THE OHIO
JOURNAL OF SCIENCE

(CONTINUATION OF THE OHIO NATURALIST)

Official Organ of the

OHIO ACADEMY OF SCIENCE

and of the

OHIO STATE UNIVERSITY SCIENTIFIC SOCIETY

. VOLUME XXII — 1921-22

OHIO STATE UNIVERSITY
COLUMBUS

A

S.f-0

AUTHOR INDEX.

Alexander, Wm. H 21

Braun, E. Lucy 99

Carman, J. Ernest 125

DoziER, H. L 69, 117

Drake, C. J 114

Gahan, a. B 140

Hanawalt, F. a 164

Hartley, E. A 209

HiNE, J. S 143

Hubbard, Geo. D 97, 193

Jones, O. C 193

Kennedy, C. H 84

Krecker, F. H 155

Osburn, R. C 158, 173

Rice, E. L 1

Schaffner, J. H 91, 101, 129, 149

Turner, C. L 41, 95

Weiss, Harry B 63

West, Erdman 63

Williams, Stephen R 170

Veth, Ruth M 158

1^1^

The Ohio Journal of Science

Vol. XXII November, 1921 No. 1

REPORT OF THE THIRTY-FIRST ANNUAL MEETING
OF THE OHIO ACADEMY OF SCIENCE

E. L. RICE
Secretary

The Thirty-first Annual Meeting of the Ohio Academy of
Science was held at Western Reserve University and Case
School of Applied Science, Cleveland, Ohio, March 25 and 26,
1921, under the Presidency of Mr. W. H. Alexander. Fifty-
nine members were registered as in attendance; forty-seven
new members were elected.

In accordance with the practice begun in 1918, but of which
discontinuance has since been threatened, a geological excursion
was organized by Professor J. E. Hyde, Vice-President for
Geology, 1921-22, for the three days, May 28, 29and-30. The
party was under the guidance of Drs. August Foerste and W. H,
Shideler. The itinerary (Wilmington, Clarksville, Fort Ancient,
Oregonia, Dayton) was planned for the study of the Richmond
formations of southwestern Ohio. Like other Academy func-
tions, the excursion was open to non-members as well as
members; fifteen geologists were present.

General Program.

Friday, March 25.

-Business Meeting.

-Reading of Papers in General Session.

-Luncheon.

-Demonstrations.

-Reading of Papers in General Session.

-Lecture by Dr. Henry H. Goddard, Bureau of Juvenile

Research, Columbus, on "Scientific Work at the

Bureau of Juvenile Research."
-Reading of Papers in General Session.
-Dinner.

9:30 A.

M.-

11:00 A.

M."

12:30 P.

M.-

2:00 P.

M.-

2:30 P.

M.-

3:30 P.

M.-

4:30 P.

M.-

6:30 P.

M.-

2 E. L. RICE Vol. XXII, No. 1

8:00 P.M. — Address by the President of the Academy, Mr. W. H.
Alexander, U. S. Weather Bureau, Columbus, on
"Thunder Storms: Especially Those of Ohio."

9:00 P. M. — ^Adjourned Business Meeting.

Saturday, March 26.

9:00 A. M. — Adjourned Business Meeting.

10:00 A. M. — Lecture by Professor Charles A. Kofoid, University of
California, Berkeley, California, on "Hookworm and
Htunan Efficiency."
11:00 A. M. — Reading of Papers in Sectional Meetings.
2:00 P. M. — Demonstrations.

Saturday, May 28 — Monday, May 30.
Excursion by Section for Geology.

Minutes of Business Meetings.

The first business session was called to order by President
Alexander at 9:30 A. M., on Friday, March 25. Adjourned
sessions were held after the presidential address on Friday
evening and at 9:00 A. M. on the following day.

The appointment of the following committees for the
meeting was announced by the chair:

Committee on Membership — F. C. Waite, E. L. Fullmer,
J. E. Hyde.

Committee on Resolutions — C. G. Shatzer, R. C. Osburn,
W. H. Bucher.

Committee on Necrology—]. E. Hyde.

The following Auditing Committee was elected by the
Academy: L. B. Walton, E. L. Fullmer.

The following Nominating Committee was elected by the
ballot of the Academy: F. H. Herrick, E. L. Fullmer, J, E.
Carman, F. C. Waite, H. H. Young.

Report of the Secretary.

The following report by the Secretary was received and
ordered filed:

March 22, 1921.
To the Ohio Academy of Science:

Much of the work of the Secretary is covered by the Report of
the Executive Committee.

Nov., 1921 ANNUAL MEETING — OHIO ACADEMY 0^ SCIENCE 3

The following brief note from Mr. McMilHn, in reply to the Secre-
tary's notification of election as patron and fellow, will be of interest
to the membership of the Academy and may well have a permanent
place in the records of the Academy:

Darlington, Mahwaii, N. J., July 3, 1920.
Dear Mr. Rice:

Your good letter of July 1st was received a few moments ago.
I thank the Society for all the honors they have conferred upon me,
and greedily accept them all.

