
base of certain Rhodites galls. The xylem elements are fine
spirally thickened tracheids. The phloem cells are simple
elongate cells whose end walls slant at a more or less prominent
angle. No bundle sheath tissue is evident; the proximity
of the bundles to the rigid protective layer making possible
their support without the normal mechanical tissue being
present.

The normal leaf (Fig. 8a) is very little affected where the
gall is attached to it. The epidermis with its cystoliths and
two palisade layers, exhibits hypertrophy, but this not to a
marked degree. It is evident that the primordium of the
spongy layer has furnished the basis for the hyperplasia con-
stituting the gall.

In the chamber region is shown the section of the larva.

9. Phytophaga celtiphyllia Felt. (?) PI. XVIII, Figs. 9, 9a.

A sub-balloon-shaped gall occurring on the leaves (either
side), petioles and stems. 4-8 mm. high, including the apical,
variable, attentuate tip, which arises sharply from the distal
end of the gall body. 4-53/2 mm. dia. through the broad
distal half of the gall. The sides do not taper proximally
in the typical balloon fashion, but show a definite constriction
below the distal expanded portion. When isolated the galls
show a perfect radially symmetric structure, but they are apt
to be found in clusters, resulting in more or less loss of symmetry
through mutual pressure. When on the leaves they generally
are found on the upper side attached close to the principal
veins. These galls retain their green color longer than any of
the others ; when full size in mid-summer, the content of chloro-
plasts in the superficial cell layers is so great as to make them

272 The Ohio Journal of Science [Vol. XVI, No. 7,

fully as green as the leaf. Coarsely pubescent. The chamber
is constricted distally. Galls not uncommon in Kansas, but
this form has not been seen in Ohio.

The writer is practically certain that this is the gall described
by Pergande, whose notes are presented by Felt with the descrip-
tion of the above insect. Pergande states it to be a "very
hard, obconic gall, the upper extremity produced as a long
slender nipple; at the base five or six low ridges. The galls
occur on the upper side of the leaf and drop when mature."
Unfortunately no measurements are given. On the basis of
the brief description, however, absolute certainty is not possible.

Felt, N. Y. State Mus. Bull. 180, p. 216. 19U.

The histology of this form, (PI. XVIII, Fig. 9a), while
fundamentally similar to that of C. unguicola, just described,
presents many points which are of particular interest when
contrasted with the features of the other gall.

A specimen on the leaf was chosen so that the two galls
can be said to have a similar origin. The distal expanded
or flaring portion of this gall (8) is seen to be due to the develop-
ment of a mass of large celled parenchyma, comparable to
that found in the proximal part of 7. The protective layer
is thicker and divides distally so as to form a definite support
for the mass of parenchyma just mentioned. The nutritive
layer is extremely well developed; the thickest of any of the
itonid galls. It will be noted that it is intact. The apical
canal of the gall is not continuous into the chamber, the walls
at its inner end having become tightly pressed together. The
line between the two epidermises, however, was easily found in
the serial sections used. The outer part, of definite diameter, is
choked with slender trichomes, which are certain of the epi-
dermal cells greatly elongated. The fibro-vascular bundles
traverse the protective layer. Much more of the leaf is involved
in this gall than in number 7 (Fig. 9a). In that portion of the
leaf involved, the usual inhibition of the normal differentiation
has ensued, the hyperplasia consisting of little more than a
mass of parenchyma bearing greatly hypertrophied epidermal
cells (gall trichomes) and the vascular tissue. As in all of these
galls, no cystoliths or stomata ever were seen associated with
the hyperplasia tissue. The longitudinal section of the larva is
indicated in the chamber.

May, 1916] Morphology of the Zoocecidia of Celtis 273

Fig. 9b shows the detail of the region indicated at Fig. 9a, b.
The simple-pitted sclerenchyma cells differ only in the shape
they have assumed on either side of the vascular bundle. On
their outer side they are bordered by crystal "sacs," a relation
which as observed earlier, obtains in the normal stem. More
highly magnified sections of these cells are shown in PI. XVII,
Fig. 9c.

10. Phytophaga wellsi Felt. Cecidium nov.

(PI. XVII, Figs. 10, 10a).
On leaf, under side, more or less definitely obconic, resembling
the shape of a somewhat flattened top. Generally found in
clusters attached to the sides of the principal veins near the
point of their divergence from the petiole. 2,}/^-S mm. high,
3-4 mm. wide. Distal end shows a more or less definite
central prominence. Yellowish tinged, with short pubescence.
Walls pithy in texture, yet firm; tissue when old, brown.
Chamber sub-cylindric. Protective layer poorly developed,
confined to proximal one-third of gall. Nutritive layer very
thin. Fibro-vascular bundles traverse galls near the surface.
This is the simplest of all the itonid galls studied.

Description of adult insect b}^ Dr. E. P. Felt, in manuscript.

11. Cecidomyia sp. (PI. XVII, Figs. 11, 11a).

On leaf, under side, a small (2-3 mm. long, 1-1^2 mm. wide)
sub-cylindric gall with attenuate tip, which is more or less defin-
itely constricted from the body of the gall. Base rounded, light
green to yellow, smooth. Thin walled, the chamber approxi-
mating the shape of the gall. The galls are commonly tilted
over at a sharp angle, particularly when they arise from one
of the larger veins. The protective and nutritive layers are
distributed much as those of No. 7.

Riley first described this gall (No. 35 in his paper) and called
attention to its similarity to C. unguicola Beut. (See No. 8).
It differs constantly from that gall, however, in its smaller size
and its non-flaring base.

Riley, 5th Rept. U. S. Ent. Comm. p. 614. 1890.

12. Cecidomyia sp. (PI. XVII, Figs. 12, 12a).

"On leaf, under side, stoutly conical and nippled at tip.
Succulent, pale green, and covered with fine bloom when young.
3x4 mm. Present in great numbers; larva, white." Sears.

274 The Ohio Journal of Science [Vol. XVI, No. 7,

The author's specimens rarely go over 3 mm. in high.
They vary from 2-3 mm. in width. Many are purplish tinged.
The chamber is sub-cylindric. rounded below.

The protective layer is well developed and extends distally
as far as the inner opening of the apical canal. The nutritive
layer is confined to the proximal half of the chamber wall.
The fibro-vascular bundles pass upward close to the protective
layer.

Sears, Ohio Nat. 15:384. PI. 19, Fig. 33. 1914.

13. Cecidomyia sp. (PI. XVII, Figs. 13, 13a).

"Leaf gall, present in great numbers on under side. A
"peg-shaped" gall, cylindrical when young, and developing
a thickened base as it grows. Pale green, straggling hirsute,
2-3 mm. long. Very common." Sears.

The broad, ill-defined ridges which characterize the base of
this gall separates it from all others. The protective layer is
relatively thick, but does not extend into the wall of the distal
end. The nutritive layer is thin. The fibro-vascular bundles
pass through the parenchyma basally but approach the pro-
tective layer apically.

Young specimens of this gall would closely approximate

the gall described in Riley's report under No. 30. The expanded

condition of the base is not gained until the gall has nearly

completed its growth in length.

Riley, 5th Rept. U. S. Ent., Comm. p. 612. 1890.
Sears, Ohio Nat. 15:384. PI. 19, Fig. 35. 1914.

14. Cecidomyia sp. (PI. XVIII, Figs. 14, 14a).

A large, globular, mucronate tipped gall of the stem. 5-8 mm.
dia. Base varies toward a truncate condition in some speci-
mens. Green throughout the summer; finely pubescent.
Chamber large, spherical. A thin membrane is constructed
by the larva across the distal end of the chamber. Protective
layer thick, nearly half as thick as the wall. Does not extend
to apical canal. Nutritive layer relatively thin. The fibro-
vascular bundles traverse the protective layer.

Riley describes a globular gall, which on "detaching the
gall, the base is seen to be truncate and attached to the rib
of the leaf by an extremely short, conical style, which is not
visible from the sides. Average height, 3.5 mm., dia. at
middle, 3.5-4 mm." See No. 32 in Riley's fist. This gall

May, 1916] Morphology of the Zoocecidia of Celtis 275

might be interpreted as an immature specimen of the above.
Sear's number 34 is a variation of the above with the basal
one-third developing low irregular ridges.

Riley, 5th Rept. U. vS. Ent. Comm. p. 613. 1890.
Sears, Ohio Nat. lo:3S4, PL 19, Fig. 34. 1914.

15. Cecidomyia sp. (PI. XVII, Figs. 15, 15a, 15b.)

This gall exhibits a remarkable variation from the previously
described simpler types. Riley, who first described it, gave
a very complete description of it, which will be quoted.

"31. Galls on the tender twigs, occurring either singly or
in groups of two, three or four or more specimens; rarely
also singly on the under side or even the upper side of the leaf.
The gall bears a close resemblance to the winged seed capsule
(achenium) of a Rumex, but the wings vary in number from
three to five and are often irregularly developed, while the tip
always ends in a curved, long spine. The wings terminate in a
sharp ridge which is sometimes double. Gall opaque, not
hairy. Color pale-yellowish green, at apical third usually of a
more decided green and darker. A longitudinal section reveals
a single large regularly ovoid cell surrounded by a thin hard
wall. Average height of gall, 4.5 mm., excluding the apical
spine; generally as wide as high; length of apical spine variable,
but usually a little more than half the height of the gall."
Riley.

The histology presents some points of special interest. The
fibro-vascular bundles are found in the edge of the wings
(PI. XVII, Fig. 15b), from which branches are distributed
inwardly to the protective layer. This is better shown in the
longitudinal section. Fig. 15a. The protective layer is found,
as in most of the preceding galls, to be confined to the proximal
two-thirds or three-fourths of the chamber wall. Trichomes
line the apical canal to the point where it opens in the chamber.

16. Cecidomyia sp. Cecidium nov. (PI. XVIII, Figs. 6,

pi. XIX; 16, 16a).
A gall of the leaves, stem, petiole or fruit occurring generally
in an aggregate condition. An isolated specimen on the stem
will be described to elucidate the fundamental unit character-
istics (PI. XVIII, Figs. 16, 16a). When found singly, the gall
is irregularly conic or sub-cylindric, with a very blunt truncate
tip. The chief character is involved in the fact that the gall

27G The Ohio Journal of Science [Vol. XVI, No. 7,

eventually drops its larval chamber enclosed by the nutritive
and protective layers. This central part of the gall which
slips out has the shape of a short, blunt horn. The tapering
of this structure toward the proximal part of the gall makes
possible the easy departure of this larva containing portion
when the dehiscence layer surrounding it gives way. The gall
aggregates commonly occur at or near the end of the stem, the
tissue, after the larval chambers have fallen, dying, turning
black, giving the twig an unsightly appearance (PI. XIX, Fig. 6).
In the case of a single gall (PI. XIX, Fig. 4) the stem is not
killed, but the tissue of the "socket" part is cut off by an
abscission layer (Fig. 16a, PI. XVIII).

The gall on the fruit (PI. XIX, Fig. 8) possesses exactly
the same structure as those on other parts of the plant. The
galls shown are not mature, the chamber not having burst
through the surrounding supporting tissue. In section (PI. XIX
Fig. 4) the galls are seen to project into the ovulary cavity,
exhibiting in their entirety the characteristic shape observed
in those of the leaf which project from both sides of the leaf.
The ovule is aborted.

The most important histological feature is naturally
associated with the chief feature of the gall and consists of
the dehiscence layer developed around the protective layer.
This layer (PI. XVIII, Fig. 16a) is made up of extremely thin
walled cells, arranged in rows, radiating from the protective
layer. It gives evidence of having been formed by rapid
division when the gall was nearing maturity and becomes
intercalated between the fibro-vascular system and the pro-
tective layer. Its eventual disintegration separates it cleanly
from the protective layer, leaving the central part containing
the larva free to be shaken out by the wind.

A few similar types of galls are known among the Cynipidas
and Itonidid^. Houard (11) figures an itonid (Oligotrophus
Reaumurianus Loew) which is exactly similar. It occurs on
Tilia grandifolia of Europe.

Comparative Studies.
Kataplasmas.

The two kataplasmas (galls 1 and 2) possess differences
related in part to the position of the parasites on the stem. The
excessive hyperplasia of the cortex, in the case of the witches-
broom branch bases, seems to be associated with the superficial

May, 1916] Morphology of the Zoocecidia of Celt is 277

position of the mites, while in the case of the lepidopterous gall
the greatest hyperplasia is that of the pith, the medullary rays
and cambium region, a condition correlated with the internal
position of the larva.

Suppression of normal differentiation characterizes both.
The lepidopterous gall partially developes bast, but no sclerides
appear. The mite gall exhibits sclerides, but no bast. No
lignification of the undifferentiated xylem cells occurs in the
lepidopterous gall, but is very definitely found in the acarinous
cecidium.

Compared with the normal stem, the most significant
single fact concerning the kataplasmas, is the marked inhibition
of differentiation with no substitution of entirely new tissue forms.

Prosoplasmas. Hemipterous galls.

Pachypsylla vesiculum (gall 3 and Fig. 3) is the simplest
of the psyllid galls. Compared with the normal leaf it would
appear that the middle cells of the immature mesophyll are
most susceptible to the influence of the nymph, since these
cells have carried out the hyperplasia.

The other four galls are all fundamentally identical in
structure and mode of development with that of P. vesiculum.
Gall 4 is the abnormally differentiated bud primordium.
Gall. 5, (P. gemma) has developed for the most part from the
stem phellogen, a tissue in the young stem undoubtedly more
susceptible to control than that of the cortex. Gall. 6 (P.
mamma) involves all of the leaf tissues, so that the gall can be
considered as a mass of "new" tissue intercalated in the leaf
blade, but suspended below the leaf blade plane. Gall 7 (P.
venusta) illustrates the same mode of development seen in
No. 6, carried out on the petiole by a number of larvae rather
than one. (See description under 7).

It can be said that the above psyllid galls, characterized
by little or no " umwallungen " development with rather ill-
defined protective layers surrounding nutritive tissue possessing
a cambium-like structure, constitute a generic type of gall for
the hackberry, a type which contrasts strikingly with the
generic type of itonid galls.

It is of course evident that the specificity of the different
galls is in part due to the instinctive behavior of the insects in
choosing particular plant parts. This is strikingly shown by
comparing P. mamma with the gall on the side of stem (No. 4).

278 The Ohio Journal of Science [Vol. XVI, No. 7,

The evagination beneath the larva so prominent in the case of
P. mamma could not, naturally be carried out on the stem, hence
the hyperplasia in that case is almost entirely lateral to the
insect and above it. Discounting the factor of the plant part
selected there is the quantitative evidence indicating specificity
in the intensity of the stimulus which developes the generic
type of gall.

Compared with the normal tissues these galls show the
abortion or complete absence of certain normal specialized
cells, such as stomata, cystoliths, tracheae, bast, wood fibres
and sieve tubes.

Prosoplasmas. Dipterous galls. (Itonididas).

Galls of Cecidomyia unguicola (S) and Phytophaga celti-
phylla (9) were chosen to illustrate in detail the definite speci-
ficity which characterizes these highly evolved forms of proso-
plasmas, which are induced by the insect larva to grow upon the
same leaf. This fact of the gall species being definitely and
constantly related to the insect species, is a fact of far reaching
significance. It has long been known among European workers
and Cook (2) on a histological basis, first called attention to it
in America.

In the case of these two galls some of the contrasting
characters are: Notable difference in size (they are drawn to
same scale). In 8 the proximal development of large celled
parenchyma, opposed to its distal development in 9. Much
thicker protective and nutritive layers in 9 than in 8; shape of
layers also different. Apical canal tightly closed proximally in
9, open throughout in 8. Trichomes in apical canal of 9 smaller
than those in canal of 8. Large acicular trichomes developing
over surface of 9, while 8 is always perfectly smooth. Hyper-
plasia of leaf at base of gall, extends much farther in 9 than 8.

Comparing the other itonid galls in a similar manner will
yield just as striking results. In the following discussion of the
remainder of the galls, only the more significant specific
characters will be emphasized.

Phytophaga wellsi (10) is the least specialized. Its pro-
tective layer merging insensibly into the distal parenchyma and
its simple closed apical canal are the two most important
characters placing it below the others in the degree of complexity
attained.

May, 1916] Morphology of the Zoocecidia of Celtis 279

No. 11 is similar to 8, but simpler. It is constantly smaller
and does not develope the expanded base, so characteristic of 8.

The extension of the protective layer to the apical canal is
found in No. 12 only.

In No. 13, the epidermis lining the chamber at the apical
end of the gall is composed of perpendicularly elongated cells
which are filled with a fine granular substance (Fig. 13b, at x,
pi. XVII), the nature of which was not determined. The char-
acter was constant, being exhibited in many galls examined.
Such a cell layer was not observed in any other itonid gall.

No. 14 has the fibro-vascular bundles traversing its sharply
defined protective layer. In this respect it is similar to 9.
These two galls differ from all the others, having definite
protective layers, in this character. Kiistenmacher (14) has
noted the diversity in Rhodites galls in this regard.

The alate condition of 15 makes it an object instantly
indentifiable. With this character is associated the peculiar
distribution of the bundles (Fig. 15a, pi. XVII), not found in
any other gall.

No. 16 possesses many characters setting it apart from the
others, the most important of which is the development of the
dehiscence layer in it, permitting the larval chamber to drop out.
Nothing in any of the other galls is directly comparable to it.

All of the hackberry itonid galls are of the " umwallungen "
generic type. The kinds of cells found in the galls are not widely
dissimilar, the specific characters being confined to the kinds of
tissues, with particular reference to the form the tissues assume.

There is a character which the writer desires to point out,
which is found not only on most of the itonid galls of the
hackberry, but on those of other plants, the significance of
which has not been determined so far as the author is aware.
The protective layer in most of these galls is sharply delimited
apically giving rise to a distal segment of the gall composed
wholly of parenchyma (No. 12 excepted) a segment which is
evident in many galls upon superficial examination.

It is proposed to call this segment the "apical segment,"
though the writer has not used this terminology in the present
paper because of the uncertainty as to its value in taxonomic
description. No ontogenetical studies of this type of gall
have as yet been made by the writer to demonstrate if this
apical segment bears any relation to the minute cone which
early developes over the newly hatched larva.

280 The Ohio Journal of Science [Vol. XVI, No. 7,

In way of summary it can be stated that the hackberry
itonid galls exhibit in an especially strong fashion, specificity,
based upon the generic " umwallungen " type of cecidium.
This specificity is directly related to the specific physiological
phenomena of the larva and holds, whether the gall appears
on the young tissues of the leaf, petiole, stem or fruit. The
insects commonly, however, tend to oviposit on a particular
plant part, (this probably being the most important factor
in determining the position the larva eventually takes), and
the galls thus become associated with that part. But as in the
case of 16, it is seen that the character of the gall's position on
the plant would be of no taxonomic value whatever, since these
galls have developed from the young tissue of leaf, petiole,
stem and fruit. Many of the others have been reported from
more than one plant part.

The comparison of the two generic types of prosoplasmatic
galls will yield some interesting data.

Of the psyllid galls Pachypsylla mamma (6) shows best the
generic type to which it belongs. Occurring on the leaf it
can be contrasted to advantage with the numerous itonid
leaf galls. Given the P. mamma larva and an itonid larva (one
like Nos. 9 or 1,3, which commonly form galls on the upper
side) on the same young leaf, on the upper side there will occur
an entirely different series of changes as evidenced in the final
stages, the mature galls. In the case of the psyllid the minute
"cover" cone which grows up around the larva, remains small,
the gall being composed almost wholly of hyperplasia tissue
beneath and to the sides of the larva. The larva is lowered, as
it were, in a downward evagination, the sides of which growing
inward above eventually developing a thick wall over the
larva. The primal "cover" cone does not contribute to this,
but remains small and can always be seen in the center of the
upper concave side of the gall as a minute papilla.

In the itonid gall very little hyperplasia takes place beneath
the larva, the gall being developed from the primal "cover"
cone, the gall becoming an appendicular structure on the
upper side of the leaf, while in the psyllid it is on the under.
Most of the itonid larvae begin operations on the under side of
the leaf, resulting in the gall having that position, but this does
not destroy the significance of the fundamental difference
between the two types of galls.

May, 1916] Morphology of the Zoocecidia of Celt is 281

Histologically the itonid galls show a much higher condition
in the definiteness with which the nutritive, protective and
parenchyma tissues are distributed. Also, greater diversity
of specific characters is introduced by the larvce, in itonids
than in psylhds for in the latter a definite part of the form
character is related to the kind of plant part on which the gall
is developed. In the itonids the form character is wholly
related to the larva.

Comparing the prosoplasmas with the normal tissues it is
strikingly evident that we have, as many European cecidologists
have pointed out, entirely new structures. This "newness,"
however, in the hackberry prosoplasmas, consists of new forms,
assumed by tissues, which are composed of cells that have
close if not identical counterparts in the normal parts. Com-
monly the parenchyma and sclerenchyma elements of the gall
tissues are much larger than those found in the unaffected
structures, but in no case can it be said that the cells of the galls
are fundamentally different from those observable in the
normal plant.

Heteroplasmas, (All of the galls).

In comparing the kataplasmas with the prosoplasmas, it can
be inferred that the amount of embryonic tissue influenced in
the beginning stages of the gall is greater in the former than in
the latter. In the case of the lepidopterous gall the fact of
the greater range of the stimulus is doubtless associated with
the relatively greater size of the larva; in the mite gall, to the
numerous individuals present at a particular point of attack.
In both cases this condition is enhanced by the migration of the
arthropods from one part of the affected region to another, a
phenomenon known to take place in these galls, but which
is not true of the prosoplasmas. In these the larva is quiescent,
while the definite new form of tissue is growing about it. This
has been demonstrated by the writer in P. mamma and by
Fockeu in dipterous galls. The low type of heteroplasia
(kataplasma) relatively undifferentiated, and the highly differ-
entiated form (prosoplasma) undoubtedly owe their difference
in great part to the distinction in the arthropods just pointed out.

It should be noted that the difference between kataplasmas
and prosoplasmas is not a difference in kind, but a difference in
degree only, as Kiister (15) pointed out when first presenting
this terminology.

282 The Ohio Journal of Science [Vol. XVI, No. 7,

The xylem of the kataplasmas showed the presence of sub-
normal tracheae, while that of the prosoplasmas, even though
occurring on vessel bearing parts, always possessed narrow,
elongate, spirally thickened tracheids only.

All of the galls when compared with normal parts show
partial or total suppression of normal tissue characters and the
substitution of new characters. The new characters, no matter
whether little or greatly divergent from the normal, are
specifically related to the arthropod concerned in calling them
forth.

In all of the galls, except the lepidopterous one (2), lignifica-
tion of certain parenchyma elements has taken place, giving
rise to more or less definite sclerenchyma tissue forms (pro-
tective layers), which in no case finds a counterpart in the
normal plant. This layer doubtless is definitely functional in
preventing mechanical injury to the larva.

General Considerations.

This paper does not deal directly with the etiological
problem, the greatest problem in cecidology, but does deal with
it indirectly in attempting to make clearly evident, the phe-
nomena appearing at the end of certain gall ontogenies; the
phenomena to be explained (it is hoped) through etiological
investigations. At this point it might be well to state (for
it is a fact not generally known) that the nature of the stimulus
applied by the insect is not known. Magnus (20), whose recent
work presents an excellent summary of the etiological problem,
closes with this sentence: " Der hypothesen sind genug
gewechselt, lasst uns auch endlich Tatsachen sehen." All
the evidence arising out of experimental studies of the problem
point toward a chemical interpretation (enzymes, etc., secreted
by the larva), but as Kiister (17) repeatedly has pointed out,
the experimental evidence definitely supporting any chemical
interpretation does not yet exist. In the true scientific spirit
he acknowledges the chemical theory to be, as yet, a necessary
inference only.

From the preceding comparative studies, particularly those
of the prosoplasmas, it is clearly evident that the gall rep-
resents something new as far as the form content of the tissues
and their particular orientation is concerned. The particular
combination of sclerenchyma form, parenchyma form, and

May, 1916] Morphology of the Zoocecidia of Celtis 283

bundle tissue, observable in any of the prosoplasmas, does not
even find an analogy in the normal structure. The cells of the
galls, however, all have their homologs in the normal tissues.
Cosens (3) states: "The conventional view to account for
these phenomena is that the protoplasm has been endowed with
entirely new characteristics and power to produce something
foreign to the normal host. But this probably is true only in a
very limited sense for according to my experience at least the
prototypes of such apparently new tissues, etc., have been
found elsewhere in the host or its relatives." He bases this
statement on a comparative study of special structures, such as
"glands, trichomes and aeriferous tissue," which reappear
in certain galls in addition to the definitely new tissue "forms,"
constituting the gall as a whole. Any comparative studies of
cecidia and normal parts should take into consideration the
whole structure and when this is done the essential "newness"
of the cecidium appears.

In the form characters of the gall tissues (gained through
growth, i. e., proliferation and differentiation of cells) we
have characters, which without any doubt whatever, are
ascribable to the specific physiological phenomena of the
insect. In other words the insect larva controls the growth
of the embryonic tissue in its immediate vicinity, this growth
developing a new structure, showing specific characters as
definite and constant as the group of characters observable
in the adult insects. A glance at plates 6 and 7, showing nine
species of itonid galls, all but one of which have been seen
by the author, on Celtis leaves, will demonstrate to any one
the validity of the above statement.

An analysis of form character can be made, which will
disclose certain factors over which the insect has undoubted
control.

Form character with respect to tissues in the normal plant
is directly related to the orientation of the mitotic spindle
axes and the number of divisions during growth, and the sizes
attained by the cells after mitotic activity has ceased. These
factors are of course influenced by the ever present factor of
environment. To the growth factors should be added the
factor (the nature of which is unknown) which directs differ-
entiation. In thejgall problem this is particularly involved in
the appearance of_the lignified sclerenchyma tissue (protective

284 The Ohio Journal of Science [Vol. XVI, No. 7,

layer), which in all cases represents a zone of parenchyma cells,
which change their activity from growth to thickening of their
walls.

In the case of the development of a number of species of
galls on a particular leaf, the physical environmental factor
can be thrown out, since it is the same for all. It is the biological
environmental factor (the larva) which is now the external factor
controlling the internal ones operative in developing tissues.
These internal ones, to state them again are: The factor or
factors related to the orientation of mitotic spindle axes and
the number of mitoses carried out; the sizes attained by cells
after mitotic activity has ceased; the factor or factors directing
the distribution of differentiation products, which in this
morphological study has particular reference to the thickening
(lignification) of walls. Any theory concerning the nature of the
stimulus should adeciuately explain how the particular stimulus
exercises its control over the above factors, which factors,
be it noted, are the most important factors entering into the
growth of tissues.

It should be noted in the above analysis care has been taken
to definitely distinguish between the factors related to the
development of particular kinds of tissues and those related to
the development of particular kinds of cells. These distinctly
intra-cellular factors making possible mitosis, growth in size
of cell, lignification of cell wall and the like, it would appear
are practically undisturbed, for from the standpoint of the cells
there is little or no fundamental difference between those
simpler ones in host tissue and those in the galls. It should
be remembered, however, in this connection, that highly
specialized cells, such as cystoliths, etc., do not appear in galls.

Before leaving this phase of the subject, attention should be
called to the fact that much evidence exists to show that these
fundamentally new gall tissues are carrying out fundamentally
new functions. This material, however, would be out of place
in a paper intended to be purely morphological.

Material of some interest may be forthcoming if we view the
above conclusions in the light of modern genetic conceptions.

Cosens (3) states, "this much is certain that there appears
to be an entire lack of evidence supporting the view that the
protoplasm of the host has become endowed with a property
that enables it to produce a fairly definitely shaped but withal

May, 1916] Morphology of the Zoocecidia of Celtis 285

abnormal structure. Such a pronounced change would surely
be expressed in the heredity characteristics, yet there is not a
vestige of proof tending to show that insect galls ever produce
the slightest variation in the descendants of the host." The
"protoplasm" referred to above is the germ plasm and, used in
this sense the statement made, is correct. While nothing is
known concerning the difference in the meristematic tissues
of gall bearing plants as opposed to non-gall bearing forms, there
is no reason for hypothesizing a special constitution for the
germ plasm of the gall bearing flora. Nearly all of the orders
of the Anthophyta possess gall bearing plants.

On the contrary, morphogenetical studies constantly and
definitely point to the germ plasm of the insect as the place of
origin of gall forms. These gall forms (tissue forms taken
collectively) are almost without exception found to be specif-
ically related to the insects associated with them, this being
exhibited in the most striking manner in all of the higher
prosoplasmas. In the prosoplasmas it can, with certainty, be
said that we have the remarkable and unique case of the over-
lapping, as it were, of an animal hereditary constitution on
that of a plant ; a situation in which the plant's tissue "forming"
factors (not tissue growing factors) are suppressed and new ones
substituted. In this connection it should be remembered that
in the early stages of all prosoplasma ontogenies, the larval
insect is in contact with the undifferentiated plant tissue; a
contact as intimate as that between one part of a growing
plant and an adjoining part. Fockeu (6) correctly states that
the early phenomena observed in the reaction of the plant part
is "en rapport" with the "phenomenes vitaux" of the gall
inducing form.

Since science knows little or nothing concerning the mechan-
ism by which hereditary factors are enabled to come to expres-
sion in form and otherwise, it is suggested that in the
zoocecidological field, we have a unique place to attack this
problem. Hybridization of gall insects to see if the Fi and
succeeding generations of galls would follow known hereditary
laws, undoubtedly would prove an extremely suggestive line
of investigation. But the great discovery which will undoubt-
edly go far toward helping us understand the mechanism of
heredity will be that of the exact nature of the stimulus involved
in producing these problematic plant tissue forms, comprising
the prosoplasmatic zoocecidia.

286 The Ohio Journal of Science [Vol. XVI, No. 7,

Summary.

1. There are seventeen known species of zoocecidia occur-
ring on Celtis occidentalis, belonging to four orders of arthro-
pods: Acarinae 1, Lepidoptera 1, Hemiptera 5, Diptera 10.
All are heteroplasias, i. e., those forms of hyperplasias (abnormal
increase in size through cell proliferation) whose cells and
tissues differ from the normal. All, be it noted, are built up on
the basis of the same germ plasm, viz., that of the single species
of the plant mentioned.

2. The acarinous and lepidopterous galls are kataplasmas,
or those forms of heteroplasias whose cells and tissues do not
vary widely from the normal. Each shows specific and char-
acteristic inhibition of differentiation.

3. The hemipterous and dipterous galls are prosoplasmas
or those forms of heteroplasias whose cells and particularly
whose tissue forms differ fundamentally from those of the
normal parts. Each of these galls shows definite specificity. In
the hemipterous forms the specific characters are in part
related to the plant structure which bears the gall; in the dip-
terous galls the specific characters are wholly related to the
specificity of the physiological phenomena associated with
the species of larvae concerned in the development of the
galls.

4. In the prosoplasmas the types of cells found are closely
comparable to those of the normal plant parts, but the tissue
forms discovered are fundamentally new; no analogous structure
forms are to be found in the tissues of the normal plant or its
allies.

5. In the dipterous prosoplasmas, since the gall's specific
tissue form characters are related to the species of insect, we
have the unique case of the "overlapping" of the hereditary
constitution of an animal on that of a plant in the sense that
factors associated with the insect determine the form character
locally, rather than those normally associated with the plant's
germ plasm. These latter plant factors suffer suppression.

6. It is suggested that in the field of zoocecidology we
probably have a unique place, heretofore unrecognized, to
attack the problem pertaining to the mechanism used in the
expression of hereditary characters.

May, 101 G] Morphology of the Zoocecidia of Celtis 287

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Parasites belonging to the Eriophyidae and tlie Itonididae (Cecidomyiidae)
Ohio Jour. Sci. 16:37-57. 2 pis. 1915.

EXPLANATION OF PLATES.
(See also table of abbreviations following.)

Plate XII.

Fig. A. Cross section of normal one year old stem of Celtis occidentalis in winter

condition. X 170.
Fig. B. Longitudinal section of one year old stem. X 170.
Fig. C. Section of normal leaf blade. X 180.
Fig. Ca. Study of leaf vein. X 190.

Plate XIII.

Fig. 1. Simple gall of Eriophyes sp. causing witches-broom, showing a common
mode of early development at one of the nodes. 1 yr. old. X 1.

Fig. la. Longitudinal section through base of gall branch. X IJ^.

Fig. lb. Sketch of 2 yr. old "broom" showing relation of secondary gall branches
to the primary ones. Tlie bark has been removed. X IH-

Fig. Ic. Detail study of part indicated at c, Fig. la. X 120.

Fig. Id. Study of trachea and adjoining cells indicated in Fig. Ic. X 400.

Fig. 2. Sketch of smooth specimen of lepidopterous twig gall. X \]/2-

Fig. 2a. Longitudinal section of gall shown in Fig. 2. X IH-

Fig. 2b. Diagram of normal stem section (transverse). X 18.

Fig. 2c. Diagram of gall section (transverse). X 18.

Fig. 2d. Detail study part d, Fig. 2c. X 150.

Fig. 3. Median section through gall of Pachypsylla vesiculum. (diagrammatic).
X 20.

Fig. 3a. Detailed study of part indicated at a, Fig. 3. X 100.

Plate XIV.

Fig. 4. Gall of Pachyps^dla sp. on side of stem. See also PI. XIX, Fig 10. X 5.

Fig. 4a. Diagram of cross section of gall and stem. X 22.

Fig. 4b. Detail of part i), Fig. 4a. X 100.

Fig. 4c. Detail of part c, Fig. 4a. X 100.

Fig. 4d. Detail of part d, Fig. 4a. X 380.

Fig. 5. Gall of Pachypsylla gemma. X 5.

Fig. 5a. Diagram of transverse section of P. gemma. X 22.

Fig. 5b. Detail of part b, Fig. 5a. X 150.

Fig. 5c. Normal bud. X 5.

May, 1916] Morphology of the Zoocecidia of Celtis 289

Plate XV.

. Fig. 6. Gall of Pachypsylla mamma (mature). X 4.
Fig. 6a. Vertical median section through mature gall. X 4.

Fig. 6b. Diagram of a slightly immature specimen. Median, vertical section. X 36.
Fig. 6c. Detail of part c, Fig. 6b. X 85.
Fig. 6d. Detail of part d, Fig. 6b. X 85.
Fig. 6e. Detail of part near e, Fig. 6b. X 85.
Fig. 6f. Normal leaf cystolith at f, Fig. 6b. X 340.
Fig. 6g. Aborted cystolith at g, Fig. 6b. X 340.
Fig. 6h. Detail study of nutritive tissue close to blind end of apical canal, showing

criss-cross thickening of cell walls. X 125.
Fig. 6i. Parenchyma and scleride cells from mature gall. X 85.
Fig. 6k. Parenchyma from leaf mesophyll. X 85.
Fig. 6m. Parenchyma from petiole cortex before thickening. X 85.
Fig. 6n. Parenchyma from twig pith. X 85.

Plate XVI.

Fig. 7. Gall of Pachypsylla venusta. X 1J^2-

Fig. 7a. Longitudinal median section of P. venusta. X IJ^.

Fig. 7b. Tangential section of gall, showing flocculent waxy material developed

by the nymphs of P. venusta. X IJ^.
Fig. 7c. Transverse section of gall. X lYi-

Fig. 7d. Detail of outer part of wall indicated at d, in enlargement near 7c. X 100.
Fig. 7e. Detail of inner part of wall indicated at e near Fig. 7c. X 100.
Fig. 7f. Lignified cell with simple pits illustrating the type of cell comprising the

core of the gall. X 400.
Fig. 7g. Multicellular trichomes lining the canals leading into the chambers. See

g, Fig. 7a. X 100.
. Fig. D. Cross section of normal petiole. X 170.

Plate XVII.

Fig. 8. Gall of Cecidomyia unguicola. X 6.25.

Fig. 8a. Detail study of longitudinal, median section of gall. X 36.

Fig. 8b. Detail study of a transverse section of gall taken distal from the gall
base, about one-third the length of the gall. X 36.

Fig. 8c. Trichomes found in the apical canal. X 170.

Fig. 8d. Sclerenchyma and crystal-bearing cells found at proximal end of pro-
tective layer. X 340.

Fig. 8e. Sclerides of one year old stem adjoining bast fibres. X 340.

Fig. 8f . Sclerides of three year stem with associated crystal-bearing cells. X 340.

Fig. 9c. Sclerenchyma cells and crystal-bearing cells from proximal side pro-
tective layer of Phytophaga celtiphyllia (9a). X 340.

Figs. 10-lOa. Phytophaga wellsi. Gall and vertical median section of gall. X 4.1.

Figs. 11-lla. Cecidomyia sp. Gall and median section of gall. X 6.25.

Figs. 12-12a. Cecidomyia sp. Gall and median section of gall. X 4.1.

Figs. 13-13a. Cecidomyia sp. Gall and median section of gall. X 6.25.

Fig. 13b. Details of distal end of median section of gall 13. X 85.

Figs. 15-15a. Cecidomyia sp. Gall and median longitudinal section of gall. X 4.1.

Fig. 15b. Transverse section of gall 15. X 6.25.

Pl.\te XVIII.

Fig. 9. Gall of Phytophaga celtiphyllia. X 6.25.

Fig. 9a. Vertical median section of gall of Phvtophaga celtiphyllia .shown in

detail. X 36.
Fig. 9b. Details of cells found in region near b in Fig. 9a. X 140.
Figs. 14-14a. Cecidomyia sp. Gall and median section of gall. X 4.1.
Figs. 16-16a. Cecidomyia sp. Gall and median section of gall. X 6.25.

290

The Ohio Journal of Science [Vol. XVI, No. 7,

Plate XIX.

Fig. 1. Witches-broom. Gall technically confined to proximal ends of branches,

inconspicuous in the photograph. X M-
Fig. 2. Lepidopterous gall of lateral branch. X 1.
Fig. 3. Pachypsylla sp. Gall on side of twig. Gall broken open to show the nvmph.

X 4.
Fig. 4. Cecidomyia sp. Gall Xo. 16. An old gall whose chamber was not dropped.

X3H.
Fig. 5. Cecidomyia sp. Immature galls of No. 16 on fruit. The side of the berry

has been removed to show the galls projecting into the ovulary cavity, the

ovule in which remains aborted. X 2.
Fig. 6. Cecidomyia sp. Mature galls (No. 16) on twigs. Upper galls at stage in

which the larval chambers are dropped: lower gall older, the tissue dying

and turning black. X 3.
Fig. 7. Galls of Pachypsylla venusta. (gall of petiole). X 14-
Fig. 8. Cecidomyia sp. Immature galls (No. 16) on fruit. Normal fruit shown

near it. X 1?4.
Fig. 9. Galls of Pachypsylla mamma. X M-
Fig. 10. Galls of Pachypsylla gemma (bud galls) and those of Pachypsylla sp.

forming ovoid lateral stem swellings. X J4.

TABLE OF ABBREVIATIONS.

abc. 1. — abscission layer.
ab. xy. — abnormal xylem.
ab't. cys. — aborted cystolith.
ap. c. tr'm. — apical canal trichomes.
ba.- — bast.

bn. sh. — bundle sheath.
ca. — cambium,
ck. — cork,
cor. — cortex.

cor. par. — cortical parenchyma,
cys. — cystolith.
cry. s. — crystal "sac."
cu. — cutin.

deh. 1. — dehiscence layer.
diff. p. — differentiated pith,
epi. — epidermis.
g. cor. — gall cortex,
hyp'l. mes. — hyperplasied mesophyll.
hyp'l. ph'g. — hyperplasied phellogen.
hyp't. pal. — hypertrophied palisade tis-
sue,
la. — larva.
1. c. — larval chamber.

1. V. — leaf vein.

lig. scl. — lignified sclerenchyma.

med. r. — medullary ray.

m. la. — middle lamella.

nut. 1. — nutritive layer.

nym. — nymph.

p. — pith.

pal. par. — palisade parenchyma.

ph. — phloem.

ph'd. — phelloderm.

ph'g. — phellogen.

pr. xy. — primary xylem.

pro. 1. — protective layer.

scl'd — scleride.

scl'd. 1. — scleride layer.

sim. p. — simple pit.

sp. par. — spongy parenchyma.

s. V. — sieve vessel.

tr'a. — trachea.

tr'd. — tracheid.

w. par. — wood parenchyma.

xy. — xylem.

Ohio Journal of .Science.

Vol. XVI, Plate XII.

Beitiam IV. Ifelh

■Ohio Journal of Science.

VOL. XVI, Plate XIII.

£erlram W. Wells

Ohio Journal of Science.

Vol. XVI, Plate XIV.

Bertram W. Wells

Ohio Jocrxal of Science.

Vol. XVI, Pr..ATE XV,

Bertram IT. Wells

Ohio Journal of Sciknce.

Vol. XVI, Plate XVI.

Bertram If. IVells

Ohio Jourxal of Science.

Vol. XVI, Plate XVII.

lii-rtravi IV. IVells

Ohio Journal of Science.