Most sincerely yours,

Emerson McMillin.
Edward L. Rice, Sec'y, Ohio Academy of Science.

There has been some additional correspondecne with the National
Research Council concerning the research work of the Academy.

An appeal for the students of the Department of Geography of the
Hungarian University of Debreczen was received under date of Decem-
ber 7, and will be presented later in the meeting.

A brief report of the Thirtieth Annual Meeting was prepared for
Science, and appeared in the issue for August 6th.

In accordance with the instructions of the Academy, the Secretary
prepared the Constitution, as amended to date, for reprinting, and it
appeared in the Proceedings in connection with the Report of the
Annual Meeting.

A number of technical changes in the form of the membership list
were necessitated by the designation of fellows and national members
(i. e., Academy members who are also members of the American Asso-
ciation for the Advancement of Science). In this revision errors may
well have crept in; the secretary will be very grateful for corrections
of such mistakes in order that the next list may be made as accurate
as possible. Respectfully submitted,

Edward L. Rice, Secretary.

Report of the Treasurer for the Year 1920-21.

The report of the Treasurer was received as follows, and
referred to the Auditing Committee, whose report is appended.

Balance in Hayden-Clinton Bank, May 13, 1920, as previously

reported $ 363.90

Deposits 1,357.90

Total $1,721.80

Less checks 1,206.06

Balance in bank March 17, 1921 $515.74

4 E. L. RICE Vol. XXII, No. 1

The distribution of the fiinds expended is as follows :

To members of the Ohio Academy as refunds from the A. A.

A. S $ 46.00

To E. L. Rice, Secretarial expenses 12.51

To Independent Print Shop 53.25

To Spahr & Glenn, Printers 8.75

To Hiss Stamp Company 1.40

To James S. Hine for Ohio Journal of Science 500.00

To T. C. Mendenhall, for coupons from bond 4.15

To B. E. Livingston for A. A. A. S 580.00

$1,206.06
Cr.

Balance carried forward $ 363.90

Cash deposited 1,357.90

$1,721.80

Dr.

As itemized expenditures $1,206.06

Balance in hand 515.74

$1,721.80

The Treasurer feels that the Academy is on a sound financial basis
as is indicated in the report. He wishes to take this occasion to thank
the members of the Ohio Academy of Science for their cordial support.
There have been several cases of delays and misunderstandings in the
collection of the joint dues for the American Association for the Advance-
ment of Science and for the Academy. This is greatly to be regretted
but from a careful study of the methods of payment, the Treasurer
believes that the system will be practically automatic in another year.
In order to avoid all trouble and inconvenience, prompt payments
should be made in the early autumn when the bills are sent out. This
insures prompt notification of the subscription managers of Science
and of the Ohio Journal of Science and uninterrupted delivery of
the two journals. Unless the Treasurer has the unanimous co-operation
of the members in the matter of promptness, he cannot assure them of
immediate attention. He is at all times glad to have reports of errors or
delays and willing to do everything he can to adjust matters to the
satisfaction and convenience of the members. During the year the
present Treasurer has just served he has done practically all the work
of billing, dunning, and corresponding unaided. This was done, not so
much with the desire to save the slight cost of additional help, as in the
hope that he might come to know all the details of the job and espe-
cially to straighten out accounts of members in arrears. It is to be
hoped that members will take care of their arrearage sooner in the
future, but this matter, in the case of those member^ of the Academy
who are also A. A. A. S. members, will quickly adjust itself. In the
itemized account of the funds the deposits are somewhat swelled because
of arrearage. Because there is no adequate adjustment of this for the
Ohio Journal an increase to the Journal was given this year.

Nov., 1921 ANNUAL MEETING — OHIO ACADEMY OF SCIENCE 5

While this increase for the Journal comes at a time when it is
greatly needed, it should be clear in the minds of the members that
the Treasurer does not condone arrearages. A periodical journal can
not subsist on alternate fat and lean years. It is desirable that its
pabulum be more evenly distributed. Further the Treasurer is definitely
preparing to meet the future expansion of the Ohio Journal of Science.
He believes in it thoroughly and wishes to make it an adequate medium
of expression for all the members. The Journal ought to appeal
especially to the younger members of the Academy. They need to pub-
lish articles in order to become introduced to the older scientific workers.
The Treasurer feels that all the money that can be put into the Journal
is still not nearly enough to make it the best one of its kind in the
country. By making it attractive, the Journal can continue to publish
some of the best articles that the members of the Academy can write.

The Treasurer further wishes to call the attention of the members
to the fact that Mr. L. H. Tiffany of the Department of Botany of the
Ohio State University, has been appointed subscription manager of the
Journal. It is his duty to see that all members who have squared
accounts with the Treasurer be supplied with all numbers of the Jour-
nal to which they are entitled, without further charges. He is at
present attending to all cases of non-delivery of the Journal that have
come to his attention. All complaints in the matter of the delivery of
the Journal sent to Mr. Tiffany can now be cared for. It is thus to be
hoped that the members of the Academy will be promptly served.