Vol. XVI, Pl.\te XVIII.

Ohio Jodrxal of Science.

Vol. XVI, PL.A.TE XIX.

Per ham \V. Wells

HOMOPTEROUS STUDIES. PART II.

Morphological Studies of the Superfamily Jassoidea.

Eric. S. Cogan, M. A.

Introduction.

The Superfamily Jassoidea comprises a large number of
small or comparatively small Homopterous insects, which
agree in respect to the character of the hind tibiae. The latter
are prismatic in shape and are armed with a row of spines on
their posterior margins. The head varies in shape and may
be angular or rounded, produced or shortened. The eyes are
located on the lateral margins of the head, and the breadth
across them is frequently the widest part of the body. The
antennas are usually inserted on the face between the eyes.
The thorax varies considerably, but in all the pronotum is the
most pronounced region. There are two pairs of wings, the first
pair being developed as tegmina and are usually coriaceous,
while the second pair may be membranous. In some forms the
elytra are reduced in size.

The superfamily is generally subdivided into four sub-
families, viz. : Bythoscopidas, Tettigoniellidce, Jassidas and
Typhlocybidee, the subdivision of the first three being based
on the location of the ocelli, and of the last, on the character
of the venation of the elytra. In the Bythoscopidae, the
ocelli are situated on the front below the border of the vertex;
in the Tettigoniellidas they are on the disk of the vertex, while
in the Jassidae they are to be found on the border of the vertex
or between the latter and the face. In the three subfamilies
mentioned, the elytral nervures fork on the disk, while in the
Typhlocybidse the nervures fork at the base and run to the
apex of the elytron without further dividing. Again in the last
named family the ocelli may or may not be present. The
various subfamilies are further subdivided into a number of
genera, and frequently into tribes and divisions.

The chief object of this investigation has been to obtain a
definite understanding of the external and internal anatomy
for the group generally and to establish homologies with the

299

300 The Ohio Journal of Science [Vol. XVI, No. 7,

other Homopterous families. Very little work has been done
on the anatomy of the Jassids, and as far as the writer is aware,
no complete treatment of any phase of the morphology has yet
been offered. Considerable work has been accomplished on
the other Auchenorrhynchous families by Muir, Kershaw,
Licent, Pantel, Bugnion, Sulc and others, but the only treat-
ment of the Jassoid anatomy is to be found in the general dis-
cussions of systematic works on the group. Thus the works of
Signoret, Burmeister, Flor, and Melichar contain general
discussions of the external anatomy, which are necessary for
taxonomic purposes. The wings and their structure have been
ably treated by Metcalf, and only mention will here be made
of this phase.

Since the only work on the external anatomy of the Jassoidea
has been done by systematists and for taxonomic purposes,
Professor Osborn suggested to the writer that an investigation
into the morphology of the group would be of some avail, and
accordingly the work was undertaken. The scope of the inves-
tigation is confined to the four families. A common and seem-
ingly generalized species was selected from each family and in
the main the studies here noted were conducted on these. For
the Bythoscopidae, Agallia sanguinolenta was selected chiefly
because the material, both adult and nymph, was abundant
and readily obtainable; the same may be said of Draecula-
cephala mollipes for the Tettigoniellidas, Deltocephalus inimicus
for the Jassidee, and Empoasca mali for the Typhlocybidae.
In many cases species belonging to other genera were studied
and compared with the above where such was necessary.
To Professor Osborn the writer wishes to express his indebted-
ness for directing the investigation, and for helpful criticism
and suggestion.

Methods.

The material for gross dissection was killed and preserved
in a 4 per cent, solution of Formalin and found to be quite
satisfactory. Some specimens were killed in hot water and
preserved in 70 per cent, alcohol. In many cases material
which had recently been collected in the field was killed in 100
per cent, alcohol and dissected and examined immediately.
All dissection was accomplished by means of a Bausch and Lomb
binocular microscope. For the dissection of the smaller

May, 191G] Homopteroiis Studies. Part II 301

insects, a shallow dissecting pan made by filling a watch glass
with paraffin, proved very convenient. The study of many of
the chitinized parts was facilitated by previously boiling the
specimens in a 10 per cent, solution of potassium hydroxide,
washing in water and examining in glycerine or alcohol. The
former proved very suitable, and has the advantage in that it
evaporates very slowly. In the dissection of the reproductive
organs and the digestive apparatus, normal salt solution was
used to float out the organs. Some of the immature forms
were conveniently studied by simply killing in Xylol and mount-
ing in balsam almost immediately. Certain structures, such
as the tracheal system, show up clearly when treated by this
method.

Material for sectioning was killed mainly by two methods.
Hot water was used where the insect has recently moulted
and the chitin had not yet hardened. Carnoy A (Glacial
acetic acid one part, to absolute alcohol three parts) proved
to be a very good fixing fluid. Practically all the material
for sectioning was killed by this method. Delafields haema-
toxylin and eosin were the stains used for staining sectioned
material. Staining in toto did not prove satisfactory. Picric
acid for staining chitin was used to some extent. The material
was embedded and cut in paraffin with a melting point of bh C.

THE HEAD.

External Anatomy. (PL XXI, XXII, Figs. 1, 2, 3, 4, 5, 7, 25-31).
The different regions of the Jassoid head have been well
defined by systematists in the group and before proceeding
to a discussion of the structure, it will be as well to outline
these regions, which now, for the most part, are of interest
because of their place in the taxonomy of the superfamily.
The dorsal region, i. e., the portion of the head between the
compound eyes is termed the vertex (v), and in some of the
families it bears the paired ocelli (o). Although not a definite
sclerite, it serves as a good "landmark" for descriptive purposes.
The region from the anterior edge of the vertex to the first
apparent transverse "suture" is regarded as the front ("frons") ;
its lateral margins are limited by the longitudinal sutures which
run from the antero-lateral edges almost to the antennae and
frequently to the anterior edge of the head. Attached to the

302 The Ohio Journal of Science [Vol. XVI, No. 7,

anterior edge of the frons is the broadly rectangular clypeus,
and at the distal edge of the latter is seen the small peglike
labrum. At the sides of the frons and clypeus, two small
semi-circular plates are seen, these are the lorse. The genae
are the large regions extending from beneath the eyes to the
anterior edge of the clypeus and completely surrounding
the lor£e. The rostrum or beak projects from under the surface
of the clypeus and encloses the setae. The head is greatly
deflexed with the result that the rostrum lies between the
anterior coxae and projects in a caudal direction.

The same regions as are seen in the Jassoid head are to be
differentiated in the Cicada, or any other of the Auchenor-
rhynchous Homoptera. In 1896 Marlatt drew attention to
the fact that the frons of Cicada septendecim was really the
clypeus, that the clypeus and labrum constituted the labrum,
and that the lorae were the external representatives of the
mandibles, while the genae were the corresponding pieces of
the maxillae. No attempt was made to homologise the various
parts, until the work of Muir and Kershaw appeared in 1911.
From a study of the external and internal anatomy as well as the
development and embryology of both Homopterous and Het-
eropterous forms, these authors concluded that the "frons
of many writers was the clypeus, and their clypeus was the
labrum. The lorae have no connection with the mandibles,
but are lateral developments of the clypeal region. The dorsal
and outer pair of setae are the mandibles, developed direct from
the first pair of appendages behind the stomodaeum of the
embryo, and articulated in their normal position, viz., on the
oral margin between the clypeus and the maxillae. The ventral
and inner pair of the setae are part of the maxillae developed
directly from the distal joint of the second pair of appendages
behind the stomodaeum of the embryo, the basal joint being
directly developed into the maxillary plate." In a paper on
the Development of the Mouthparts in Homoptera, the same
authors conclude that "(1) The mandibles and maxilla arise
as in other insects, the former being articulated in an approxi-
mately normal position. (2) The Homopteran and Heterop-
teran mouthparts arise and develop in the same manner.
(3) There is no mandibular plate. (4) The tentorium agrees
essentially with that of other insects. (5) The maxillary
seta does not represent the palpus, but may be a development

May, 1916] Homopterous Studies. Part II 303

of the palpifer or the combined lacinia and galea. (6) The
maxillary-plate represents the cardo and stipes." In their
discussion of the Homology of the Hemipterous mouthparts,
no reference is made to the Jassoidea, except that the Tetti-
goniellids can be easily homologised with the Cicada. Beyond
this reference to the Jassoid head the writer has been unable
to find further treatment of the subject.

In the following discussion of the Jassoid head, the fixed
parts will be considered first and then the free or movable
parts.

Fixed Parts of the Head. (PL XX, Figs. 1, 2, 3, 4, 5).

The Jassoidea agree with the other Hemipterous families
in the general arrangement of the head and mouthparts. The
head is greatly deflexed and the mouthparts are attached to the
caudo-ventral portion of the capsule, with the result that the
beak or so-called proboscis is directed caudally between the
first pair of thoracic legs.

Head-Capsule. — As in a generalised insect, the head of the
Jassid is composed of a number of sclerites, which have become
united to form the head-capsule, and this becomes the external
skeleton of the head. To this capsule, the various appendages
of the head are attached and articulated. In the head it will
be found that no trace of the primitive sclerites forming the
head-capsule is to be found, for they have either disappeared
or amalgamated with other sclerites. The various regions on
the Jassoid head were indicated before, and only those areas
which can be definitely recognized as sclerites will be considered
here.

The dorsal region (v) of the head (i. e., the vertex) is not
separable from the front or frons (Fr), and there is no trace of a
suture between them, as one would expect. Together with
the genffi and occiput, the vertex and front constitute the
epicranium.

The vertex (v) varies considerably in size from a mere narrow
region in the Bythoscopidse to a greatly elongated area in the
Tettigoniellids (especially in the Tribe Dorydini). It usually
bears the paired ocelli (o) ; thus in the Family Tettigoniellidag
they are located on the disk or surface, in the Jassidse on the
cephalo-lateral margin near the eyes, and in the Typhlocybidae
(when present) also on the cephalo-lateral margin. But in

304 The Ohio Journal of Science [Vol. XVI, No. 7,

the case of the Bythoscopidae they have been carried over
and down on the face, while the dorsal surface of the vertex
is greatly reduced.

The Front, although a true sclerite, is not readily differ-
entiated from the following sclerite — the clypeus (clyp.) — the
suture between them being obsolete, but its position can be
judged by the fact that the anterior arms (i. a.) of the tentorium
are invaginated on each side, where the suture should normally
end. The front usually, at least in the more generalized insects,
can be identified owing to the fact that it bears the median
ocellus, but no trace of such an ocellus is to be found in the
Jassid head. The frontal region ("frontal ridge") then would
be the area between the cephalic margin of the head and a
transverse line connecting the invaginations of the anterior
arms of the tentorium. In the Jassoid head these invaginations
occur at the cephalic end of the maxillary suture, on the so-called
mandibular plates or lorae. Its lateral margins would be
defined by the longitudinal sutures on either side of the head.

The clypeus (clyp.) is the sclerite attached to the frons
along its anterior margin. In the Jassid head as in other
Homoptera, it is not easily distinguished from the front; it
is a broadly rectangular sclerite, generally somewhat convex
with its lateral margins developed into two plates (lorae) which
attach along the sides of the labrum. These two plates (the
lorae or so-called mandibular plates) have long been regarded
as the external pieces of the mandible, although in reality they
have no connection with the mandibles. Muir and Kershaw
have shown conclusively in their work on the development of
the mouthparts of the Homoptera, that the mandibles become
enclosed within the head in the course of development. No
true suture exists where these two plates are in relation to the
labrum, but their basal portion is attached strongly to the middle
piece of the clypeus. If we consider the mesal piece as the clypeus
proper, then the lateral developments might be regarded as
the antecoxal pieces of the mandible.

The labrum (labr.) is the upper lip and is attached to the
anterior margin of the clypeus. It constitutes the roof of
the mouth and is differentiated with difficulty from the clypeus.
However the anterior margin of the clypeus is connected with the
pharynx by two small developments of the tentorium, and these

May, 1916] IIo7nopterous Studies. Part II 305

mark the region where labrum and clypeus meet. The shape of
the labrum is broadly rectangular, with the anterior margin
generally rounded off, and forming a covering for the basal
joint of the labium. Projecting from under its anterior margin
and fitting into the groove at the base of the labium is the small,
peglike epipharynx (epi.). On an external view the epipharynx
appears as part of the labrum, but on close examination it will be
seen to run back as the dorsal wall of the pharynx.

The Occiput or the posterior part of the dorsal surface of
the head can not be differentiated from the vertex. However,
by viewing the head in its caudal aspect it may be seen as the
large sclerite surrounding the occipital forearm. Attached to
the ventral surface of the occiput, is the gula or gular region,
which is very small in the Jassoid head, owing to the deflection.
The gula consists of a small membrane attached at one end
to the base of the occiput and at the other to the basal joint
of the labium.

The Genas proper cannot be distinguished from the maxillary
plates — an amalgamation of the two sclerites taking place
early in the development of the insect's head. No trace of a
suture is to be found and we can only refer to the gen^ in
general terms as that region surrounding the compound eyes
on either side of the face and attached to the maxillary plates,
for the greater part.

Ocelli. — The ocelli (o) where present are two in number.
As stated before, in the Tettigoniellidae (Fig. 5), they are
located on the mid-dorsal surface of the vertex, while in the
Bythoscopidse they are situated on the face (Fig. 3). The
position in the case of the last named family is probably owing
to development of the epicranium, which occupies the greater
part of the dorsal region of the face. However, in the Jassidae
and TyphlocybidcC (where present), the ocelli are located on
the cephalo-lateral margins of the head. On examining the
internal structure of the head, it will be found that branches
of the dorsal arms of the tentorium proceed to the head just
beneath the ocelli. This was found to be the case in practically
all the forms examined. The ocelli are small, clear, circular
or oval structures, which are generally raised above the general
level of the head. Frequently they are colorless or glassy,
but in some cases they are pigmented with red or black.

306 The Ohio Journal of Science [Vol. XVI, No. 7,

Compound Eyes — The compound eyes (E) occupy the
greater part of the dorsal aspect of the head at the sides of the
vertex. They are large oval or semicircular bodies, which
extend back to the anterior margin of the pronotum. In the
immature forms they are relatively larger than in the adult
and are more rounded. The character of the facets is the
same as that of a generalised insect, although the number of
these facets is exceedingly great.

Movable Parts of the Head. (PI. XX, XXI, Figs. 6,7,13,16,17).
Antennos (Figs 18-21). — The antennae (A) are for the most
part setaceous in form ; structurally there is very little difference
between the morphology of the antennae in the various forms,
although it will seem as well to indicate here the more important
of these. The number of segments or joints varies considerably
and frequently cannot be distinguished at the distal ends. The
basal segment and those adjoining it are the most modified
in size. In the males of Idiocerus (Bythoscopid^) the distal
joints of the antennae are developed into small oval plates,
which Hansen has regarded as sensory structures. In many
of the Tettigoniellids and Jassids, small hairs or spines are
developed on the basal joints of the antennae. The antenna
of Deltocephalus inimicus figured shows this structure (Fig. 19).
These spines may have some sensory function, although no
trace of sense cones were found on them. The antenna are
inserted on the face between the compound eyes and the
longitudinal suture of the front. In some cases the point of
insertion may be a deep cavity, in others it may be shallow. In
some of the Bythoscopidae the cavity is overlapped by a distinct
ledge.

Labium — (PI. XX, Figs. 9, 13). The beak or proboscis of
the Jassid mouthpart is the labium or lower lip. It is relatively
short and thick, circular in outline, and is three-jointed. The
distal joint, or tip of the labium is the largest, the proximal
the smallest and the middle is about intermediate in size
between the two. Externally the labium appears to emerge
from under the labrum, but a closer examination w411 reveal
the fact that the tip of the epipharynx, a small, peg-like struc-
ture, which is attached to the anterior end of the labrum, fits
into a narrow groove on the surface of the labium and gives it
some means of support in one direction. Ventrally the labium

May, 1916] Homopteroiis Studies. Part II 307

is attached by its strong lateral and central muscles to the gula
and to the body of the tentorium. The membrane of the
proximal joint is developed into a central chitinous rod, to
which attach the central muscles (c) ; at the sides the muscles
attach directly to the basal joint at one end and to the gula
at the other. The labium forms the floor of the mouth, and
■encloses the mandibular and maxillary setae. As the mouth-
parts of the Jassid are fitted for sucking, the two pairs of setas
are in close relation in the trough which runs the full length
of the labium. This trough is shallow, and closed for the
greater part beyond the epipharynx. The maxillary setae
form the sucking tube through which the plant juices are
drawn. It is quite possible that the mandibles form the
piercing organs, by means of which the maxilla are enabled to
function. Two sets of muscles are to be found in the labium^
■circular (c. m.) and longitudinal. The longitudinal muscles
enable a back and forward movement, such as protrusion and
withdrawal, while the circular muscles allow of an up and
■down movement. The attachment of the labium to the gula
is not very strong and frequently on removing the head from the
body, the labium will remain attached to the anterior edge of
the prosternum. The setae are capable of withdrawal from the
trough of the labium, and may be free — this is often the case
in nymphal forms. At the anterior edge of the labrum where
the setae emerge from the head capsule into the labium, a small
membrane covers the entrance to the labium, making the
■structure airtight. This is necessary when it is considered
that the plant juices constituting the food of the insect must
be sucked up into the pharynx.

The tip of the labium is rounded and the setae are protruded
through a small hole at the end. The external region of the
labium is chitinized, and is set with numerous hairs or spines.
In feeding, the labium is applied to the plant leaf or tissue
and forms a guide for the setse. It however, does not enter
the plant tissue. It is quite possible that the close application
of the labium to the plant will render the connection airtight
so that the juices may more readily be sucked up.

Maxill(B~{V\. XX, Figs. 7, 17, 5, 4, 3). If the head of a
Jassid be examined, two large plates (mx. pi.) forming the
sides of the face and the lateral covering of the mouth, will be

308 The Ohio Journal of Science [Vol. XVI, No. 7,

found. These are the maxillary plates (mx. pi.), and they
occur in all Homoptera. Although the maxilla are fused with
the gense, they can be distinguished from the latter in that
they articulate with the maxillary set« (mx. s.), which are
enclosed within the head-capsule. The maxillary plates extend
around the sides of the face and constitute the border; they
completely surround the clypeus and meet anteriorly beneath
the labrum, where they are connected by a membrane. At the
sides the plates are turned down and under, forming the part
of the ventral surface of the head. Distally they turn back
on the under side of the head, and develop into two rectangular
chitinous plates — with which the maxillary setas articulate.
The maxillary setae are attached to these chitinous plates,
which in turn are hinged to the body of the tentorium (t. b.).

The maxillary setae (mx. s.) resemble the setae of other
Homoptera; they are long and slender for the most part, but
their proximal basal region is swollen, and attaches to a small
tendon (t.), which passes dorsally into the retractor muscles
(mx. r.) of the setae. A membrane sleeve surrounds the seta,
as far as the entrance to the labium. The strong protractor
muscles (mx. p.) of the maxillary setae are attached to the maxil-
lary plate, while the retractor muscles attach to the head-
capsule at the sides of the occiput. The articulation of the
seta is on the inner side of the maxillary plate and it can easily
be seen by reference to the figure (PI. I, Fig. 7) how the maxillae
can be worked forward and backward.

The exact homology of the maxilla in Homoptera is a ques-
tion on which no little discussion has arisen. The amalgamation
of the maxillary plate with the genee, would lead one to believe
at once that the whole of the plate at that side of the clypeus
constitutes the gena, but on examining the internal structure,
and the connection of the maxillary plate with the maxillary
seta, it can readily be seen that the maxillary seta is intimately
connected with the maxillary plate. Added to this the invagi-
nations of the posterior arms of the tentorium are to be found
at the sides of the occipital foramen, and are adjacent to the
attachment of the maxillary plates with their setas. In all the
insects so far examined, the invaginations of the posterior arms
of the tentorium have always been associated with the point
of attachment of the maxilla.

May, 1916] Ilomopteroiis Studies. Part II 309

Mandibles— (PI XX, Figs. 6, 16, 2, 4, 3). Viewing the head
on the inside from its caudal aspect, the two pairs of setae, viz.,
the mandibular (m. s.) and maxillary setae, can be seen attached
to the head capsule. These two pair of setse are in rather close
relationship, but with careful dissection it will be seen that the
more dorsal pair are articulated with head-capsule, between
the maxillary plate and the clypeus. The posterior end of the
mandible is produced into a small tendon (t) to which attach
the strong retractor muscles (m. r.) which attach in turn to
the head-capsule at the sides of the occipital foramen. A
small tendonous rod (m. a.) connects the mandibular seta with
the latero-posterior edge of the clypeus. While the mandibular
seta is intimately related to the maxillary seta in the labium,
the two are separate within the head-capsule. The mandibles
are capable of being withdrawn and protruded within limits
owing to the muscles, which are connected with the posterior
end. The retractor muscles (m. r.) attach to the head capsule
on the inner side of the clypeus. The position of the invagi-
nation of the anterior arms of the tentorium, which are asso-
ciated with the mandibles, enables one to homologise the
mandibular setae in the Jassoidea with the mandibles in the
Cicadidae and other Homoptera.