Respectfully submitted,

A. E. Waller, Tresasurer.

We have examined the above report and found it to be correct.

Respectfully submitted,
L. B. Walton,
E. L. Fullmer,

Auditing Committee.

Report of the Executive Committee.

The report of the Executive Committee was received as
follows and ordered filed:

March 25, 1921.
To the Ohio Academy of Science:

A meeting of the Executive Committee was held in Columbus,
December 18, 1920; all members of the Committee were present.

An invitation was received from Western Reserve University and
Case School of Applied Science to hold the Annual Meeting for 1921 in
Cleveland. The Executive Committee voted unanimously to accept
this invitation, and set the date of the meeting for April 1 and 2. The
date was later changed by correspondence to Alarch 25 and 26, in order
to bring it within the spring recess of Western Reserve University.

6 E. L. RICE Vol. XXII, No. 1

The Secretary reported correspondence with Prof. R. C. Friesner,
Chairman of the Program Committee of the Indiana Academy of
Science, relative to the possibility of a joint field meeting of the two
Academies this spring. The joint meeting is rendered difficult by the
fact that the Indiana Academy holds a fall meeting for the presentation
of papers and a field meeting in the spring, while the Constitution of the
Ohio Academy restricts the Annual Meeting to March or April. A
joint meeting in the spring must either debar the Ohio Academy from
the opportunity^ for presentation of papers or eliminate the field meeting
from the program of the Indiana Academy. The Executive Committee
voted its general approval of a joint meeting at some future date, and
instructed the Secretary to continue negotiations with the Indiana
Academy. The Committee further instructed the vSecretary to give
notice to the Academy of a proposed amendment to the Constitution
removing the present restriction as to the date of the Annual Meeting,
unless such amendment shall prove to be contrary to the Charter of
the Academy.

The Executive Committee recommended to the Joint Committee
on the Election of Fellows that an opportunity be given this year for
the nomination of fellows by the present fellows of the Academy on the
lines suggested in the pending Constitutional amendment.

Professor Blake was requested to make an investigation of the
desirability of an affiliation of the Academy with the Ohio Association
of Technical Societies, as suggested in the Annual Meeting of 1919.

The President, Mr. Alexander, was requested to act as Chairman of
the Committee on Legislation during the absence of Professor Osborn.

A second meeting was held in Cleveland on the evening of March 24,
at which this report was adopted. The President, Treasurer and Secre-
tary were present at this meeting.

Thirty-six new members have been elected during the year, subject
to the ratification of the present meeting.

Edward L. Rice, Secretary,

For the Committee.

Report of the Publication Committee.

The following report of the Publication Committee was
received and ordered filed:

The Annual Report of the Thirtieth Meeting (Proc. Ohio Acad. Sci.,
Vol. VII, Part 5, pp. 117-158) was published on January 17, 1921. It
contains the Constitution and By-Laws in addition to the usual matter.
Fifty reprints each of the list of members and of the Constitution were
also printed. The present arrangement of printing the Secretary's
report in the November issue of the Ohio Journal of Science fol-
lowed soon after by the complete annual report seems satisfactory.

Respectfully submitted,

John H. Schaffner, Chairman.

Nov., 1921 ANNUAL MEE:TING — OHIO ACADEMY OF SCIENCE

Report of Library Committee.

A brief report for the Library Committee was prepared for
the meeting by Mr. Reeder; but, owing to a delay in the mail,
this report was not received by the secretary until after the
close of the meeting. The following report has since been
received for publication.

March 23, 1921.
To the Ohio Academy of Science:

The Library Committee begs leave to submit the following report :

(1) The sale of publications during the year has amounted to $1295.

(2) The Proceedings of the 30th annual meeting of the Academy
were published in the Ohio Journal of Science for November, 1920.
Reprints were received late in February and copies were mailed imme-
diately to all persons on the membership roll and to sixty-eight insti-
tutions on the exchange list.

(3) The University Library again calls to the attention of the
Academy its willingness to lend to any member, through his institu-
tional library, any publication needed in research work. The library is
receiving the exchanges from the Ohio Academy and from the Ohio
Journal of Science, and together with its own purchases and collec-
tions in the scientific fields, there is available a remarkable source of
literature for advanced study and research. It is hoped that more use
will be made of these sources by the scientific men of Ohio.

Very respectfully,

C. W. Reeder.

Report of the Trustees of the Research Fund.

The following report of the Trustees of the Research Fund
was received and ordered filed. The financial portion of the
report was referred to the Auditing Committee, whose report
is appended.

To the Ohio Academy of Science:

The Trustees of the Research Fund submit the following report
for the period from May 12, 1920, (the date on which the last report
was made), to March 1, 1921.

During this period only two payments from the fund were made : To
L. B. Walton, the balance of the grant made to him in 1917, for the
study of fresh water organisms; to Miss Elsie Jordan, for a contin-
uation of the work of relabeling the Harper collection of Naiades, under
the direction of W. H. Beecher, to whom the grant was made.

Unexpended balances remain to the credit of A. E. Waller, for the
study of Ohio vegetation, and to W. H. Bucher, for aid in the making
of a geological map of the disturbed area in Adams County, Ohio.

8 E. L. RICE Vol. XXII, No. 1

A grant of $150 was made on January 10, 1921, to W. J.. Koster, to
aid in a survey of the Orthopteran fauna of Ohio.

Correspondence is in progress which may lead to a renewal of the
grant made to Paul B. Sears on June 1, 1819, and a further allotment
to W. H. Bucher, for the continuation of work originally undertaken by
them.

Below is a tabulated statement of receipts and expenditures during
the period covered by this report. In this, it will be noted, is included
a one hundred dollar Liberty Bond received from the Treasurer of the
Academy to be added to the Research Fund and which is held as a
more or less permanent investment along with that purchased in 1918.
The accrued interest on both of these bonds is added to the active
assets of the funds.

At present the amount available for allotment is $569.96, from which
it will appear that the demand for the somewhat restricted financial aid
to research which this fund furnishes has not been very great during
the past year.

Vouchers for all expenditures are submitted herewith, together
with the Cashier's certificate of the balance in the bank on March 1, 1921.

RECEIPTS.

Cash in bank May 1, 1920, as per report of that date. .$644.68
Interest on new Liberty Bond, May 15 and July 28, 1920 6 . 27

Interest on Libertv Bonds, Feb. 23, 1921 12. 76

Check from Mr. W. Gluttin, Feb. 23, 1921 250.00

$913.71

EXPENDITURES.

Elsie Jordan, June 19, 1920 $22.50

L. B. Walton, January 7, 1921 20.31

42.81

ASSETS.

Cash in bank, March 1, 1921 870.90

Total Assets, Liberty Bonds at par $1,470.90

LIABILITIES (under GRANTS)

A. E. Waller $ 75 . 00

W. H. Bucher 75 . 94

W. J. Koster 150.00

$300.94

Excess of Available Assets over Liabilities $569 . 96

(Signed) T. C. Mendenhall, Chairman.
Herbert Osborn.

We have examined the report and found it to be correct.

L. B. Walton,
E. L. Fullmer,
March 25, 1921. Auditing Committee.

Nov., 1921 ANNUAL MEETING — OHIO ACADEMY OF SCIENCE 9

Report of Committee on Legislation.

Professor Herbert Osborn, chairman of the Committee on
Legislation, submitted the draft of a proposed bill looking to
recognition and financial support of the Academy by the State.
The bill, as submitted, is modeled after that establishing the
State Archaelogical Society. It was written by Mr. Edge,
official "bill drafter" for the Assembly, in consultation with
President Alexander, who acted as chairman of the Committee
during Professor Osborn's absence from Ohio.

After extended discussion, the report was adopted by the
Academy, with minor amendments of the bill, and the Com-
mittee was continued with instructions to carry on the cam-
paign. President Alexander was added to the Committee,
which, as now constituted, consists of the following: Herbert
Osborn, chairman; W. H. Alexander, T. C. Mendenhall, M. M.
Metcalf, E. L. Rice, L. B. Walton.

The Committee was instructed to draft such revision of the
Constitution of the Academy as may be necessary in case the
bill is passed by the Assembly, this action to be interpreted as
notice of amendment of the Constitution and as enabling the
Academy to take final action at the next annual meeting.

The proposed bill, including the amendments voted by the
Academy, follows:

A Bill

Relative to State recognition of the Ohio Academy of Science.

Be it Enacted by the General Assembly of the State of Ohio:

Section 1. The Ohio Academy of Science, a corporation not for profit,
incorporated under the laws of Ohio, March 12, 1892, shall be under the control
of a board of trustees consisting of fifteen members to serve without salary or per
diem. Six of the members of the board shall be appointed by the governor with
the advice and consent of the Senate, two to serve for two years, two to serve for
four years and two to serve for six years, and until their successors are appointed
and qualified, and thereafter two members shall be appointed every two years
to serve for a term of six years. The remaining nine members of the board shall
be elected by the members of the Academy.

Section 2. On and after the passage of this act, the Ohio Academy of Science
shall constitute an official source of advice and information on all scientific ques-
tions within its field submitted to it by any state department or officer thereof.
The services of the Academy shall be available to the state or any of its officers in
any matter within its field in which the consideration of scientific facts or policies
may be involved, and the officers of the state may call upon the Academy of
Science, through its properly elected officers or committees appointed by its
officers, for such consultation and advice as may be of service to them in their
duties. The members of such committees shall receive no compensation for their
services, except that all traveling, clerical and other necessary expenses shall be

10 E. L. RICE Vol. XXII, No. 1

paid. No member of the Ohio Academy of Science, while serving on any such
committee, shall be eligible for expert service under advice from said committee
for which compensation from the state is received.