The identity of the mandibular plate or lora, has been well
demonstrated by the work of Muir and Kershaw on the develop-
ment of the Homopterous head, wherein it is shown that the
mandibles become completely enclosed within the head-capsule.
Although this question has been much discussed, from various
points of view, it seems to the writer clear that the evidence
favors the interpretation of the mandibular setae as representing
the entire mandible. The articulation of the mandibular
set^ viz., between the clypeus and the maxilla is the normal
position, and further the invagination of the anterior arms of
the tentorium add additional weight to the interpretation.

The structure and morphology of the mandibular seta
resembles very much that of the general Homopteron; the
tips are barbed, with the barbs (b. a.) pointing backward.
As stated before, their function is probably that of piercing
the plant, to enable the maxillae to perform the sucking function.
Like the maxillary, the mandibular setae are surrounded for
their proximal half with a membranous sleeve.

310 The Ohio Journal of Science [Vol. XVI, No. 7,

Internal Anatomy. (PI. XX, Figs. 2, 3, 4, 5, 8, 9, 10, 11; PI.

XXI, Fig. 22).

In the following discussion of the internal anatomy of the
head, those structures previously mentioned will be omitted
and only the parts which pertain directly to the internal
structure will be considered.

Tentorium — (Figs. 4, 5). In the heads of all insects there
is to be found a definite arrangement of supporting, chitinous
structures, which owe their origin to three pairs of primary
invaginations of the body wall. The structure itself consists
of a system of rod or plate-like bodies, which constitute the
tentorium or internal head skeleton. In the Jassid head this
skeleton is present, but in some respects it has been modified.
The three pairs of arms which compose the tentorium are known
respectively as the anterior, dorsal and posterior arms. The
anterior arms (i. a.) are invaginated on the cephalo-lateral
edges of the clypeus; in the Jassid head this invagination is to
be found at the upper corner of the so-called mandibular plate;
it persists as an opening and can be distinctly seen in a specimen
which has been boiled in KOH. In many insects the points
of the invaginations do not persist in the adult. The anterior
arms (i. a.) are always associated with the mandibles, and
in the Jassid head they are to be found near the articulation
of the mandibular setse. The dorsal arms (d. a.) are invaginated
beneath the antennee and are easily seen in the head of Delto-
cephalus inimicus or any Jassoid. They are always associated
with the antennae, and in this case they occupy their normal
position. While the invaginations themselves are not readily
seen, the arms are quite prominent. The posterior arms (i. p.)
are invaginated at the sides of the occipital foramen and are
near the attachment of the maxilla. The upper ends of the
posterior arms are connected by a chitinous bridge (the max-
illary bridge of Muir and Kershaw), which is the body of the
tentorium (t. b.). The latter divides the occipital foramen
into two parts.

In the Jassoid head the parts of the tentorium have been
modified to a certain extent, but nevertheless they can readily
be homologised with the corresponding structures in the Cicada
and other Homoptera. From the invagination of the anterior
arms, on either side of the head, two small chitinous structures

May, 1916] Homopterous Studies. Part II 311

run forward to the anterior edge of the clypeus; here they
attach to the dorsal region of the clypeus, and at the same time
are connected with one another by a narrow bridge, which is
scarcely visible. From the anterior region of the pharynx
two small tentorial structures attach to the anterior arms and
form the chief means of support of the pharynx.

The posterior arms, the invaginations of which are con-
nected by the body of the tentorium (t. b.), run forward along
the ventral region of the head, as far as the salivary pumping
apparatus (s. p.), where they attach on either side to the
syringe. The body of the tentorium is very prominent and
on either side it forms a means of support for the maxilla, to
which it is attached. Its median portion supports various
muscles, including those of the salivary pump and the labium.
Passing up from the invagination, the posterior arms nearly
surround the occipital foramen and join with the corresponding-
dorsal arms. The connection is not so very prominent, and in
all the forms examined, the junction was confined to a mere
tendon. The dorsal arms, which are to be found beneath the
antennae, are quite prominent in the dorsal region of the head.
The size of the dorsal arms varies somewhat in different species ;
in Draculecephala mollipes they are short and branched, while
in Deltocephalus inimicus and Agallia sanguinolenta they
are much longer. Between the invaginations of the dorsal
and anterior arms, small tendonous plates are to be seen.

In the Jassoid head, the correlation between the tentorial
structures and the appendages of the head is to be found and
forms the basis for their interpretation.

Epipharynx—{Pl XX, Figs. 14, 1, 2, 3, 15). The anterior
end of the dorsal plate of the pharynx is differentiated into
the epipharynx (ep.), which is seen externally as the small peg
covering the base of the labium. This structure is closely
related to the labrum and in fact, the separation of the two
is a difficult matter. The pharynx (ph.) continues along the
under side of the labrum and passes out as the epipharynx.
The epipharynx is fused with the anterior edge of the labrum,
but a trace of the former condition can be seen.

Hypopharynx — (PI. XX, Figs. 8, 15). The anterior end
of the ventral plate of the pharynx is the hypopharynx (hyp.)
and is a prominent structure in the mouth-cone of the Jassid..

312 The Ohio Journal of Science [Vol. XVI, No. 7,

It is broadly spoon-shaped, with the anterior end slightly
pointed. Beneath it, the salivary pumping apparatus (s. p.)
occurs and is in close relationship with its lower surface. The
hypopharynx is heavily chitinized. The opening of the pharynx
into the suction canal of the labium is surrounded by hypo-
dermis, which encloses the setae.

Pharynx — (PI. XX, Fig. 5). The chitinous pharynx, as in
all Hemiptera, constitutes a pumping apparatus, by means
of which plant juices and other food are withdrawn into the
digestive canal. The pharynx is a comparatively short,
simple, chitinous tube, supported by strong muscles. The
dorsal plate is somewhat elastic, and is capable of being with-
drawn from the ventral plate by the pharyngeal muscles
(ph. m.), which attach to the head-capsule along the inner
surface of the clypeus. Apparently the pharynx is about the
most powerful organ of the head, as the preponderance of
pharyngeal muscles is obvious. The pharynx passes back
over the body of the tentorium into the membranous esophagus.

The Salivary Pumping Apparatus — (PL XX, Figs. 8, 15).
This characteristic Hemipterous structure is to be found beneath
the base of the hypopharynx. It consists essentially of a broad
spoon-shaped structure, into which fits the plunger (p.) ; the
latter is slightly smaller than the spoon or barrel (b. a.) and
functions as the driver of the apparatus. The plunger is
developed backward into a thick rod (r.), to which attaches
at its end the protractor muscles (p. p. s.). The united salivary
ducts (s. d.) open into the base of the barrel, and by the forward
motion of the plunger the saliva is forced forward through a
small canal (s. d. h.), which leads to the anterior edge of the
hypopharynx. At their entrance to the barrel the salivary
ducts are chitinized. The protractor muscles (p. p. s.) of the
plunger rod attach to the body of the tentorium, while the
retractor muscles (p. r. s.) attach on the under side of the rod
at one end and to the maxillary plates at the other. The
plunger is thus capable of a forward and backward motion,
by which means the saliva is pumped into the canal.

Salivary Glands — (PL XXI, Fig. 22). In the Jassoid head
four separate salivary ducts are to be found; two pairs unite
behind the salivary pump into one common duct, but farther
back they separate into two pairs, which continue along the

May, 1916] Honiopterous Studies. Part II 313

floor of the mouth into the thorax. Both pairs of ducts end
in glands, which are long structures, normally located in the
abdomen. Each gland is whitish, and rather narrow. The
salivary glands secrets the saliva which is carried forward into
the pump and thence into the sucking tube.

THE THORAX.

The structure of the thorax was not studied in any degree
of detail, and only reference to the more striking features will
here be made. As in a generalised insect the thorax is composed
of three segments, in order, the pro-, meso- and meta-thorax.
The prothorax has undergone considerable modification and
the traces of the sclerites seem to have been entirely lost.
The dorsum or tergum is the large piece on the dorsal surface;
it overlaps the mesonotum. Laterally the prothorax shows
little differentiation into episternum and epimeron. The
sternal region is reduced to a small piece, which bears the small
chitinous apophyses. At the sides the first pair of legs are
borne. The mesothorax is large and well developed, com-
prising a number of sclerites, which are separated with difficulty.
Laterally it bears the tegmina and beneath the second pair of
legs. The episternum and epimeron are easily recognised in
this segment. A noticeable feature of the mesothorax is the
great development of the musculature; the large wing muscles
are very prominent. The apophyses are strongly developed.
The metathorax is striking because of the great development
in size of the hind coxas ; the latter are supported by very strong
muscles. The sternal surface of the metathorax is almost
completely overshadowed by the large coxee.

THE ABDOMEN.

The Jassid abdomen is composed of at least eight segments,
of which the first seven bear spiracles. Each abdominal
segment is composed of a dorsal tergite and a ventral sternite,
the two being connected by pleural membranes.

The modification of the posterior end of the abdomen for
reproductive purposes has brought about a reduction in the
number of apparent segments and many of these are recognised
with difficulty. In the female the last abdominal segment is
known as the pygofer (pyg.) ; through its dorsal region the anal

o

14 The Ohio Journal of Science [Vol. XVI, No.

tube (an. t.) opens to the exterior. The ventral portion almost
completely encloses the ovipositor (ovp.) which is generally
a long, rather slender, heavily chitinized organ, hinged to the
caudal end of the preceding segment. In its simplest form the
ovipositor consists of two strong ventral valves (v. v.), which
on being spread apart, expose the two inner valves (i. v.). The
latter constitute the main part of the ovipositor and are small,
sharp, slender pieces, which fit close together and so form a
channel through which the ova may be extruded. The tip
of the inner valves are barbed or sickle-shaped. The vagina
opens into the anterior end of the channel. Beneath the inner
valves are two large pieces which fit close together and compose
the dorsal valves of the ovipositor, (d. v.).

The posterior region of the female abdomen as well as that
of the male, shows a great deal of variation in the modification
and advantage is taken of this for taxonomic purposes. The
ventral abdominal segment just anterior to the ovipositor
frequently shows a great deal of variation in shape. In the
majority of the forms examined, however, the essential details
of the female genital armature do not differ strikingly from the
above.

In the male the last dorsal segment is known as the pygofer,
and as in the female, the anal tube opens on it. Ventrally, the
posterior of the abdomen is modified into a series of plates which
afford protection for the penis. The uppermost of these plates
is connected with the preceding abdominal segment and con-
stitutes the valve (g. v.) ; it is generally triangular in shape, and
extends about half way over the plates beneath. The latter are
the genital plates (g. pi.) and are two long, somewhat rectangular
pieces, which cover over the penis and penis guides. The
genital plates vary considerably in size and shape, and advantage
is taken of this character in the differentiation of species. In
copulation the ventral valve bends down so as to allow the
genital plates to spread apart, and the penis, with its accompany-
ing guides is brought into action. The penis (pen.) is an elongate
slender structure, which is strongly chitinized. It is hinged
at the base of the j^ygofer, and is capable of considerable motion
in a ventral direction.

May, 1916] Homopteroiis Studies. Part II 315

Internal Anatomy.

The Digestive System. (PI. XXI, Fig. 22; PI. XXII, Fig. 34).

The chitinous pharynx passes back into the membranous
esophagus (e. s.), which is a relatively short simple tube.
In the metathorax, where the esophagus enters the midintestine,
a constriction is noticed and a large food reservoir is developed.
The latter structure is comparable to the food-reservoir of
certain Fulgoridas and Cercopidae. The food-reservoir is a
bilobed or double U-shaped structure, which opens into the
intestinal coils; its function is probably that of a storage reser-
voir. From the reservoir the alimentary canal continues as a
long, convoluted tube (m. i.) of small diameter; the length of
midintestine is about two and a half times that of the body.
It ends in the short rectum without differentiating into either
colon or ileum. The rectum continues to the anus, which is
located on the dorsal surface of the last abdominal segment.

Opening into the midintestine (m. i.) are the long Malpighian
tubules (mp. t.) ; these are difficult to detect in the Jassid, but
at length may be seen among the coils of the intestine. They
are about the same length as the body and are of small diameter.
There are only two pairs so far as was observed.

The food reservoir (f. res.), or crop, in Deltocephalus
inimicus occurs entirely within the abdomen and does not enter
the thorax. This seems to be the general condition, although
in some forms it is to be found penetrating the thoracic region
In some forms it occupies a great part of the anterior region
of the abdominal cavity.

The digestive system may be readily dissected out of
preserved specimens, although some little difficulty is exper-
ienced in keeping the coils , of the intestine intact. It was
noticed that in specimens which had been cleared in carbol-
turpentine, there w^as a tendency on the part of the food
reservoir to swell up and telescope through the dorsal wall of the
abdomen.

The opening of the alimentary canal to the exterior, i. e.,
at the anus, is on the last abdominal segment and in the majority
of individuals examined it was noticed that the anal orifice was
beset with hairs and strong spines. The anal tube is a small
structure, which is heavily chitinized. It conveys the feces to
the exterior. In most individuals the anal tube is two-jointed,
the basal joint being the longest.

31G The Ohio Journal of Science [Vol. XVI, No. 7,

Tracheal System. (PL XXII, Fig. 33).

The Tracheal System consists of the main trunk (m. t.)
system connected with the spiracles (spi.). There are in most
forms nine pairs of spiracles; two thoracic, and seven abdominal
(I-VII), although in some species the abdominal number may
be only six. The thoracic spiracles (t. spi.) are at first rather
difficult to detect, but may be found below the wings on the
episterna as two small, unprotected holes. On the abdomen
the spiracles (ab. spi.) appear as small, elongate, narrow holes,
located on the anterior halves of the segments, near the pleural
membranes. Each spiracle connects with the main trunk
system by a short tube.

The main trunk system (m. t.) comprises the two lateral
tubes, which run down the sides of the body and anastomose.
The two longitudinal trunks are connected by transverse
trachea in the meso- and meta-thorax. The anastomosis in
the thoracic trachea is best shown by reference to the Figure
(PI. XXII, Fig. 33). Two large transverse tubes connect the
longitudinal trunks in the mesothorax, while in the metathorax
the two transverse tubes do not open directly into the main
trunks, but connect with the spiracle tube. A small tracheal
tube runs between the two thoracic spiracles and gives off the
branches which run to the wings. In the nymphs these tubes
are very evident, although in the adult they are not so prom-
inent. At the caudal end of the body the two trunks are in
close relationship by means of their smaller branches, but no
distinct tracheal connection is seen.

From the main longitudinal trunks arise the three systems
of branches, the dorsal, visceral and ventral, which ramify
through each segment, and portion of the body. Two strong
branches are seen in the head, and supply the antennae, mouth-
parts and the viscera of the head with trachea. Branches
of the dorsal system can frequently be found in the dorsal
muscles of the thorax, and in the peripheral region of the dorsum.
The visceral system of branches supports the digestive apparatus
and the reproductive organs, while the ventral system is closely
connected with the nervous system and the ventral musculature.

May, 1916] Homopterous Studies. Part II 317

Reproductive System. (PL XXII, Figs. 35, 36).

Female Organs — The paired ovaries (ov.), are normally
located in the third segment of the abdomen, but frequently
they occupy the greater portion of the abdominal cavity.
Each ovary consists of six ovarian tubes (o. t.) or tubules,
although this number is subject to some variation. Holmgren,
who has studied the female organs in some detail gives the num-
ber of ovarian tubules in a Thamnotettix as twelve or two
pairs of six each. Each ovarian tube (o. t.) is attached at a
common point to the suspensor (sus), which in turn is supported
by a tracheal branch in the dorsal region of the body. The length
of the ovarian tubule varies greatly, but it frequently exceeds
the abdomen; in many cases, as just before oviposition, the
abdomen will be greatly distended by the numbers of eggs
in the ovaries and on first examination it would seem that the
whole abdominal cavity was filled with ova. In some cases the
ovarian tubes may be pressed into the thoracic region, previous
to oviposition. All the ovarian tubes unite caudally in a
common oviduct (Ovd.) which is short and broad, although in
some forms e. g. Cicadula, it may be long. The oviduct is
frequently constricted before the opening of the receptaculum
seminorum (rec. sem.) which is a semi-circular structure,
lying to the side of the oviduct. The size of the receptaculum
seminorum varies and may be large or small. Beyond the
receptaculum seminorum the oviduct receives two pairs of
accessory glands (ag\ ag-), which are very long and extend
back into the abdomen. The vagina which is the terminal
portion of the oviduct, opens into the ovipositor, through
which the ova are extruded.

Male Organs — (PI. XXII, Fig. 35). In the male each testis
is composed of a varying number (usually six) follicles (f.). The
testes which are located at the posterior end of the abdomen are
yellowish in color, and are frequently enclosed in a whitish
membrane. Each follicle is about three times as long as broad,
and opens into the vas deferens (v. d.) by a separate duct.
The vasa deferentia are about four times as long as broad
and unite to form the ejaculatory duct (e. d.), which is merely
a dilation before the penis or copulatory organ. Small accessory
glands (a. g.) enter the vasa deferentia just before the ejaculatory
duct.

318 The Ohio Journal of Science [Vol. X\"I, No. 7,

Musculature System.

The most noteworthy features of the musculature system
are the powerful muscles of the posterior region of the abdomen.
The pygofer bears the muscles which support and work the
strong ovipositor. The longitudinal muscles of the abdomen
comprise the small ventral muscles of the body wall and the
dorsal muscles. They are segmentally arranged. The lateral
muscles of the abdomen are poorly developed and are confined
to small strands which are situated along the sides of the body.

Nervous System.

The central nervous system (PI. XXII, Fig. 32) consists of
the brain (supraesophageal ganglion), the subesophageal gang-
lion, and the thoracic ganglion, with their attendant nerves
and commissures.

The Brain (Br.) is relatively large and occupies the greater
part of the dorsal region of the head. It emits two pairs of
large nerves, which innervate the eyes (On.) and antennae (An.)
respectively. The brain is connected with the subesophageal
ganglion by the circumesophageal commissures, which are
rather small and not easily recognised. From the subesophageal
ganglion small nerves pass to the maxillae and labium.

The Thoracic Ganglia (T. G.) are fused into one large
ganglion, located on the floor of the mesothorax. Small
commissures connect the thoracic ganglion with the sub-
esophageal, although the two appear to be continuous. Numer-
ous nerves originate from the thoracic ganglion and pass
to the legs, the dorsal muscles and the digestive apparatus.

There are no abdominal ganglia, but two strong nerves
are seen passing back from the thoracic ganglion to the caudal
end of the body. These two main abdominal nerves (Abd. N.)
arise close to one another and are probably the result of the
separation of the abdominal ganglia and commissures. They
become widely separated as they pass down the body on either
side of the median line. Each abdominal segment is supplied
with nerves from these two main commissures and in addition
the reproductive organs, the digestive apparatus and the
excretory system are innervated.

While the Jassid nervous system does not differ very much
from that of a generalized insect, it shows a specialization
in the absence of the abdominal ganglia. However, this is not

May, 1916] Homopterous Studies. Part II 319

an unusual state for the Homoptera, as Kershaw has shown that
in the Fulgorid Pyrops candelaria, the structure and morphology
of the nervous system is essentially the same. The abdominal
ganglia have probably migrated forward and fused with the
thoracic ganglia, leaving the abdominal commissures in their
former position.

Circulatory System.

The Circulatory System so far as observed, consists of a
long tube, or dorsal vessel, which runs the full length of the
body, from the brain to the last abdominal segment. In
general it is an undifferentiated tube, in which the blood
circulates. The pulsation of the dorsal vessel may be observed
by placing a living specimen under the binocular microscope,
and watching the rhythmic movements of the abdomen. The
vessel reaches the brain, which it supplies with blood and then
apparently divides into two branches which pass into the
body cavity.

Conclusions.