Section 3. One copy of the "Proceedings of the Academy" shall be dis-
tributed to each public library and museum, university, college, normal schools,
and first grade high school in the state, and one copy of each number of its official
organ, "The Ohio Journal of Science," shall be distributed to each university
and college in the state. All exchanges received shall be kept available to the
citizens of the state through the library of The Ohio State University, or such
other channel as may be determined.

Section 4. The secretary of the Ohio Academy of Science shall be a person
well suited by training and experience to perform his duties and may be paid from
state funds.

Section 5. The legislature shall make such appropriations from year to
year as may be necessary to print the official publications of said Academy and to
carry out the other provisions of this act.

Report of Committee on Preservation of Wild Life
of State.

In addition to an oral report by the chairman concerning
the conservation work already accomplished in Ohio and other
states, the Committee presented the following formal recom-
mendations. The recommendations were adopted by the
Academy, and the Committee continued under the changed
name suggested: Committee on State Parks and Conservation.

The Committee on Preservation of Wild Life of State would
recommend :

(1) That the present Committee be continued as a Coinmittee on
State Parks and Conservation, to study the various problems involved
and to report a matured plan for further action by the Academy.

(2) That all members co-operate in listing suitable tracts for use
as state parks, bird reserves, and reservations for the permanent
preservation of areas possessing scenic, geologic, or biologic interest.

(3) That the committee proceed to secure co-operation with exist-
ing organizations in the preservation of natural conditions in the state
forests, game refuges, state controlled tracts, and other areas where
such co-operation is possible.

Herbert Osborn,
J. Ernest Carman,
Francis H. Herrick,
C. G. Shatzer,
E. N. Transeau,
Maynard M. Metcalf,
Committee.

Report of Committee o?i Election of Fellows.

The following report of the Committee on Election of
Fellows was accepted and ordered filed:

Nov., 1921 ANNUAL MEETING — OHIO ACADEMY OF SCIENCE 11

March 2o, 1021.
To the Ohio Academy of Science:

The method of work of the Committee on the Election of Fellows
has been as follows:

(1) Throu(];h the preliminary announcement of this meeting, the
entire membership of the Academy was given the opportunity to make
nominations for fellowship. A single nomination was received.

(2) Copies of the membership list were mailed by the Secretary
to the eleven members of the joint committee to be checked as nom-
inating ballots. Nine ballots were returned. Five members received
three ballots each, four received two ballots, and thirty-four received
one ballot.

(3) A meeting was held in Cleveland on the evening of March 24th,
at which seven members of the joint committee were present, two were
represented by duly authorized proxies, two were absent without
representation.

After careful consideration and discussion, seventeen members
received the necessary nine votes and were declared elected to fellow-
ship in the Academy. The newly elected fellows will be personally
notified, and the list will appear in the Proceedings.

In addition to the constitutional specification of "productive scien-
tific work" as a condition for fellowship, the committee has been guided
by the . following principles, which it recommends as a general policy
for future action:

(1) Members should not be elected to fellowship in the Academy
until one year, at least, after election to membership.

(2) Resident members should not be elected to fellowship who
are not showing an active interest in the work of the Academy.

This year's committee, like that of last year, took the ground that
its action should be conservative. It is probable that good candidates
for fellowship have been passed over; it will be the duty of future
committees to correct these omissions.

Respectfully submitted,

Edward L. Rice, Secretary.,

For the Committee.

The list of members elected to fellowship is as follows:

G. F. Arps Wm. E. Henderson

H. H. M. Bowman J. S. Houser

E. Lucy Braun James Ernest Kindred

Harold E. Burtt Sidney Isaac Kornhauser

DwiGHT M. DeLong Florence Mateer

Carl Dr.\ke H. C. Oberholser

Wm. Lloyd Evans Paul B. Sears

Emery R. Hayhurst Victor Sterki
B. W. Wells

12 E. L. RICE Vol. XXII, No. 1

Election of Officers.

The following officers and committee members for 1921-'22
were elected by the ballot of the Academy :

President — Professor R. C. Osburn, Ohio State University, Columbus.
Vice-Presidents:

Zoology — Dr. J. E. Kindred, Western Reserve University,

Cleveland.
Botany — Professor E. N. Trans eau, Ohio State University,

Columbus.
Geology — Professor J. E. Hyde, Western Reserve University,

Cleveland.
Physics — Professor W. G. Hormell, Ohio Wesleyan University,

Delaware.
Medical Sciences — Professor F. C. Waite, Western Reserve Uni-
versity, Cleveland.
Psychology — Professor Rudolph Pintner, Ohio State University,
Columbus.