The studies enumerated above have led me to the con-
clusion that the Jassoidea can be homologised w4th the other
Homopterous families. The head differs very little from the
fundamental and generalised plan of the Cicada, and while the
Jassid does not show the development of the prominent sulci,
the structure of the mouthparts and head is very similar.
The mandibular setae represent the mandibles and the maxillary
setae, together with the maxillary plate constitute the maxillae.
While for systematic purposes we have been applying general
terms to the regions of the head, it would seem impossible
to change the nomenclature, so as to correspond with the morph-
ological details. The labrum and clypeus are scarcely dis-
tinguishable from one another and the epipharynx is closely
related to the labrum. The tentorium is present and the
invaginations occur as in all insects. There is a well-developed
salivary pumping apparatus. The epicranium is subject to
some modification in size. There is a well developed nervous
system, which is almost entirely cephalo-thoracic. The digestive
system, in the development of a food-reservoir agrees with the
other Auchenorrhynchous Homoptera. In general the plan
and morphology of the internal organs follows that of a gen-
eralised Hemipteron, and the various modifications which occur
in structure are just as likely to be specific as well as generic.

320 The Ohio Journal of Science [Vol. XVI, No. 7,

LITERATURE CONSULTED.

1833. Dufour. Recherches anatomiques et physiologiques sur les Hemipteres.

1860. Flor. Rhynchoten Livlands Vol. 1.

1875. Fieber. Les Cicadines d'Europe. Introduction, pp. 8-31.

1883. Gise. Die Mundtheile der Rhynchoten. Archiv. f. Naturg. Vol. XLIV.

1885. Wedde. Beitrage zur Kenn. des Rhynchotenrussels. Archiv. f. Naturg.

(2) LI.

1886. Miall and Denny. The Structure and Life History of the Cockroach.
1896. Hyatt. Cicada Septendecim, its mouthparts and terminal armour. Am. Mo.

Mic. Journ. Vol. XV. id. Vol. XVII.
1896. Marlatt. The Hemipterous Mouth. Ent. Soc. Wash. Vol. III. pp. 241-2.50.
1896. Melichar. Cicadinen von Mittel-Europa.
1896. Osborn. The Phylogeny of Hemiptera. Ent. Soc. Wash. Vol. III. pp.

lS.5-190.
1896. Melichar. Cicadinen von Mittel-Europa.
1898. Packard. Text Book of Entomology.
1898-1899. Holmgnen. Beitrage zur Kenntnis der Weiblichcn Geschlechtorgane

der Cicadanen. Zool. Jahrb. Abt. fur Syst. XII.
1902. Comstock and Kochi. The Skeleton of the Head of Insects. Am. Nat.

Vol. XXXVI.
1902. Smith. The Structure of the Hemipterous Mouth. Science. Vol. XIX.

No. 478.
1904. Haller. Lehrbuch der Vergleichenden Anatomic.

1908. Bugnion. L'Appareil Salivaire des Hemipteres. Arch. D'Anat. Mic. Vol. X.

pp. 227-268.

1909. Berlese. Gli Insetti. Vol. I.

1910. Gadd. Zur Anatomic der Cicaden und Tettigonia viridis. Revue Russe

d'Entom. X. No. 3. pp. 20.5-213.
1910. Faure-Fremiet. Contribution a L'Etude des Glandes Labiales des Hydro-

corises. Ann. des Sci. Nat. Zool. N. S. 9. Vol. XII.
1910. Kershaw. A Memoir on the Anatomy and Life History of the Homopterous

Insect, Pyrops candelaria. Zool. Jahrb. Abth. f. Anat. XXIX. pp. 105-124.

1910. Pantel and Licent in Bull. Soc. Entom. de France, pp. 36-39.

1911. Bugnion and Popoff. Les Pieces Buccales des Hemipteres (Prem. Partie).

Arch. Zool. Exper. et General. 5e Serie, Vol. VII. pp. 643-674.

1911. Licent. Signification de la dilation proventriculaire chez les Homopteres
superieurs. Bull. Soc. Entom. France, pp. 48-52, 284-296.

1911. Sulc. Uber Respiration, Tracheensystem und Schaumproduktion der
Schaumcikadenlarven. (Aphrophorinae-Homoptera). Zeits. f. Wissensch.
Zool. Band. 99. pp. 147-188.

1911. Muir and Kershaw. On the Homologies and Mechanism of the Mouth-
Parts of Hemiptera. Psyche. Vol. XVIII. No. 1. pp. 1-12. pi. 1-5.

1911. Muir and Kershaw. On the later Embryological Stages of Pristhesancus

papucnsis. Psyche. Vol. XVIII. No. 2. pp. 75-79. PI. 9-10.

1912. Muir and Kershaw. The Development of the Mouthparts in the Homoptera

with observations on the Embryo of Siphanta. Psyche. Vol. XIX. No. 3.
pp. 77-89.

1913. Kershaw. Anatomical Notes on a Membracid. Ann. Soc. Entom. Belgique.

T. 57. pp. 191-201.
1913. Kershaw. The Alimentary Canal of Plata and Other Homoptera. Psyche,
Vol. XX. No. 6. pp. 175-187. PI. 5-6.

1913. Tower. The External Anatomy of the Squash Bug, Anasa tristis DeG.

Ann. Ent. Soc. Amer. Vol. VI. pp. 427-437. PI. LV-LVIII.

1914. Kershaw. The Alimentary Canal of a Cercopid. Psyche, Vol. XXI. No. 2.

pp. 65-72. PI. 4.

1914. Tower. The Mechanism of the Mouthparts of the Squash Bug, Anasa

tristis DeG. Psyche, Vol. XXI. No. 3. pp. 99-108. PI. 1-11.

1915. Peterson. Morphological Studies of the Head and Mouthparts of the

'I'hysanoptera. Ann. Ent. vSoc. Amer. Vol. VIII. No. 1. pp. 22-57. PI. 1-7.

1916. Martin. The Thoracic and Cervical Sclerites of Insects. Ann. Ent. Soc.

Amer. Vol. IX. No. 1.

May, 1916]

Homopterous Studies. Part II

321

ABBREVIATIONS.

A. — Antenna.

Ab. Spi. — Abdominal Spiracle.

Ag. — Accessory gland.

An. — Anus.

An. t. — Anal tube.

A. N. — Antennal Nerve.

a. m. s. — Articulation of the mandibular

seta.
Abd. n. — Abdominal nerve.
Br. — Brain.

BA. — Barrel of salivary pump,
ba. — Barbs of mandibular seta.

C. C. — Circumesophageal commissure.
C. — Central muscles of labium.

c. m. — Circular muscles of labium.
Clyp. — Clypeus.

D. V. — Dorsal valve of ovipositor.
E.— Eye.

E. d. — Ejaculatory duct.
Es. — Esophagus.

E. p. — Entrance to penis,
ep. — Epipharnyx.

G. PI. — Genital plate of male.
G. V. — Genital valve of male.
F.— Follicle.
Fr.— Front.

F. Res. — Food Reservoir.
Hyph. — Hypopharynx.

i. a. — Invagination of the anterior arms
of tentorium.

i. d. — Invagination of dorsal arms of
tentorium.

i. p. — Invagination of the posterior arms
of the tentorium.

i. V. — Inner valve of ovipositor.

L. — Lateral muscles of labium.

lab. — Labium.

labr. — Labrum.

lab. ms. — Labial muscles.

m. a. — Attachment of mandibles to
head-capsule.

mx. a. — Attachment of maxilla to head-
capsule.

md. — Mandible.

mx. — Maxilla.

mi. — Midintestine.

m. p. — Protractor muscles of mandi-
bular seta.

mx. p. — Protractor muscles of maxillary
seta.

m. t. — Mandibular tendon.

mx. t. — Maxillary tendon.

Mx. pi. — Maxillary plate.

M. T. — Main Trunk of tracheal system.

Mp. T. — Malpighian Tubules.

m. r. — Retractor muscles of mandibular

seta,
mx. r. — Retractor muscles of maxillary

seta.
O.— Ocellus.
O. N. — Ocular nerve.
O. T. — Ovarian tubes.
Ov. — Ovary.
Ovd. — Oviduct.
Ovp. — Ovipositor.
O. F. — Occipital foramen.
Pen. — Penis.

P. — Plunger of salivary pump.
Ph. — Pharynx.

Ph. m. — Pharyngeal muscles.
PI. c. — Plates of Clypeus.
Pyg. — Pygofer.
pps. — Protractor muscles of salivary

pump,
prs. — Retractor muscles of salivary

pump.
R. — Rod of plunger.
Rec Sem. — Receptaculum Seminorum.
Rec — Rectum.
S.— Seta.

sg. — Salivary gland,
sd. — Salivary duct.
Subg. — Subesophageal ganglion,
s. p. — Salivary pump,
sd. h. — Salivary duct to Hypopharynx.
Sus. — Suspensor.
T.— Tendon.

T. Spi. — Thoracic spiracle.
Tes. — Testis.
Tg. — Thoracic ganglion,
ta. — Arms of tentorium,
tb. — Body of tentorium,
ts. — Tentorial support.
tr. — Trachea,
v.— Vertex.

VV. — Ventral valve of ovipositor.
Vag. — Vagina.
V. D. — Vas Deferens.

322 The Ohio Journal of Science [Vol. XVI, No. 7,

EXPLANATION OF PLATES.

Plate XX.

Fig. L Ventral view of head of Draeculacephala moUipes.

Fig. 2. Head of Deltocephalus inimicus. Ventral view.

Fig. 3. Head of Agallia sanguinolenta. Ventral view.

Fig. 4. Head of Deltocephalus inimicus. Caudal aspect.

Fig. 5. Head of Draeculacephala moUipes. Caudal aspect.

Fig. 6. Mandible of Deltocephalus inimicus.

Fig. 7. Maxilla of Deltocephalus inimicus.

Fig. 8. Salivary pumping apparatus of Deltocephalus inimicus.

Fig. 9. Cross section through head and eyes of Deltocephalus inimicus.

Fig. 10. Cross section through pharnyx of Deltocephalus inimicus.

Fig. IL Cross section through anterior of clypeus of Deltocephalus inimicus.

Fig. 12. Cross section through labium of Draeculacephala mollipes.

Fig. 13. View of labium of Draeculacephala mollipes.

Fig. 14. Labrum and epipharynx of Draeculacephala mollipes.

Fig. 15. Side view of salivary pumping apparatus of Deltocephalus inimicus.

Fig. 16. Mandibular seta of Deltocephalus inimicus.

Fig. 17. Maxillary seta of Deltocephalus inimicus.

Plate XXL

Fig. 18. Antenna of male Idiocerus.

Fig. 19. Antenna of Deltocephalus inimicus.

Fig. 20. Antenna of Cephalelus infumatus.

Fig. 21. Antenna of Gypona sp.

Fig. 22. Longitudinal median section through Draeculacephala mollipes (semi-
diagrammatic).

Fig. 23. View of food reservoir.

Fig. 24. View of food reservoir.

Fig. 25. Ventral view of genitalia of Phlepsius irroratus. (male.)

Fig. 26. Side view of male genitalia of Phlepsius irroratus.

Fig. 27. Penis of Deltocephalus inimicus.

Fig. 28. Side view of inner valves of ovipositor of Deltocephalus inimicus.

Fig. 29. Ventral view of female genitalia of Draeculacephala mollipes. (Valves
of ovipositor dissected free).

Fig. 30. Side view of ovipositor and female genitalia of Deltocephalus inimicus.

~' " Ventral view of female genitalia of Phlepsius irroratus.

Fig! 3L

Fig. 32.

Plate XXII.

General dissection of Central Nervous System of Draeculacephala
mollipes (semi-diagrammatic).
Fig. 33. General dissection of the tracheal system of Deltocephalus inimicus.

(vSemi-diagrammatic. )
Fig. 34. View of digestive system of Athysanus exitio.sus.
Fig. 35. General dissection of the male reproductive organs.
Pig. 36. General dissection of the female reproductive organs.

Ohio Journal of Science.

Vol. XVI. Plate XX.

JLtic S. Cog an.

Ohio Journal of Science.

Vol. XVI, Pl.^te XXI.

Eric S. Cog an.

Ohio Journal of Science.

Vol. XVI, Plate XXII.

€>

Eric S. Cogan.

A NEW TINGID FROM TENNESSEE.

Carl J. Drake.

The genus Leptostyla, founded by Stal in the Eniimeratio
Hemipterorum, Band. Ill, p. Ill et 125 m 1873, was based on
three new species of Tingitidee from Rio Janeiro, Brazil. Dr.
Stal also referred the Nearctic species, Tingis oblonga to the
genus Leptostyla. In the Biologia Centrali- Americana (Rhynch.,
Vol. II, p. 11, 1897) Dr. G. C. Champion amplifies Stal's generic
description of Leptostyla and describes seventeen new species from
Central America.

The new species of Leptostyla described herein was taken
about fifteen miles west of Clarksville, Tennessee, July 25th,
1915, by Mr. D. M. De Long while sweeping for Jassids. This
pretty little species is quite distinct from the onl}^ Nearctic
congener, L. oblonga Say, and can be easily differentiated from
it by the following key:

First segment of the antennae about three and a half times as long as the second;
costal area of the elytra without a broad fuscous fascia just before the
middle L. oblonga Say

First segment of the antennae twice as long as the second; costal area of the
elytra with a rather broad, dark, fuscous, transverse fascia just before the
middle L. costofasciata n. sp.

Leptostyla costofasciata spec. nov.

Somewhat closely allied to L. const ricta Champion, but
readily separated from it by the longer third segment of the
antennae, the trispinous head, the more heart-shaped anterior
portion of the pronotum, and the much less constricted elytra.
From the only described Nearctic congener, L. oblonga Say,
it is quite distinct and can be readily separated from it by the
characters given in the key, and, also, by the rather blunt
and less prominent spines upon the anterior portion of the head.

Body moderately long and comparatively broad. Head short, with
three rather blunt, porrect and slightly upwardly directed spines — the
two smaller slightly converging spines situated just above the antennae
(one on the inner side of each) ; the larger, frontal spine is just above
the other two; it extends a little farther forward and is slightly curved
downward. Eyes rather prominent, strongly faceted; the facets
giving them a morular appearance. Antenna; slender, about one-half
the length of the body; first segment swollen, twice as long as the

326

May, 1916]

New Tifigid from Tennessee

327

second; second segment incrassated, very short; third segment quite
long, slender, slightly more than three times as long as the fourth;
fourth segment fusiform, pilose. Rostral groove rather wide, uninter-
rupted; rosti-um almost reaching the meso-metasternal suture. Pro-
notum narrowed anteriorly, with the membranous margins moderately
wide, recurved, converging anteriorly, with two rows of areolse; hood
oval, short, considerably raised, with eight areolae on each side; the
three longitudinal carinas raised and when viewed from the side, com-
posed of a single row of areolae (middle carinae more strongly raised
than the other two), intermediate spaces between coarsely and quite

Fig. 1. Leptostyla costofasciata n. sp. (From camera lucida drawing of type by

J. I. Hambleton.)

regularly punctured. Elytra rather long, slightly constricted about the
middle, rounded at the tip, and extending far beyond the apex of the
abdomen; costal area moderately wide, rather coarsely reticulated,
with two rows of areolae; subcostal area rather closely reticulated;
discoidal area not reaching the middle of the elytra, more coarsely
reticulated than the subcostal area; sutural area rather coarsely and
unevenly reticulated, with two large areolae near the tip. Wings not
longer than the abdomen.

Color: First and fourth (except small basal portion) segments of
antennas, nervures of hood testaceous. Third and basal portion of
fourth segment of antenna and legs (tips of tarsi fuscous) yellowish.

328 The Ohio Journal of Science [Vol. XVI, No. 7,

Eyes and central portion of pronotum black. Outer membranous
margins of the pronotum (except nervures of four or five areolae near
humeral angles) , apex of pronotum, areolae of hood and longitudinal carinae
white. Elytra with a rather broad, transverse, dark-fuscous fascia
just before the middle; apex fuscous with whitish areolte; costal area
white, except fascia. Nervures of subcostal, discoidal, and sutural
areas fuscous; the areolae whitish.
Length 2.2 mm.; width 1.1 mm.

Described from three specimens taken at Clarksville,
Tennessee.

Leptostyla oblonga Say.

Journ. Acad. Sci. Phil., Vol. IV, p. 325, 1825; Compl. Writ., Vol. 11, p. 248,
1859 (Tingis).

This species is a little larger than the one described herein.
It was described from specimens taken in Missouri. We
have specimens from Arkansas (Osborn) and Washington,
D. C. (Heidemann). The head has three elongate, acute
spines upon the anterior portion and the costal area of the
elytra is without a fuscous fascia.

Ohio State University.

Date of Publication May 15, 1916.

THE

Ohio Journal of Science

PUBLISHED BY THE

Ohio State; University Scientific Society
Volume XVI JUNE, 1916 No. 8

TABLE OF CONTENTS

Shideler — The Ordovician-Silurian Boundary 329

Reed — The Epibranchial Placodes of Squalus Acanthias 386

HoRSFALL — Additions to the Jassoidea of Missouri 354

Price— Starch in Apple Trees 356

SCH AFFNER — A General System of Floral Diagrams 360

THE ORDOVICIAN-SILURIAN BOUNDARY.

W. H. Shideler.

Of late there has been an increasing disagreement as to just
where the Ordovician-Silurian division should be drawn, and
there has developed a strong movement toward shifting the
division plane from its old and commonly accepted position
at the Richmond-Albion (Upper Medina-Brassfield or "Ohio
Clinton") break, down to the Maysville-Richmond break, thus
incorporating the whole of the Richmond into the Silurian.

The shift in boundary is proposed* primarily for the following
reasons, to express them briefly:

1. Only about 5% of the Maysville species are common to
the Richmond, and these are nearly all generalized and long-
lived types, while the Richmond introduces twenty new generic
and four new family types; while all of the Bryozoa, Echino-
dermata, and most of the corals, trilobites and brachiopods
are strikingly different.

2. The Ordovician relationships of the Richmond are
neutralized by an equally strong Silurian tendency when
compared with the Silurian.

*E. O. Ulrich. The Ordovician-Silurian Boundary. Etude faite a la XII.
Session du Congres geologique international, reproduite du Compte-Rendu.

329

330 The Ohio Journal of Science [Vol. XVI, No. 8,

3. The Richmond- Albion break is regarded as impracticable
for the separation of major time units, because there is no break
there in the Anticosti series, and the break between the Lower
Medina (Queenstown-Juniata — Richmond) and the Upper
Medina (Albion — Brassfield or "Ohio Clinton") is frequently
obscure.

4. The later Maysville seas were notably restricted, and
at the close of the Maysville were drained away. The Arnheim
shale (earliest Richmondf) was deposited over the gently
warped surface of the interior, and the break is shown in
overlap" irregularities in sequence and thickness of deposits.

This break is correlated with larger and more distinct breaks
in the Appalachian and other regions.

These points willbe briefly discussed in order. However,
it may be said here that the writer holds that in so far as crustal
warpings and their consequent changes in land and sea relations
are concerned, they are best reflected in the faunal changes which
take place. The less local and more wide-spread the movement
the greater the effect upon the life of the time. It is held that as
a general proposition slight oscillations have but little repressive
effect upon the forms of a given area, and but few new forms
are introduced, while broad movements are likely to result in
decided repressions on the one hand, and radical innovations on
the other, and actual physical records of diastrophism might well
be lost, obscured or inaccessible, and yet be reflected in a very
positive and far-reaching way upon the life of the times.

1. In comparing the life of the Maysville with that of the
Richmond, faunal lists have been based upon the recently
published Bibliographic Index of American Ordovician and
Silurian Fossils.* This has been modified by data collected
by the writer and by Prof. S. R. Williams during seven seasons'
systematic field work in the disputed strata. The lists include
fossils from the Maysville of the Cincinnati dome, of New York
and of Canada, and Richmond fossils from the Cincinnati
region, the upper Mississippi Valley, and from the Fernvale

t In ascending order the subdivisions of the Richmond are commonly given
as Arnheim, Waynesville, Liberty, Whitewater, Elkhorn, and Belfast. The
Saluda is the western shallow-water equivalent of the upper half of the White-
water and all of the Elkhorn.

* R. S. Bassler, Bull. 92, U. S. Nat. Mus., 1915.

June, 1916] The Ordovician-Silurian Boundary 331

of Illinois, Tennessee, Missouri, Arkansas and Oklahoma.
The reasons for excluding the Anticosti series will be given
later.

In these lists all forms of problematic origin, doubtful range
and uncertain relationships have been excluded.

Of the 413 Maysville species, 58, or about 14%, lived on
into the Richmond. Nor are all species of generalized types
and long range, but we have among them such highly specialized
cystoids as Streptaster vorticellata, Agelacrinus cincinnatiensis
and Cyclocystoides magnus, while Bassler lists the starfish
Hudsonaster incomptus and Mesopalaeaster shafferi. Heter-
ocrinus juvenis and locrinus subcrassus represent the crinoids.
Eleven species of Bryozoa are common, ten of Brachiopoda, six
Pelecypods, ten Gastropods, four Ostracods, etc., etc.