(Professor Pintner later resigned the Vice-Presidency,
owing to removal from the state, and

was appointed by the Executive Com-
mittee to fill the vacancy.)
Secretary — Professor E. L. Rice, Ohio Wesleyan University, Delaware.
Treasurer — Dr. A. E. Waller, Ohio State University, Columbus.
Elective Members of Executive Committee — Mr. W. H. Alexander, U. S.
Weather Bureau, Columbus; Professor L. B. Walton, Kenyon
College, Gambler.
Member of Publication Committee — Professor L. G. Westgate, Ohio

Wesleyan University, Delaware.
Trustee of Research Fund — Dr. T. C. Mendenhall, Ravenna.
Member of Library Committee — Professor W. C. Mills, Ohio State

Universit3^ Columbus.
Representatives on Editorial Board of Ohio Journal of Science:

Zoology — Professor R. A. Budington, Oberlin College, Oberlin.
Botany — Professor Bruce Fink, Miami University, Oxford.
Geology — Professor G. D. Hubbard, Oberlin College, Oberlin.
Physics — Professor S. J. M. Allen, University of Cincinnati,

Cincinnati.
Medical Sciences — Professor F. C. Waite, Western Reserve Uni-
versity, Cleveland.
Psychology — Professor H. A. Aikins, Western Reserve University,
Cleveland.

Nov., 1921 ANNUAL MEETING — OHIO ACADEMY OF SCIENCE 13

Election of Members.

The Membership Committee reported eleven names for
election to membership ; thirty-six additional names, previously
approved by the Executive Committee and marked with (*) in
the following list, were presented for ratification. All were
elected, as follows:

*AiNSLEE, Geo. G.; Entomology; U. S. Entomological Laboratory,

R. D. 9, Knoxville, Tenn.
Altaffer, L. B., Chemistry; 7013 Clinton Ave., Cleveland.
*Bean, Raymond Jackson; Physiology, Embryology; Biological

Laboratory, Western Reserve University, Cleveland.
*Chase, Samuel Wood, Zoology; 1353 E. 9th St., Cleveland.
*Chassell, Laura M., Psychology; Dept. of Psychology, Ohio State

University, Columbus.
*Clayton, Edward E.; Botany; Botany and Zoology Bldg., Ohio

State University, Columbus.
*Dever£Aux, W. C. ; Meteorology; Weather Bureau Office, Cincinnati.
*Dobbins, R.A.YMOND A.; Botany, Entomology; Dept. of Botany,

Ohio State University, Columbus.
*DoCKERAY, F. C; Psychology; Ohio Wesleyan University, Delaware.
*Emery, E. H. ; Meteorology; 829 Society for Savings Bldg., Cleveland.
*Friedlander, Mae; Bacteriology, Biology; 343 Carroll St., Akron.
*GoDDARD, Henry H.; Psychology, Sociology; 1638 Granville St.,

Columbus.
*Hartley, Edwin A. ; Entomology; Dept. of Zoology and Entomology,

Ohio State University, Columbus.
*Hayhurst, Emery R. ; Medical Sciences; Dept. of Public Health and

Sanitation, Ohio State University, Columbus.
Hills, Myra E.; Psychology; 2066 E. 100th St., Cleveland.
*Jones, J. W. L. ; Psychology; Heidelberg University, Tiffin.
*Knouff, Ralph A.; Medical Sciences; Ohio State University,

Columbus.
*LuCKEY, Bertha M.; Psychology; Board of Education, Cleveland.
*M ANSON, Edmund S., Jr.; Astronomy, Physics, Mathematics; Ohio

State University, Columbus.
*Marshall, Helen; Psychology; Ohio State University, Columbus.
Martin, John R. ; Physics; Dept. of Physics, Case School of Applied

Science, Cleveland.
Mather, KiRTLEY F.; Geology; Denison University, Granville.
Moore, Dwight M.; Botany; Granville.
*Morse, Paul Franklin; Geology; Asst. State Geologist, Jackson,

Miss.
*Moxom, Walter J.; Meteorology, Phj-sics, Psychology; U. S.

Weather Bureau Office, Dayton.
*Murchison, Carl; Psychology; The Tallawanda, Oxford.

14 E. L. RICE Vol. XXII, No. 1

*Myers, Garry C; Psychology; Cleveland School of Education,

Cleveland.
NiEH.\us, Wm. E.; Zoology, Geology; Berea.
*Olin, Oscar E.; Psychology, Sociology; University of Akron, Akron.
*Patten, Bradley M.; Zoology, especially Embryology; 1353 E.

Ninth St., Cleveland.
*Patton, Leroy; Geology; Muskingum College, New Concord.
*Rea, Paul M.; Natural History Sciences, especially Zoology; The

Cleveland Museum of Natural History, Cleveland.
Riley, C. L.; Biology, Geology; 1219 Logan Ave., N. W., Canton.
*RooTS, Yale K.; Physics; 412 N. Walnut St., Wooster.
Ross, Herbert W.; Chemistry, Geology; West Technical High

School, Cleveland.
*Sayre, Jasper D.; Botany; Dept. of Botan\^ Ohio State University,

Columbus.
*Skaggs, Ernest B.; Psychology; 23 S. Union St., Delaware.
Smith, Ella Thea; Botany, Zoology; P. O. Box 7, Salem.
Smith, Ernest Rice; Geology, Paleontology; 130 Woodland Ave.,

Oberlin.
*Stone, Julius F., General Science, Grandview, Columbus.
*Strausbaugh, p. D.; Botany, Microchemistry as applied to Plant

Phvsiologv; Burbank Road, R. F. D. 10, Wooster.
TippiE, William A.; Physics; 2145 W. 100th St., Cleveland.
*Watson, a. C; Psychology; Marietta College, Marietta.
*Webb, Robert Fulton; Geology; Dept. of Geology, Ohio State

University, Columbus.
*Williams, R. D.; Philosophy, Psychology; Dept. of Philosophy,

Ohio State University, Columbus.
*WuRDACK, Mary E.; Botany; 29 Twelfth Ave., Columbus.
*YouNG, Herman H.; Psychology, Educational Research; 235 Chapel

Place, Youngstown.

Report of Committee on Necrology.

The following report of the Committee on Necrology was
adopted by the Academy and ordered filed.

Thomas Piwonka.
September 10, 1854— May 9, 1920.

I first met Thomas Piwonka on the field excursion of the Academy
for geology in May, 1919. The failing sight and frailty of age prevented
him from participating in full, and he carefully withheld himself from
much of the trip that he might not in any way impede the progress of
the party. This thought for others was characteristic.

This was less than a year before his death. I saw him but six or
eight times in the interval, but these meetings brought us together on
the Cleveland shale outcrops of Big Creek which he had often searched
for Devonian fish, in his own study and in my laboratory. There are

Nov., 1921 ANNUAL MEETING — OHIO ACADEMY OF SCIENCE 15

few men that it is possible to know on so short an acquaintance, yet
due to a common interest in fossils. I may, I believe, fairly claim to
have attained a certain intimacy with him.

It began when he modestly offered to go with me and show me, if I
cared to have him, the localities where Dr. Clark, of Berea, had been
most successful in his search for fossil fish. "If I cared!" To me, it is
an opportunity forever lost that I was able to visit only one locality
with this man who had been the intimate companion of Dr. Clark, the
indefatigable collector, and Edward Claypole, the elucidator, of the
Cleveland shale fish.

With the same modesty, almost with depreciation lest he might
seem to intrude himself, he invited me to look over his small collection
of fossils from the Cleveland district. When he learned that Western
Reserve University possessed almost nothing from the Cleveland shale,
he offered me anything of his from that formation "which might be
worth having;" the University gratefully received it all. After his
death, Mrs. Piwonka, at his request offered the remainder of the collec-
tion to the University, "such portion as might be thought worth
having." The whole collection is not large, but contains much material
from the Cleveland and Sandusky regions, all carefully marked as to
locality, all valuable, particularly that from the Cleveland shale which
yields material only on long careful search. Some of the material is
unique. In earlier years, he had been equally generous with his findings,
and the collections of both the United States Geological Survey and of
the Dominion Geological Survey of Canada, have been enriched at his
hands ; in the days when Dr. Clark combed all Cleveland fish-producing
localities twice yearly, an occasional choice specimen was obtain by
him from Mr. Piwonka, which must since have lodged either in the
British Museum or the American Museum of Natural History.

Before his death, he donated to the Department of Geology of
Western Reserve University a generous sum of money to defray
expenses of members of the department in making extensive field trips
or elaborate collections. The donation was unsolicited, and was made
with the firm assertion that he did not do it in any effort to perpetuate
his name (indeed, he rather insisted that his name be left out of it) ;
that though fortune had not been lavish with him, yet she had not
been unkind, perhaps kinder than to most individuals engaged in
University work, and he wished to defray a part of the expense that
they are frequently put to in the prosecution of their interests. This
sum has already been of service, and will be of yet more service, in the
recovery of the last fish and amphibian remains that can possibly be
obtained from the famous old Linton Coal-Measures locality of eastern
Ohio.

Mr. Piwonka was bom in New York City of Bohemian stock. He
was valedictorian of his class from Central High School, Cleveland.
His interest in natural science was first aroused by S. G. Williams, then
a teacher in Central High School (who later became Professor of Edu-
cation in Cornell University, and whose collection forms the bulk of the
paleontological collection of Western Reserv^e University). After

16 E. L. RICE Vol. XXII, No. 1

graduation, Mr. Piwonka acted as secretary to the superintendent of
schools for several years, during which time he found time to prepare
himself for admission to the bar in 1876. His life-work was law, but in
spare moments he was a naturalist with particular interest in geology,
botany and microscopy. His passing removes one more (ver}^ f-ew are
left) of that generation of men interested in the natural history of their
locality, with the collector's keen instinct, to which paleontology is
profoundly indebted. With them is passing a phase of our culture.

J. E. Hyde, Committee.

Report of Committee on Resolutions.