Of the 217 Richmond genera, 116 are common to the Mays-
ville. Of the 101 which are not, 68 occur below the Maysville,
leaving 33 genera which are really new. And these introduce
five new families, the Fenestellidae, Rhopalonariidae, Bato-
criniidae, Halysitidse and Loxonematidae.

2. But contrast with this the fact that the Upper Medina
(Albion) and Clinton give 255 genera, only 82 of which have
been found in the Richmond, and of these 68 are long-ranging
groups, which came up from Pre-Richmond times, usually
Black River or Trenton.

Of the 173 genera not common to the Richmond, 40 also
lived below the Richmond, leaving 133 as really new. And
these 133 new genera introduce 35 new families, the suborders
Larviformia and Sagenocrinoidea, the orders Madreporaria,
Diploporita and Streptophiuriae, and the subclass Hexacoralla.
Should we consider the Upper Medina alone the proportion of
new major groups would be still greater.

Compared with the above record the innovations of the
Richmond seem almost lonesome, and the faunal break looms
up still greater when we consider that of all the Richmond
species, but one lone species, Halysites catenularia, occurs in the
upper strata. But more of Halysites presently.

In comparing two faunas there is a difference of quality
as well as of quantity, and both are of conspicuous value in
comparing the Richmond and the Upper Medina-Clinton
faunas.

332 The Ohio Journal of Science [Vol. XVI, No. 8,

To make a direct comparison between these two groups of
faunas and see just how much the Ordovician relations of the
Richmond are neutralized by the Silurian tendencies, 14% of
the Maysville species are common to the Richmond, and but
one Richmond species goes on up into the Upper Medina or
Clinton.

While 68% of the Maysville genera pass the break into the
Richmond, less than 4% of the Richmond genera pass on into
the Upper Medina or Clinton. Or, if we add 10 Richmond
genera that do not reappear until the Niagara, we still get
less than 5% to compare with the 68% of Maysville genera
passing into the Richmond.

The differences between faunas are shown not only in the
introduction of new types, but also in the disappearance of
old ones. Making new comparisons on that basis, 54 Maysville
genera are absent from the Richmond, though 15 of these
reappear later, leaving 39 which, so far as the strata have
afforded us any knowledge, became extinct at the close of the
Maysville. This would be very nearly 23%, and it includes
three major groups, the families Pattersoniidae, Anomalo-
crinidae and Trinucleidae.

In the case of the Richmond, we find 136 genera are absent
from the Upper Medina-Clinton. But 16 of these reappear
later, leaving 119, or over 54%, of the Richmond genera which
became extinct, as compared with the 23% in the previous
case. And here we have represented the extinction of 14
families, to compare with the 3 closing with the Maysville.

It is because the Anticosti strata are regarded as filling in
the stratigraphic break between the Richmond and the Upper
Medina, while their fossils fill in the faunal break and give
us a faunal transition, that they were not considered in making
up the faunal lists here considered.

Somewhere during Pre-Albion times there must have been
evolving all of the species, genera, families, etc., which appear
so suddenly and are so radically difTerent from the Richmond
forms. These groups, judged by the standards of present day
evolutionists, must have required a very long time for their
differentiation. It is not to be expected, then, that during
all of this time at least a few of the hardier, wide-ranging
forms should have migrated around their barriers into the
Richmond sea? Broad diastrophic oscillations began in the

June, 1916] The Or dovician- Silurian Boundary 333

Maysville and culminated at the close of the Richmond, and
the temporary lowering of barriers would be expected to let
in a few forms. But it is significant that only a few new genera
and only one species are common to the Richmond and the
Upper Medina-Clinton, and the great invasion does not come
in until after the Richmond-Upper Medina break. That
break must have ended in the broader letting down of faunal
barriers.

It may be said that H. catenularia is absent from the
Richmond of the Cincinnati area, but it should occasion no
surprise should it be found here.

3. When two series of strata are separated over broad
areas by both a distinct physical break and a radical faunal
difference, it should detract little if any from the value of that
break as a division plane, should there somewhere be dis-
covered a series of strata filling in the break.

For it is inconceivable that there should be erosion over
the whole earth at once. Somewhere there must have been
bodies of water, and in these must have accumulated the
record of strata and of fossils which is represented elsewhere by
the physical break. So, unless removed by subsequent denuda-
tion, there must exist somewhere a complete physical and
faunal record of each break.

Therefore the filling in of such lost intervals is but to be
expected, and it is not the presence of such transition strata
which determines the value of the break, but it is the amount
of sedimentation and the horizontal distribution of the transition
strata, the amount of erosion and the degree of faunal break
over broad areas, which determine the value.

4. If the Richmond-Upper Medina boundary, so distinct
in'Ohio, Indiana and Kentucky, be impracticable because the
Richmond-Albion boundary is occasionally obscure, and if it
thereby be degraded to a minor position, then the same thing
certainly should apply to the Maysville-Richmond break, which
may show a decided physical break in the Appalachians or
elsewhere, but shows either the most obscure kind of a break
in Ohio, Indiana and Kentucky, or else none at all.

It is to be expected in the shallows about the ocean
margins that every little movement of the shore line will be
strongly marked in the accumulating sediments. Here every
little oscillation will produce a physical break, and the results of

334 The Ohio Journal of Science [Vol. XVI, No. 8,

a fair sized movement would be quite conspicuous. Yet even
a fair-sized movement probably would show little or no effect
upon the main sedimentation or upon the life of the sea as a
whole.

Such appears to be the case with the Maysville-Richmond
break. We should naturally expect to find breaks about the
shores of the interior sea of this time, and we do get them in
New York, Pennsylvania, Tennessee, etc., but over the broad
interior, there is but scanty and obscure evidence of such a
break.

It is not intended to deny the presence of such a break, but
this break is held to have been the result of a broad though
feebly developed and fleeting upwarping, not to be compared
either physically or faunally in its results with later movements.

If the Arnheim be taken as the basal member of the Rich-
mond, then it cannot be said that there is any definite physical
break between the Maysville and the Richmond, at least in
Ohio, Indiana and Kentucky.

The evidence as shown in overlap irregularities in sequence
and thickness of deposits is inconsistent and obscure at the
best. And the evidence is much less distinct than it is in the
case of the breaks at the top of the Arnheim, at the base of the
Whitewater (Gyroceras baeri zone, where in Adams County
and elsewhere there is a veritable basal conglomerate), at the
base of the Saluda, within the Saluda and at the top of the
Saluda-Elkhorn.

To summarize the evidence here presented, the Maysville-
Richmond break is found to be inconvenient and inadequate
physically. Regardless of the evidence of physical breaks, the
close relationships of the two faunas speak for itself.

And the radical difference between the faunas of the Rich-
mond and the Upper Medina-Clinton indicates a greater period
of disturbance and a greater letting down of barriers than
in the case of the close of the Maysville.

To make a few more comparisons, 58 times as many Mays-
ville as Richmond species pass on up; 4 times as many new
genera and 7 times as many new families are introduced during
the Upper Medina-Clinton as are introduced during the Rich-
mond ; nearly 5 times as many families close with the Richmond
as close with Maysville; 3 times as many genera failed to pass

June, 1916] The Ordovician- Silurian Boundary 335

the Richmond-Upper Medina break as failed to pass the
Maysville-Richmond break.

Retaining, then, the Ordovician-Silurian boundary at its
old and generally accepted position between the Richmond and
the Upper Medina, a slight refinement may be made in the
drawing of the boundary in Ohio.

The Richmond has been considered as ending with the
Belfast* beds, a series of strata developed in Ohio along the
east side of the Cincinnati dome. They are generally barren of
fossils, and chiefly on the basis of rather common annelid
remains have been classed as Ordovician, despite the finding
of Halysites catenularia and Orthis flabellites in them. But
during the past season there have been added to these Dal-
manella elegantula and var. parva, Rhynochonella janea and
Hormotoma sublata, all found near Lawshe and near West
Union, Adams County, Ohio.

Disregarding the annelid remains, which cannot be used in
correlating anything, the total fauna of the Belfast is Brassfield
(Upper Medina) in its affinities.

The Ordovician-Silurian boundary of Ohio, Indiana, and
Kentucky should be drawn, then, at the top of the next under-
lying beds, the Elkhorn and its equivalents.

* Foerste, Jour. Cin. Soc. Nat. Hist., Vol. XVIII, Feb., 1896, pp. 161-199.

Miami University.

THE EPIBRANCHIAL PLACODES OF SQUALUS

ACANTHIAS.

(Fifty-two Figures and Two Tables.)

Carlos I. Reed,
From the Department of Anatomy of The Ohio State University.

The study of the epibranchial placodes of Squalus Acanthias
was undertaken with a view to determining whether this type
displays the characteristics with regard to contribution of cells
to the visceral ganglia of the gill region by the corresponding
placodes, which were described by Landacre ('10) in the catfish
and ('12) Lepidosteus osseus.

In the catfish, this author described a contribution en
masse, of placodal cells to Gang. VII, IX and X, by the cor-
responding placodes and concluded that the cells from these
sources gave rise to gustatory or special visceral fibers.

In Lepidosteus, it was shown that the method of contribution
begins by active proliferation of cells of the ectoderm, thus
forming the placode. This process is followed by a contact
between the ganglia and the placodes, due to a mesial migration
resulting in the fusion of the placodal cells with the general
visceral components of VII, IX and X. In Rana, Landacre
and McLellan ('12) were unable to distinguish a definite gus-
tatory division in the ganglia of the 8 mm. larva probably on
account of the more rapid development in this form; but these
authors describe the behavior of the epibranchial placodes as
similar to that observed in Lepidosteus and Ameiurus, and also
describe well defined placodes in the stages earlier than the
8 mm. larva.

The material used consisted of a 20 mm. shark embryo cut
into sections 10 microns thick, stained with Delafield's hema-
toxylin and counter-stained with Orange G. An 18 mm.
embryo, subjected to the same technic was used for comparison.
All drawings were made with a camera lucida in magnifications
of 50x and 620x respectively, and reduced to one-third the
original size in reproduction.

Owing to the difficulty of securing successive stages of
Squalus at close intervals, this study is based upon a comparison
of all the epibranchial placodes in one specimen. The placodes

336

June, 1916] Epibranchial Placodes of Squal us Acanthias 337

appear in other forms, as do the branchial clefts, in serial order
from anterior to posterior, and it seemed probable that the
various stages in development of the placodes of the VII, IX
and of the four divisions of the X nerve would present the same
kind of evidence that could be secured by a study of one placode,
such, for instance, as that of the IX nerve, through a series of
embryos of successively older stages.

In determining the relation of a visceral ganglion to the
ectoderm, it is necessary to distinguish carefully, the following
ectodermal thickenings: fa) the lateral line placode; (b) the
thickening of the ectoderm at the point where the entodermal,
pharyngeal pocket joins the ectoderm; (c) the ectodermal
thickening extending anterior and posterior to (b) ; (d) thick-
enings of the epithelium of the entodermal, pharyngeal pocket
which, after the gill slits are open, are continuous with the
corresponding ectodermal thickenings (b).

A comparison of the 20 mm. and 18 mm. stages indicates
that, of the ganglia in question, the VII undergoes the earliest
development, hence, in the later stages, presents a more highly
developed condition, and here, the placode is very m.arked and
easily distinguishable from the thickenings associated with the
gill clefts.

The placodes are characterized by a thickening of the
ectoderm, by irregular arrangement of the cells, and by the
presence of numerous mitotic figures, indicating rapid cell
proliferation.

In the cases where actual cell contribution is observed, this
activity takes place almost uniformly by migration of the cells
from the placode toward the ganglion, followed by metamor-
phosis as follows ; the cells on the mesial border of the migrating
mass exhibit the characteristic darkly-staining, granular nuclei
described by Landacre in Lepidosteus; in some cases, also,
smaller size of the nuclei than those of the placodal cells that
have not migrated, or of the cells of the visceral components,
though this is by no means as constant as in Lepidosteus, and
in fact, was not clearly marked in any case except Gang. IX.

Table I shows the ratio between the length of the area of
contact between the placodes and the ganglia, and the total
length of the ganglia themselves. It will be seen from this
that the lengths of the areas of contact increase as we pass

338 The Ohio Journal of Science [Vol. XVI, No. 8,

posteriorly while the lengths of the ganglia diminish. Thus,
there is, progressively, a greater extent of contact between the
placodes and ganglia in proportion to the length of the ganglia.
This is evidence of the greater maturity of the more anterior
ganglia, which is in accord with the general law of antero-
posterior differentiation.

TABLE I.
(Showing length of ganglia and contact area in 20 mm. embryo.)

Gang. Length of Ganglia Length of Contact Area Ratio

VII 340 microns 10 microns 1-34.

IX 190 " 40 " 1-4.75

Xi 270 " 90 " 1-3.

X2 130 " 90 " 1-1.46

X3 150 " 120 " 1-1.25

X4 210 " 160 " 1-1.4

Table II shows the length of the area of contact in the 18
mm. stage. The development has not progressed to the degree
seen in the older stage and, consequently, there is less difference
in the lengths of the contact areas in the younger stage than
in the 20 mm. stage. The placodal contributions are propor-
tionately much larger when compared to the size of the general
visceral portions than in the older series. This is evidence that
the total absence of the darkly-staining cells in the 22 mm.
embryo, examined in connection with other work in progress in
the department, may be interpreted as meaning, only, that
these cells, in the latter case, have undergone complete meta-
morphosis and mersion with the general visceral cells so that
they do not stain differently. This is also the probable expla-
nation of the failure to distinguish them in Rana (Landacre
and McLellan '12), since this form undergoes relatively more
rapid development and the process was completed in the earliest
stages studied.

TABLE II.

(Showing length of contact area in 18 mm. embryo.)

Gang. Length of Contact Area

VII ISO microns

IX 160

Xi 100

X2 90

X, SO "

X4 100

June, 1916] Epibranchial Placodes of Squalus Acanthias 339

Gang. VII.

Since this ganglion is the earliest to develop, there is, in
the 20 mm. stage, a relatively small number of cells showing the
characteristic distinguishing features of placodal cells. The
ganglion is 340 microns long, but for only 10 microns or through
one section, was there any actual contact with the ectoderm,
while in the 18 mm. stage there is contact through 18 sections
or 180 microns (Tables I and 11). In the 22 mm. stage, there
is no contact and no cells which show the characteristic nuclei
to a degree sufficient to permit of their being distinguished from
the general visceral cells.

In the 20 mm. embryo, most of the ganglion lies anterior and
dorso-mesial to the anterior extremity of the first true gill cleft,
and the point of contact is just opposite the anterior end of the
cleft. There are a number of mitotic figures in the placode and
the migrating cell mass, showing that the processes of prolifera-
tion and metamorphosis are not yet com.pleted.

The placode is an extensive thickening of the skin and at
one point (Fig. 1 and 8), there seems to be a tendency to-
lamellation. The placode lies quite free and distinct from the
thickening of the ectoderm which accompanies the opening-
of the gill cleft (c). Throughout most of its extent, the ganglion
shows a well defined, encapsulated outline, which condition
indicates maturity since it is not present to so great a degree in
the more posterior ganglia.

The ventro-lateral lateralis component (Fig. 1 to 9, V. L.
VII), constitutes the dorsal portion of the ganglionic mass and
extends several sections posterior to the limits of the visceral
portion.

Gang. IX.

This ganglion is 190 microns in length and the contact area
occupies 40 microns of this length, giving a ratio of 1-4.75
between the total length and the length of the area of contact.
The point of contact is approximately opposite the middle of
the gill cleft and toward the posterior end of the ganglion. In
the 18 mm. stage, the contact area is 160 microns long and so
is not much smaller in extent than the contact area of VII in.
the same stage (Table II).

340 The Ohio Journal of Science [Vol. XVI, No. 8,

The placodal thickening of the ectoderm is not so marked as
in VII, but the irregular arrangement of the cells, the presence
of mitotic figures and the tendency to lamellation of the placodal
mass (Fig. 14 and 15) are evidences of the integrity of the mass,
which is cjuite distinct from the lateralis placode and, toward
the posterior end of the ganglion, from the gill cleft thickenings
also. The outline of the general visceral portion of the ganglion
is maintained for several sections posterior to the point of con-
tact (Fig. 10) with the placodal mass, and the boundary line
between this and the placodal m.ass is quite distinct and intact
at some points (Fig. 10, 11, 12 and 15).

In the mass of contributed cells, as well as in the placode,
there are numerous mitotic figures and there is, in every sec-
tion, a large group of undifferentiated cells (Fig. 11 to 15), lying
near the ectoderm, except near the anterior extremity of the
ganglion. Mesial to this mass is an area of cells with much
smaller, dark, granular nuclei, representing a stage of incom-
plete metamorphosis (Fig. 10 to 16, S. V. VII). The boundary
between this and the general visceral mass is quite abrupt and
distinct in most sections, but in some there is evidence of fusion
with the latter mass (Fig. 13). These facts are presented as
-evidences of the active state of proliferation and metamorphosis.

The process of contribution to the ganglion does not persist
posterior to the point of disappearance of the general visceral
portion, though the placode persists several sections posterior
to both.

It will be seen from these conditions, that Gang. IX presents
a much less mature condition than Gang. VII, which is to be
expected from the evidences already presented (Tables I and II).

Gang. X.

The main mass of the ganglion does not come into contact
with the ectoderm except at the extreme posterior extremity;
instead, it gives off four branchial ganglionic masses which
extend ventro-lateral something after the manner of the fingers
of a hand, and come into contact with the ectoderm of the
third, fourth, fifth and sixth gill bars respectively. The length
of each branchial division is measured from the point of its
complete separation from the main ganglionic mass.

June, 1916] Epibranchial Placodes of Squalus A canthias 341

The length of the first branchial ganglion of X, is 270
microns and the area of contact is 90 microns in length and
situated toward the posterior end of the ganglion. This gives a
ratio of 1-3 between the length of the contact area and the
total ganglion length (Table I). In the 18 mm. stage, the
length of the area of contact is 100 microns (Table II).

The oval outline of the ganglion, as seen anterior to the
point of contact, persists posterior to the first section in which
contact is seen (Fig. 22), but finally becomes indented by con-
tact with the placodal mass so that the lateral curve is lost
(Fig. 23 and 24), but the boundary between the general visceral
and placodal components is quite distinct and persists through-
out the entire length of the contact. The contact occurs toward
the posterior end of the gill cleft and is directly mesial to the
external aperture of the cleft. On account of its proximity to
this structure, it is impossible to distinguish the placode from
the other ectodermal thickenings associated with the gill clefts.

In Fig. 22, the cells with dark, granular nuclei lie in contact
with the placode and there are no mitotic figures, showing that
the processes of contribution and metamorphosis are slower in
this region and so, more nearly complete toward the anterior
end of the contact. This is true of all ganglia. In the more
posterior sections (Fig. 23 and 24), there is evidence of more
active proliferation, since there are large masses of undifferen-
tiated cells to be seen, which have probably become detached
en masse, lying near the ectoderm. The smaller size of the
nuclei of the placodal cells is not so marked as in Gang. IX.

The second branchial ganglion of X presents a different
arrangement from the first, in that the point of contact is with
the entodermal evagination from the pharynx which enters into
the formation of the gill cleft, at the anterior end; toward the
posterior end, the contact is with the ectoderm at a point
dorso-mesial to the external aperture of the cleft. The branchial
ganglion is entirely free from the main ganglionic mass of X
several sections anterior to the anterior end of the gill cleft.

The length of the ganglion is 130 microns and the length of
the contact area is 90 microns, giving a ratio of 1-1.46 between
the contact length and the total ganglion length. In the 18 mm.
larva, the length of the contact area is 90 microns, also, though
the length of the ganglion is not so great as in the older stage
(Tables I and II).

342 The Ohio Journal of Science [Vol. XVI, No. 8,,

The distinction between the placode and the gill cleft
thickenings is difficult to determine, at least, in the more
anterior sections, though the irregular arrangement of the cells
of the ectoderm and the presence of a few mitotic figures are
evidences of proliferation. In the first section in which contact
is seen, the mass of contributed cells is quite large and persists
posterior to the point of disappearance of the visceral portion,
so that the placodal portion lies well toward the posterior end
of the ganglion, most of which lies anterior to the middle of
the gill cleft.

The oval outline of the visceral component persists after
contact (Fig. 30) and the boundary between this and the pla-
codal component is quite distinct, even posterior to the point
at which the lateral curve of the visceral mass becomes indented
by contact with the placodal mass (Fig. 31). In the more
posterior sections (Fig. 32 and 33), there is fusion between the
two components to such an extent that the boundary is not so
distinct. There is evidence of rapid contribution in the pres-
ence of a large mass of undifferentiated cells near the ectoderm
(Figs. 30, 31 and 32). The metamorphosing cells possess nuclei
but slightly smaller in size than those of the other cells of the
ganglion.

In the third branchial ganglion of X, also, the most anterior
contact is with the entodermal gill pocket from the pharynx
instead of with the ectoderm (Fig. 34, 35, 36 and 37). The
length of the ganglion is 150 microns and that of the contact
area, 120 microns, giving a ratio of 1-1.25 between the length
of the area of contact and that of the total ganglion. In the
18 mm. larva, the length of the contact area is 80 microns,
showing that the process of contribution has probably not
progressed to so great a degree in the 20 mm. stage as it has in
the VII and IX ganglia in the younger stage (Tables I and II).

In the more anterior regions, it is impossible to distinguish
between the placode and the gill cleft thickenings but, in the
more posterior regions, the distinction is quite clear (Fig. 39,
40 and 41). Proliferation and metamorphosis are evidently
going on quite rapidly throughout the entire length of the
contact and the placodal mass persists in considerable size to
the posterior end of the ganglion. There is no appreciable
difference in size between the nuclei of the metamorphosing
cells and those of the neighboring cells but the dark stain and

June, 1916] Epibranchial Placodes of Squalus Acanthias 343

the granular appearance are in evidence throughout. There is
evidence of active proHferation in the placode, though meta-
;morphosis is evidently not proceeding so rapidly, since the
mass of metamorphosing cells is quite large in proportion to the
size of the mass of undifferentiated cells. There is no distinct
boundary line between the placodal and general visceral com-
ponents, showing that fusion between the two is quite complete.
The placodal mass does not persist to the posterior extremity
of the ganglion but seems to occupy a position about the middle
of this structure.

In the fourth epibranchial of division X, the form and
position of the ganglionic mass are such as to make the con-
tributed mass probably appear larger than it actually is. The
length of the ganglion is 210 microns and that of the contact
area is 180 microns, giving a ratio of 1-1.4 between the contact
area and the total length (Table I). In the 18 mm. embryo,
the length of the contact area is 100 microns. This is further
evidence of a lesser degree of maturity in the more posterior
ganglia.

The point of contact lies dorso-mesial to the middle of the
external aperture of the gill cleft (Fig. 42 to 50). The placode
is easily distinguishable from the other ectodermal thickenings
throughout the entire length of the ganglion (Fig. 43, 44, 45,
47 and 48). The general visceral portion of the ganglion does
not maintain its outline after contact with the mass of contrib-
uted cells and there is such complete fusion between the two
masses that a definite boundary is not discernable except in
Fig. 49. The presence of mitotic figures, the complete fusion
between the general visceral and placodal masses and the
large size of the latter, indicate very rapid proliferation, while
the large size of the mass of incompletely metamorphosed cells
as compared to the size of the mass of undifferentiated cells,
indicates comparatively slow metamorphosis.

In Fig. 45 and 46 there may be seen a constriction in the
mass of contributed cells which later results in complete sep-
aration between the ganglion and the placode (Fig. 47, 48, 49
and 50), leaving a large mass of cells attached to the placode.
This mass, in some sections, shows a tendency to lamellation
(Fig. 49 and 50). Posterior to the point of complete separation
of the ganglion from the placode, the contributed mass is rel-
atively much smaller than the general visceral portion.

344 The Ohio Journal of Science [Vol. XVI, No. 8,

There is another point of contact between the ectoderm and
the main ganghon of X in the post-branchial groove where
there is an appreciable thickening of the skin and a definite
enlargement of the ganglion, also some evidence of contribution
of ectodermal cells to the ganglion, but no separate epibranchial
division.

Summary.

1. The epibranchial placodes of Squalus Acanthias arise as
proliferations of the ectoderm about the middle and dorsal
region of the corresponding branchial clefts.

2. Contribution of cells by the placodes to the visceral
ganglia is by proliferation and mesial migration, the cells
coming into contact with the caudal extremity of the cor-
responding ganglia.

3. With but two exceptions, the placodes are easily dis-
tinguishable from the other ectodermal thickenings in the
same regions.

4. The placodal cells, in the course of migration, undergo a
process of metamorphosis, during which the nuclei become
darker and more finely granular, and in Gang. IX, smaller in
size. In the older ganglia these migrating masses of placodal
cells are completely fused with the general visceral masses and
the cells of the two components are indistinguishable from
each other.

5. There is a general similarity in behavior between the
placodal cells in the shark and those of other forms in which
this process has already been described.

6. The order of maturity of the epibranchial ganglia is
from anterior to posterior, in progressive stages.

LITERATURE CITED.

Landacre, F. L. 1910. The origin of the Cranial Ganglia in Ameivirus. Jour, of

Comp. Neurology, Vol. XX. No. 4, p. 309.
Landacre, F. L. 1912. The Epibranchial Plocodcs of Lcpidosteus osseus and

their Relation to the Cerebral Ganglia, ibid. Vol. XXII, No. 1, p. 1.
Landacre, F. L., and McLellan, Marie. 1912. The Cerebral Ganglia of The Embryo

of Rana pipiens, ibid. Vol. XXII, No. 5, p. 461.

June, 1916] Epibranchial Placodes of Squalus Aca?ithias 345

EXPLANATION OF FIGURES.

All drawings were made from the posterior surfaces of 10 micron sections,
with a camera lucida. Outline drawings were magnified oOx; high power draw-
ings were magnified 620x. All figures were reduced to one-third the original size
in reproducing. The sections are numbered serially from anterior to posterior,
showing the relations of the sections used in the drawings.

KEY TO ABBREVIATIONS.

Aud. — Auditory vescicle.

Ec. — Ectoderm.

G. C— Gill cleft.

G. V. VII — General visceral portion of the seventh ganglion.

G. V. IX — General visceral division of the ninth ganglion.

G. V. Xi, Xa, X3, X4 — General visceral divisions of the first, second, third and

fourth epibranchial ganglia of the tenth nerve.
G. X — The main ganglionic mass of the X nerve.
L. IX — Lateral line portion of Gang. IX.
L. X — Lateral line portion of Gang. X.
L. PI. — Lateral line placode.
M. — Metencephalon.
PL— Placode.

S. V. VII — Special visceral portion of Gang. VII.
S. V. IX — Special visceral portion of Gang. IX.

S. V. X — Special visceral portion of the main ganglionic mass of the X nerve.
S. V. Xi, X2. X3, X4 — Special visceral divisions of the first, second, third and

fourth epibranchial ganglia of the X nerve.
V. — Blood vessel.
V. L. VII — Ventral lateral line division of Gang. VII.

Plate XXIII.

Fig. 1. Sec. No. 216. Gang. VII, showing the placodal (PI) thickening of the
ectoderm at a point opposite the ganglion. The placodal contribution is small at
this point and is characterized by the presence of cells with darkly staining nuclei;
there are a number of mitotic figures, indicating active proliferation. Actual
contact between the ganglion and the ectoderm is not present in this section.

Fig. 2. Sec. No. 222. G. VII. The distinguishable portion of the placodal
contribution is much larger than in the preceding figure. There is a contact
between the ganglion and the ectoderm, and the fact that the most external cells
of the contributed mass do not show the characteristic dark nuclei, indicates
active contribution of cells by the placode. The most recently contributed cells
have not yet undergone the stage of metamorphosis seen in those that have
migrated farther into the body of the ganglion.

Fig. 3. Sec. No. 224. G. VII. In this section, there is a reduction in the
comparative size of the placodal component, absence of contact and a reduction in
the number of mitotic figures, from the number in previous sections.

Fig. 4. Sec. No. 227. G. VII. There is still further reduction in the compar-
ative size of the placodal component and a comparatively large area of undifferen-
tiated cells on the external portion of the ganglion near the ectoderm.

Fig. 5. Sec. No. 231. G. VII. There is no evidence of actual cellular contact
between the placode and the ganglion and, while still very near the placode, there
is no evidence of recently contributed, undifferentiated cells on the lateral
periphery of the ganglion.

Fig. 6. Sec. No. 233. G. VII. The dorsal portion of this section and the
sections already described, constitute the lateral line component of VII (V. L.
VII), the lower portion, the general visceral component; the latter, in this section,
occupies an area of about the same extent as the placodal component, though this
is reduced from the extent displayed in the previous section. There is still some
active proliferation as evidenced by the presence of mitotic figures, not all of
which are in focus at this level.

Fig. 7. Sec. No. 237. G. VII. The body of the entire ganglion is not so clearly
defined at this point as in the more anterior and more mature portions. The
placodal thickening is not greatly reduced and there is evidence of very active cell
proliferation, though actual continuity of cellular elements is doubtful.

Fig. 8. Sec. No. 216. G. VII. An outline drawing of the same section as Fig. 1,
showing the general relations of the area. The lateralis component is relatively
smaller than the general visceral. The relation of the entire ganglion and the
placode to the first gill cleft is clearly seen. There can be no doubt as to the
independence of the placodal thickening from that situated at the opening of the
gill cleft.

Fig. 9. Sec. No. 224. G. VII. An outline drawing of the same section as Fig. 3.
The branchial cleft has deepened and the gill cleft thickening of the ectoderm is
consequently carried farther away from the placodal thickening, which still
maintains the form and size displayed in the intervening sections, as well as in
those situated more posteriorly.

Ohio Journal of Science.

Vol. XVI, Plate XXIII.

■Carlos I. Reed.

Plate XXIV.

Fig. 10. Sec. No. 278. G. IX. A high power drawing of the most anterior
section of Gang. IX in which there is contact with the ectoderm. The placodal
thickening is quite marked and there is some evidence of active proliferation in
the placodal area. The cells of the placodal component are smaller than those of
the general visceral portion. There are a few cells near the ectoderm which have
evidently been recently contributed from the placode and have not yet undergone
metamorphosis.

Fig. 11. Sec. No. 280. G. IX. In this section, the smaller size of the nuclei of
placodal cells is quite marked. The outline of the general visceral component is
easily distinguishable throughout part of the extent of the contact with the pla-
codal portion. Here again, may be seen a small mass of undifferentiated placodal
cells lying near the ectoderm.

Fig. 12. Sec. No. 281. G. IX. In this section, the metamorphosing cells are
completely surrounded by undifferentiated cells. The presence of mitotic figures
indicates active proliferation.

Fig. 13. Sec. No. 282. G. IX. The extent of the contact with the ectoderm is
greater than in the previous section. Proliferation must be going on more rapidly
than metamorphosis, since the mass of undifferentiated cells near the ectoderm
is larger and shows the cells massed more closely and tending to form lamellae.

Fig. 14. Sec. No. 284. G. IX. In this section, proliferation is very rapid as
evidenced by the large mass of imdifferentiated cells and the comparatively
narrow field of placodal cells which have undergone metamorphosis. The marginal
extent of contact is shorter than in the more anterior sections.

Fig. 15. Sec. No. 286. G. IX. The contributed portion of the ganglion is very
large in proportion to the size of the general visceral ganglion. Several mitotic
figures may be seen and there is a well marked margin of undifferentiated cells.
The placodal thickening is dorso-lateral to the contact area which is still shorter
in extent than in Fig. 14.

Fig. 16. Sec. No. 289. G. IX. The extensive placodal thickening still persists
and active proliferation is still going on.

Fig. 17. Sec. No. 275. G. IX. This section .shows the relation of the lateralis
and visceral components anterior to the point of contact. It is, here, impossible
to distinguish the placodal thickening from that accompanying the gill cleft
opening, which lies ventral to it.

Fig. 18. Sec. No. 278. G. IX. An outline drawing of the same section as Fig.

10. The lateral line placode is very distinct from the epibranchial placode. The
epibranchial placode, since the gill cleft is open, is easily distinguishable from the
gill cleft thickenings of the ectoderm.

Fig. 19. Sec. No. 280. G. IX. An outline drawing of the same section as Fig.

11, showing the relation of the contributed mass to other structures.

Fig. 20. Sec. No. 287. G. IX. An outline drawing one section posterior to Fig.
15, showing the dorso-lateral point of contact.

Fig. 21. Sec. No. 296. G. IX. Showing the appearance of the lateralis com-
ponent of Gang. X, the great thickness of the lateral line placode, and the relative
size of the placodal and general visceral portions of Gang. IX.

Ohio Journal of Science.

Vol. XVI, Plate XXIV.

G V IX.

Carlos I. Reed.

Plate XXV.

Fig. 22. Sec. No. 320. G. Xi. Showing the contact point just mesial to the
•external opening of the gill cleft. There are no mitotic figures in the contributing
area, but there may be seen a very definite zone of metamorphosing cells along
the lateral border of the ganglion.

Fig. 23. Sec. No. 324. G. Xi. Two points of contact are seen and proliferation
is going on quite rapidly, from the fact that there is a large mass of larger and
more clearly stained cells between the two points of contact and external to the
metamorphosing zone. The outline of the visceral portion of the ganglion is only
fairly distinct.

Fig. 24. Sec. No. 326. G. Xi. The mass of metamorphosing cells is almost
surrounded by undifferentiated cells. This, together with the presence of mitotic
figures, indicates active proliferation froin the placodal area.

Fig. 25. Sec. No. 323. G. Xi. An outline drawing of the section anterior to
Fig. 23, showing the general topography and the relation of the ganglion to the gill
cleft and the placode, the latter being indistinguishable from the ectodermal
thickening accompanying the opening of the gill cleft.

Fig. 26. Sec. No. 345. G. X. This section shows the relation of the main
ganglion to the ectoderm and the gill groove. The second epibranchial ganglion
of X, G, V, X2, is seen partly constricted off from the main ganglionic mass. A
lateral line nerve is seen leading to the easily distinguished lateral line organ.

Fig. 27. Sec. No. 350. In this figure, the epibranchial ganglion is seen lying
close to a thickening in the epithelial lining of the pharyngeal gill pouch. This
thickening is continuous, in later sections, with the placodal thickening of the
ectoderm, posterior to the point at which the gill cleft is entirely open.

Fig. 28. Sec. No. 351. The endothelial thickening persists and is nearer the
external aperture of the gill cleft.

Fig. 29. Sec. No. 352. The endothelial thickening is more clearly defined
than in the previous section.

Fig. 30. Sec. No. 352. G. X2. A high power drawing of the same section as in
the preceding figure, showing proliferation and a mass of cells with darkly stained
nuclei which are not appreciably smaller than those of the cells of the general
visceral ganglion. The oval outline of the general visceral portion and the
boundary between this and the placodal portion are clearly seen.

Fig. 31. Sec. No. 353. G. X2. Here the placodal thickening is clearly seen
and there is much evidence of active proliferation.

Fig. 32. Sec. No. 357. G. X.. The placodal thickening is still seen but the
extent of contact with the ganglion is slight. The placodal cells constitute a much
larger mass than the general visceral cells.

Fig. 33. Sec. No. 357. G. X2. An outline drawing of the same section as shown
in Fig. 32.

Fig. 34. Sec. No. 375. G. X3. An outline drawing of a section anterior to the
point of separation of the epibranchial ganglion from the main ganglionic mass of
X; also anterior to the anterior extremity of the gill cleft, showing the lateralis
component and a branch to the lateral line placode.

Fig. 35. Sec. No. 378. G. X3. The outline of the general visceral component is
fairly distinct and the mass of placodal cells relatively large; there is no contact
withjthe ectoderm and it is impossible to distinguish the placode from the gill
cleftithickenings.

Fig. 36. Sec. No. 380. G. X3. The mass of contributed cells is very large but
the placode is still indistinguishable from the gill cleft thickenings.

Fig. 37. Sec. No. 381. G. X3. The general visceral portion of the ganglion is
relatively small; there is evidence of active proliferation and a small area of
contact but the extent of the placodal thickening is small.

Fig. 38. Sec. No. 383. G. X3. The placodal thickening is ciuite marked and
there is much evidence of active proliferation. The outline of the general visceral
portion of the ganglion is quite distinct.

Ohio Journal of Science.

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Plate XXVI.

Fig. 39. Sec. No. 384. G. X3. The mass of contributed cells is much larger
in proportion to the size of the general visceral component, than in the preceding
figure.

Fig. 40. Sec. No. 386. G. X3. The placode is quite marked and there is active
proliferation and an extensive contact area.

Fig. 41. No. 390. G. X3. This section shows the placodal thickening persisting,
even to the posterior extremity of the ganglion, where there is only a slight area
of contact.

Fig. 42. Sec. No. 410. G. X4. The apparently large size of the mass of contrib-
uted cells is probably exaggerated as a result of the peculiar form of the ganglion
at this point. There is evidence of active proliferation but only a short area of
contact.

Fig. 43. Sec. No. 410. G. X4. An outline drawing of the same section as shown
in Fig. 42, showing the relation of the placode to other structures. This mag-
nification does not reveal the contact.

Fig. 44. Sec. No. 412. G. X4. Showing the extensive contact and the large
size of the mass of contributed cells.

Fig. 45. Sec. No. 413. G. X4. The placode is quite distinct from the other
ectodermal thickenings.

Fig. 46. Sec. No. 413. G. X4. A high power drawing of the same section as
shown in the preceding figure, showing evidence of active proliferation. The
outline of the general visceral ganglion is fairly distinct.

Fig. 47. Sec. No. 415. G. X4. Contact between the placode and the ganglion
no longer exists but the placode is very large.

Fig. 48. Sec. No. 418. G. X4. Showing partial detachment by lamellation, of
the placodal mass from the ectoderm.

Fig. 49. Sec. No. 415. G. X4. A high power drawing of the same section as
shown in Fig. 47, showing a large mass of cells contributed by the placode but not
yet metamorphosed. The outline of the general visceral component is fairly
distinct and the nuclei of the placodal cells are slightly smaller than those of the
general cells.

Fig. 50. Sec. No. 420. G. X4. The placodal component is relatively small and
a portion of the placodal mass is partially detached from the ectoderm by
lamination.

Fig. 51. Sec. No. 329. G. Xi. A section of the first division of Gang. X, three
sections posterior to that shown in Fig. 24.

Fig. 52. Sec. No. 428. G. X. Showing the general topography and the
posterior extension of the main ganglionic mass of Gang. X, as it comes into con-
tact with the ectoderm in the post-branchial groove.

Ohio Journal of Science.

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ADDITIONS TO THE JASSOIDEA OF MISSOURI.

J. L. HORSFALL.

In Vol. XVI, No. 2, of this Journal, Gibson and Cogan
published a Preliminary List of the Jassoidea of Missouri in
which 98 species and varieties were recorded. The writer,
while employed by the Missouri Fruit Experiment Station at
Mountain Grove, Missouri, during the past two summers made
a collection of 84 species of Jassoidea in that immediate region.
Unless otherwise mentioned the specimens were collected by
him. In this material are 29 species not listed in the above
named paper. Thanks are due Professor Herbert Osborn of
Ohio State University for verification and determination of six
of the more doubtful species. The notes on the undetermined
forms were furnished by him.

Idiocerus aiternatus Fitch. One specimen taken July 3,

sweeping low shrubs along a pasture creek.
Penthimia americana Fitch. Rare. One specimen dated

July 5, in collection. Probably swept from Black Jack

brush.
Xerophloea viridis Fabricius. Both the plain green and the

dark form taken in September.
Gypona scarlatina Fitch. One specimen in traplight material

from substation at Cuba, Missouri, May 26, 1914.
Platymetopius magdalensis Provancher. From Black Jack

brush in July.
Deltocephalus areolatus Ball. In short grass in peach orchard,

September. Taken sweeping in Winter Emmer by M. P.

Somes, November 8, 1915.
Deltocephalus sp. "Near stylatus Ball but with different

genitalia." Osborn. Common in weedy pastures July,

August, September.
Athysanus striolus Fallen. One specimen September 5.
Driatura gammaroidea Van Duzee. Fairly common, July.

Taken in timothy field in which there was an abundance

of ragweed.
Driatura gammaroidea var. flava Osborn and Ball. Sometimes

found with the preceding species.

354

June, 1916] Additions to the Jassoidea of Missouri 355

Lonatura catalina Osborn and Ball. Found in grassy meadow-
August 22.
Acinopterus acuminatus Van Duzee. Specimen in the collection

dated August 24. No food plant noted.
Eutettix cincta Osborn and Ball. Swept from undergrowth in

shady woods Records for June, July, August, September.
Eutettix subaenea variety querci Gillette and Baker. Common

on Black Jack brush.
Eutettix jucunda Uhler. Seldom taken.
Eutettix nigridorsum Ball. Occasionally on oak brush.
Eutettix johnsoni Van Duzee. R.are. One specimen Sept. 1.
Phlepsius excultus Uhler. Collected July 20, 1914.
Phlepsius altus Osborn and Ball. Everywhere common.

Occurring throughout the summer on oak brush.
Phlepsius sp. Taken in August. " Near truncatus but not like

my specimen under that name and not known to me."

Osborn.
Scaphoideus unicolor Osborn. In sweeping shrubs along fence

rows during July.
Thamnotettix fitchii Van Duzee. A specimen was secured

vSeptember 5.
Thamnotettix kennicotti Uhler. Collected July 22. Not

common.
Empoasca alboneura Gillette. Common in station collection

with dates of July, August, September.
Dicraneura fieberi Low\ One specimen sweeping wild grape

vines July o.
Alebra albostriella Fallen. Taken at porch light June 20.
Typhlocyba obliqua variety dorsalis Gillette. Collected from

both wild and tame grapes, through July.
Typhlocyba obliqua variety noevus Gillette. From material at

porch light June 20.
Typhlocyba comes variety near vitifex. "Differs from any I

have in black spots on vertex." Osborn.

State University of Iowa.

STARCH IN APPLE TREES.

W. A. Price.

In the absence of reliable data and abundant literature upon
the subject of starch storage and its changes throughout the
year, I have undertaken experiments which I hope will shed
further light upon the problem. The changes in the living
tissues, the sap wood and particularly the bark, were found
unexpectedly complicated. A few of the typical conditions
may be given for which an explanation is not as yet attempted.
The presence of starch in the non-living tissue, the heart wood,
was studied in detail, believing the conditions found may have
an important bearing in explaining the very ready decay of
apple tree wood, in comparison with that of some other trees.

In case of the living tissue, sections about 20 mic. in thickness
were made at intervals of ten days in dormant season, and four
or five days during the growing season. The presence of starch
was determined, in the usual way, by the iodin test. Each
time, one-year old, or older, twigs were examined, both from
the higher and lower portions of the crown of the tree; and
beginning April 17th, the roots were examined.

This work was done at Ohio State University in the spring
of 1914, under the general direction of Prof. Wendell Paddock,
head of the Horticulture Department, and Mr. Forest B. H.
Brown of the Botany Department.

The following typical conditions were found:

Temper-
ature

Age

OF

Wood
Yrs.

Pith

Xylem

Bark

Date

Max.
F.

Min.
F.

i

Ray

Bast
Par.

Pri.
Cor-
tex

Phello-
derm

Jan. 9
Mar. 9
Mar. 19
April 24
May 14

42
32

26
77
G3

34
19
20
51
41

1-9

1-9

1-10

1-10

1-8

+
+
+
+
0

+
+
+
+
0

+
+
+
+

0

0

+
+
+
0

0

+
0

+
0

0

+
+
+

+

0

+
+
+
+

-f- = starch present. 0 = starch absent.

May 14, clear; March 9, partly cloudy; other dates, cloudy.

356

June, 1916]

Starch in Apple Trees

357

The conditions found on January 9th seemed typical for
most of the winter months up to March. The remaining four
sections show some of the many changes that were found from
that time to the unfolding of the leaves. On March 9th occurred
the first notable changes. As shown in the table, starch now
appears in the bark, which does not agree with the results
obtained by Gourley, Bulletin 9, New Hampshire Agricultural
Experiment Station, for the ray tissue of the bark appears
generally to show starch from this time (March 9) on during
the period of observation (June 4) .

Buds began swelling March 9 and opened on April 24, when
the leaves were unfolding. While the buds were not greatly
swollen, a great deal of sap was present. Also the grains of
starch were generally corroded in the pith, and, to a much
less extent, in the xjdem throughout the upper portion of the
crown. Twigs on the lower part of the crown indicated less
activity, showing scarcely any corroding of starch grains. The
first corrosion occurred in the one-year-old wood in the upper
portion of the crown. About two days later, the same changes
appeared in the lower portion of the crown. The starch began
disappearing in the wood parenchyma, then the rays, and
finally the pith, in the order named.

As before mentioned, changes appear first in the one-year-old
twigs, then later in the older portions of the branch, as shown in
the following table, made from a fifteen-year-old branch^on
May 1st:

Age
Yrs.

Pith

Xylem

Date

Ray

Wood
Par.

Bark

May 1 . . .

1

+

0

0

0

May 1 . . .

2

+

+

0

0

May 1 . . .

3

+

+

0

0

May 1 . . .

4

+

+

+

0

May 1 . . .

5

+

+

+

0

May 1 . . .

6

+

+

-f

0

May 1 . . .

7

+

+

+

+

May 1 . . .

8

+

+

+

+

358 The Ohio Journal of Science [Vol. XVI, No. 8,

Besides showing the order in which the tissues are emptied
of starch, it also shows how the process is delayed with the
age of the stem. Beyond the eighth year no change has taken
place by May 12th. Starch has nearly disappeared from all
tissues above ground, except the heart wood.

Thus far, the storage of starch in living branch wood tissues
has been considered. For the sake of comparison, sections from
the trunk of a tree, with apparently non-living heart wood at
the center, were now made. During the last week in January
a tree showing 54 annual rings was cut at a height of one foot
from the ground, and a series of starch tests made from outer
bark to pith along both radii of the diameter. Very little
starch was found in the bark. The sapwood just beneath the
bark contained a considerable quantity distributed in the wood
parenchyma and medullary rays, but mostly in the rays. The
amount diminished inward from the bark gradually to the 12th
year, then suddenly, from which point no starch was regularly
found in the wood parenchyma, except at certain intervals to
be described later. From the 23rd year, the wood had the dark
brown heart wood color; here starch still occurred in the ray
cells, but intermingled with empty cells. At certain intervals,
23rd, 37th and 51st annual rings, occurred places where the
storage tissues, both rays and wood parenchyma, were densely
filled with starch, particularly in the summer wood portion of
the ring. Such starch accumulations in the heart wood may
possibly be explained on the assumption of "excess storage";
i. e., years when conditions were favorable for the production
and storage of starch, followed by a fruitless, or partly fruitless,
season. Inasmuch as fruit production is probably one of the
principal sources of starch consumption in the tree, one can
readily see that a condition of abundant supply would exist
with little provision for an outlet, and hence account for the
accumulation of starch in the heart wood. The fact that more
or less starch is stored in the annual rings throughout the
heartwood, and is not used from year to year, but simply
remains in the heart wood intact during the life of the tree,
suggests a reason for the decay of the trunk and the inner parts
of the larger Hmbs of the apple tree. It is well known that
starch is one of the best foods for the nutrition of fungi, and
when once the spores get access to the stored starch in the
heartwood, it is only a short time until the spread of the fungus

June, 1916] Starch in Apple Trees 359

reaches other portions, causing decay of the plant tissues, and
very soon the body of the tree becomes a shell. The sap wood
remains actively engaged in the functions necessary to the life
of the tree, and fungi do not so easily get hold. This gives us
the shell condition of the apple tree, which is so common in old
orchards where wounds to the tree are neglected, and incident-
ally, artificial roadways made to the heartwood of the tree for
the access of fungi.

In summary, it ma}^ be stated that, during the dormant
period, starch reserve is stored in the living cells of the pith,
wood parenchyma, and medullary rays of the apple. With
approach of spring, starch is found in the tissues of the bark,
appearing first in the phelloderm and collenchyma.

As the leaves begin to appear, starch begins to disappear
from the various tissues in order as follows: bark, wood
parenchyma, rays, pith. It is used first from the youngest wood
of the branches in the top of the tree, later, from the lower
portions of the tree, and finally from the roots.

A portion of the starch reserve may never be used in the
growth of the tree, but remains behind to be included in the
heartwood where it remains indefinitely and renders the wood
susceptible to decay.

Purdue University.

A GENERAL SYSTEM OF FLORAL DIAGRAMS.

JOHX H. SCHAFFNER.

Diagramatic representations of flowers are of great con-
venience in assisting one's memory in respect to floral structions,
especially when comparative and evolutionary studies are
undertaken. Such diagrams have been in use for a long time
and are found in most botanical text books and systematic
works. However, as usually constructed they are rather
vague and of various designs, which makes it difficult to employ
them in any exact way. The writer has devised a system by
which most of the essential structures of any flower may be
represented by a single transverse diagram, which at the same
time indicates in a general way the degree of advancement of
the flower in the evolutionary series.

There are five general types of flowers which call for definite
diagramatic representation, as follows:

1. Hypogynous flower, as in the lily.

2. Perigynous flower with a free hypanthium, as in the rose.

3. Perigynous flower with adnate hypanthium, as in the
apple.

4. Epigynous flower without hypanthium, as in the
honeysuckle.

5. Epigynous flower with hypanthium, as in the evening
primrose.

The various signs used are as follows: carpel, a small circle
(Fig. 1 a) ; vestigial carpel, the same in black (Fig. 1 b) ; axis
of inflorescence, a circle with a dot in the center (Fig. 1 c) ;
stamen, a pair of circles or figure eight without a line through
the center if the anther has but two microsporangia or with a
line through the center if it has four microsporangia (Fig. 1 d) ;
vestigial stamen, the same in black (Fig. 1 e) ; united carpels,
a large circle with radii to represent the partition walls, (Fig.
1 f) ; united carpels forming a unilocular ovulary, a similar
circle with points on the inside to represent the place of union
of two contiguous carpels (Fig. 1 g) ; sepal, a curved line,
thickened in the middle (Fig. 1 h) ; petal, a curved line thickened
in the middle and with a prominent point (Fig. 1 i). A necter
pit or spur is represented as shown in Fig. 1 j. Bracts are

360

June, 1916] A General System of Floral Diagrams 361

represented by curved lines of uniform thickness. The empty
glumes and flowering glumes of grasses, on account of their
importance, call for special treatment. The empty glumes are
represented simply like a pair of bracts, but the lemma receives
a narrow point at the middle projecting outward and the
palet two such points, one on either side of the middle and some
distance apart.

In representing spirals no attempt is made to show the
"pitch," or irregularities. Only the average number of spirals
with the number of parts in each, is shown, as in figures 2 and 3.
Usually only one spiral line is drawn, as in Figure 3, which
represents a cone with five spirals, with seven carpels in each
spiral. Fig. 2 represents a cone with three spirals, each with
nine carpels and all spiral lines represented.

Aside from representing the spiral curves, the diagrams can
be made with a pair of compasses and ruler and finished in
detail with a pen. Of course, many peculiarities may be
added without detracting from the definiteness or clearness
of the formal signs.

Figure 4 represents an ordinary hypogynous, actinomorphic,
pentacyclic, trimerous flower with united carpels, like a Yucca or
lily. If each petal sign were joined at its ends by a straight
line to the sepal sign, the diagram would represent a flower
like the lily-of-the- valley (Convallaria) . In general, connecting
lines mean union with or position on an organ.

Figure 5 represents a perigynous, zygomorphic pentacyclic
flower with united sepals. The hypanthium is represented by a
heavy dotted circle. Sepals, petals and stamens are shown
situated upon this by the connecting lines. Nine of the stamen
filaments are united, but one is free, showing plainly a dia-
delphous andrecium. The single free carpel is represented
in the center and the slight adhesion of one pair of petals is
shown by a dotted connecting line. In general, it is con-
venient for comparison to place all the diagrams with the odd
sepal on top. The relation of the flower to the axis of inflores-
cence can then be shown by placing the proper sign above or
below the diagram.

Figure 6 represents the diagram of an apple, in which the
perigynous hypanthium is grown together with the ovulary.
This is represented by filling in the space between the two with
dots. The sepals and petals are on the hypanthium and are

362 The Ohio Journal of Science [Vol. XVI, No. 8,

therefore connected with it by Hnes. The stamens are also
on the hypanthium and properly should also be connected
with it by lines, but as they are sometimes very numerous,
these lines may be omitted for convenience; since the position
of the stamens between the perianth and the hypanthium
necessarily implies that they are situated on the latter organ.
The best rule to follow in this respect perhaps is that where the
stamen are few in number and the lines can be drawn con-
veniently the connections should be made, but where they are
very numerous, the connecting lines may be omitted, pro-
vided that they are shown with the parts of the perianth.
The same procedure would be followed in epigynous types,
either with or without hypanthium.

The epigynous type of flower with an epigynous hypanthium
is represented in Figure 7. The representation of this type
is the same in general as in the perigynous flower, but the
hypanthium is connected with the ovulary wall by lines showing
its superior position. The ovulary wall is shown with a heavy
line in all epigynous types. This is merely to make the diagram
more striking when compared with the hypogynous type and is
not absolutely necessary since the epigyny is definitely shown
by the connecting lines. Diagram seven represents Fuchsia,
the four black oval spots inside of the hypanthium indicating
four glands.

The epigynous flower without hypanthium is shown by
figure 8, which represents Houstonia ciliolata. The calyx is
composed of united sepals and the corolla of united petals.
The stamens are distinct, but their filaments are united with
the corolla. This is indicated by the line connecting the
anther signs with the corolla sign. The lines connecting the
anthers with the ovulary represent the epigyny of the stamens
and the same is shown for the calyx and corolla. Extreme
reductions and specialization like the pappus of the dandelion
may be represented by a circle of dots.

In many cases it is possible to represent other structural
details in connection with the usual floral organs, but nothing
should be added that will obscure the real representation of the
important and fundamental morphology of the flower. If
properly and consistently constructed, such a series of flower
diagrams will be found a great aid in any study of comparative
morphology or evolutionary series.

Ohio Journal of Science.

\'oi,. XVI, Plate XXVII.

o • © $ t

John H. Schaffner,

364 The Ohio Journal of Science [Vol. XVI, No. 8,

EXPLANATION OF PLATE XXVIL

Fig. L The conventional signs used to represent the ordinary flower parts.

a. Carpel.

b. Vestigial carpel.

c. Axis of inflorescence.

d. Stamen.

e. Vestigial stamen.

f. United carpels, plurilocular ovulary.

g. Unilocular ovulary with three carpels,
h. Sepal.

i. Petal.

j. Petal with nectar cup.

Fig. 2. Diagram of carpellate cone of Tsuga canadensis, with three spirals.

Fig. .3. Diagram of carpellate cone of Sequoia washingtoniana, with five spirals,
only one traced out.

Fig. 4. Diagram of hypogynous flower of Yucca filamentosa.

Fig. 0. Diagram of perigynous flower of Lathyrus odoratus.

Fig. 6. Diagram of perigynous flower of Malus malus, with adnate hypanthium.

Fig. 7. Diagram of epigynous flower of Fuchsia, with epigynous hypanthium.

Fig. 8. Diagram of epigynous flower of Houstonia ciliotata.

Ohio State University.

INDEX TO VOLUME XVI.

Academy of Science, Ohio, 109.

Africa, South, Homoptera, 161.

Agallia, 180.

American Chemist and War's Prob-
lems, 219.

Apple Trees, starch, 356.

Athj^sanus, 187.

Anatomy, Jassoidea, 299.

Biemiller's Cove, sunfish nests, 125.

Boundary, Ordovician — Silurian, 329.

Bromides, spectra, 118.

Carbonaceous material in Monroe for-
mation, 155.

Caryomyia, 43.

Cave, Reames, 209.

Cecidiomyia, 37, 43, 269.

Cedar Point marsh, evaporation, 91.

Cedar Point, Toledo, 216.

Celtis occidentalis, zoocecidia, 249.

Cephalelus, 184.

Chemist, American, 219.

Chlorides, spectra, 117.

Cicadula, 195.

Constitution, Ohio vState Univ. Sci.
Soc, 32.

Cordia, 173.

Debarya, 18.

Deltocephalus, 186.

Derived solutions, diflferential equa-
tions, 231.

Diagrams, floral, 360.

Differential equations, derived soki-
tions, 231.

Dipterous galls, 268.

Electrical behavior, porcelain and glass,
81.

Electrical conductivity, indium and
thallium, 244.

Empoasca, 197.

Epibranchial placodes, 336.

Equations, differential, 231.

Eriophyes, 43.

Eriophves on Celtis, 256.

Eriophyidae, 37, 256.

Evaporation and Plant Zones, 91.

Exhibit cases, 105.

Floral diagrams, 360.

Galls, insect, 37, 249.

Geometry, translated normal curve, 60.

Glass, electrical behavior, 81.

Greenfield member, Monroe formation,
155.

Halogen compounds, spectra, 113.

Hemipterous galls, 259.

Hexagon notation, 135.

Hicoria, Zoocecidia, 37.

Homoptera of South Africa, 161.
Homopterous studies, 161, 299.
Idiocerus, 180.

Indium, electrical conductivity, 244.
Introductory, 1.
Insect galls, 37, 249.
Iodides, spectra, 116.
Itonididae, 37, 268.
Jassoidea, 161.
Jassoidea of Missouri, 3.54.
Jassoidea of Missouri, list, 71.
Jassoidea, Morphology, 299.
Leafhoppers, 161.
Leptostyla costofasciata, 326.
Locris, 170.
Macropsis, 178.

Making photographic objective, 3.
Maxville limestone, outliers, 151.
Missouri, Jassoidea, 71, 247, 354.
Mite gall, 37.

Monroe formation, carbonaceous ma-
terial, 155.
Morphology, Jassoidea, 299.
Morphology, Zoocecidia, 249.
Nests, sunfish, 125.
News and notes, 79, 247.
Normal curve, translated, 60.
Notes on Zygnemales, 17.
Nutrients, renewal in sand cultures, 101.
Objectives, photographic, 3.
Ohio Acad, of Science, 109.
Ohio Maxville limestone, 151.
Ohio State University Sci. Soc, 32.
Ohio va.scular plants, additions, 104.
Ordovician — Silurian boundary, 329.
Outliers, Maxville limestone, 151.
Pachypsylla on Celtis, 260.
Pediopsis, 179.
Penthimia, 182.
Philaenus, 175.
Photographic objective, 3.
Phytophaga, 271.
Placodes, epibranchial, 322.
Plant disease exhibit cases, 105.
Plants, Ohio, 104.

Plant zones, in Cedar Point marsh, 91.
Poophilus, 176.

Porcelain, electrical behavior, 81.
Reames cave, 209.
Rhinaulax, 169.

Sand culture, renewal of nutrients, 101.
Silurian-Ordovician, boundary, 333.
South Africa, Homoptera, 161.
Spectra, halogen compounds, 113.
Sphaerometer for short radii, 15.
Spirogyra, 23.

365

Index to Volume XVI

Squalus acanthias, epibranchial, pla- Translated normal curve, 60.

codes, 336. Typhlocyba, 198.

Starch in apple trees, 356. Vascular plants, Ohio, 104.

Sunfish nests, Biemiller's cove, 125. Zones, plant, and evaporation, 91.

Tennessee tingid, 326. Zoocecidia on Hicoria, 37.

Thamnotettix, 192. Zoocecidia, morphology, 249.

Thallium, electrical conductivity, 244. Zygnemales, 17.
Tingid, new, 326. Zygnema, 21.

Toledo Cedar Point, 216.

NEW SPECIES DESCRIBED IN VOL. XVI

Animal

Agallia cuneata Cog 181

Agallia nigrasterna Cog 180

Athysanus aethiopica Cog 189

Athysanus cyclopia Cog 191

Athysanus eriocephalus Cog 190

Athysanus nemesia Cog. 191

Cicadula longiforma Cog 196

Deltocephalus aristida Cog 187

Deltocephalus breviatus Cog 186

Empoasca heliophila Cog • 197

Empoasca protea Cog 197

Idiocerus hewitti Cog 180

Leptostyla costofasciata Drake 326

Pediopsis capensis Cog 179

Philaenus hottentoti Cog .-.:....;.. 175

Thamnotettix cotula Cog 193

Thamnotettix karrooensis Cog 192

Thamnotettix karrooensis pallidus Cog 192

Thamnotettix pentzia Cog 194

Thamnotettix struthiola Cog 194

Typhlocyba elegia Cog 199

Typhlocyba mallyi Cog 198

Typhlocyba purpureatincta Cog 198

Plants

Debarya americana Trans 18

Debarya decussata Trans 19

Debarya glyptosperma formosa Trans 18

Spirogyra borgeana Trans 23

Spirogyra crassa formosa Trans 27

Spirogyra farlowii Trans .' 29

Spirogyra floridana Trans 30

Spirogyra hydrodictya Trans 28

Spirogyra micropunctata Trans 27

Spirogyra nova-angliae Trans 26

Spirogyra propria Trans 25

Spirogyra reflexa Trans 28

Zygnema cruciatum caeruleum Trans 21

Zygnema cylindricum Trans 22

Zygnema pectinatum crassum Trans 21

Date of Publication June 10, 1916.