The following resolutions were presented by the Committee
on Resolutions and adopted by the Academy:

(1) The Academy wishes to thank the Local Committee, the
oflficers of Western Reserve University and Case School of Applied
Science for their efforts in making the Thirty-first Annual Meeting
of the Ohio Academy of Science a success.

(2) The Academy wishes to express its appreciation of the contin-
ued interest and financial support given to the research work of this
Academy by Mr. Emerson McMillin.

(3) The Academy wishes to express to Professor Charles A. Kofoid,
of the University of California, its thanks for the special lecture on
"Hookworm and Human Efficiency."

(4) The Academy wishes to thank again Professor E. L. Rice for
his efficient services as Secretary of this Academy.

C. G. Shatzer.
Raymond C. Osburn.
Walter H. Bucher.

Amendment of Constitution.

Art. V, Section 3. Election of Fellows. Amended to read:
Fellows shall be elected by joint action of the Executive Com-
mittee and the Vice-Presidents, from nominations endorsed by
two fellows of the Academy. Such nominations shall be accom-
panied by documentary evidence of the candidate's scientific
achievements upon which the nomination is based. Approval
by three-fourths of this joint committee shall be necessary to
election.

Amend^neitt of By-Lwas.

Chap. Ill, Section 5. Nomination of Fellows. New section,
to read: A suitable blank for nomination of fellows shall be
supplied by the Secretary and shall be mailed to each member
of the Academy at least once each year.

Nov., 1921 ANNUAL MEETING — OHIO ACADEMY OF SCIENCE 17

Chap. IV, Section 2. Nominations. Amended to read:
The Academy shall elect by ballot a Nominating Committee,
consisting of one representative from each regularly organized
Section of the Academy, who shall nominate a candidate for
each office, including elective members of the Executive Com-
mittee, the Publication Committee, and the Trusteees of the
Research Fund. Additional nominations may be made by any
member of the Academy.

Proposed Amendment of Constitution .

The following amended form of Art. VI, Section 1, was pro-
posed by the Executive Committee for action at the next
annual meeting: Annual Meeting. The date and place of the
Annual Meeting shall be fixed by Executive Committee, sub-
ject to such instructions as shall be determined by the Academy
at the preceding annual meeting, and shall be announced by
circular at least thirty days before the meeting. The details of
the daily sessions of each meeting shall be arranged by the
Program Committee and announced in the official program
immediately before the meeting.

The Committee on Legislation was also instructed to make
such revision of the Constitution and By-Laws as may be
necessitated in case the Legislature shall pass the proposed bill
providing for State support of the Academy, this instruction
to be interpreted as notice of proposed amendment, enabling
definitive action at the next annual meeting.

Certificate of Election to Fellowship.

The Secretary was instructed to prepare a suitable certifi-
cate to be presented to each newly elected fellow in the
Academy.

Appeal from University of Debreczen.

An appeal from the Director of the Geographical Institute
of the Royal University of Debreczen (Hungary), under date of
December 7, 1920, for "books, used clothes, and even little
sums of money" for the desperately needy students of the
department, was read by the Secretary. No action was taken
by the Academy beyond thus calling the matter to the attention
of the individual members.

18 E. L. RICE Vol. XXII, No. 1

Scientific Sessions.
The complete scientific program of the meeting follows:

PRESIDENTIAL ADDRESS.
Thunderstorms; especially those of Ohio W. H. Alexander

PUBLIC LECTURES.

Hookworm and human efficiency Charles A. Kofoid

Scientific work at the Ohio Bureau of Juvenile Research. . . .Henry H. Goddard

PAPERS.

1. The new Cleveland Museum of Natural History. (15 min.) . . . . Paul M. Rea

2. The state park situation in Ohio. (15 min.) J. Ernest Carman

3. Chronological view of men of science. (7 min.) J- A. Culler

4. A peculiar case of stature inheritance. (3 min.) A. B. Plowman

5. A differential sensitivity theory of time and space and its bearing on

evolution. (7 min.) L. B. Walton

6. The relation of the biologist to public health administration. (15 min.),

A. B. Plowman

7. The function of the striae and the origin of bilateral symmetry in the

euglenoids. (15 min.) (Lantern) L. B. Walton

8. The geographical distribution of the genera of Opalinidae. (20 min.),

(Opaque projection) Maynard M. Metcalf

9. Hemiptera of the Adirondacks. (10 min.) (Lantern) Herbert Osborn

10. Collecting in southern Florida. (10 min.) Herbert Osborn

11. Some studies in Hessian fly emergence. (10 min.) (Lantern). .T. H. Parks

12. Notes on the habits and life history of Galeatus peckhami Ashm.

(5 min.) (Lantern) Carl J. Drake

13. A new Ambrosia beetle: notes on the work of Xyloterinus politus Say.

(6 min.) (Lantern) Carl J. Drake

14. Phylogeny and distribution of the genus Libellula. (20 min.) (Lantern),

Clarence H. Kennedy

15. Aids in teaching elementary cytology. (By title) Z. P. Metcalf

16. The cytology of the sea-side earwig Anisolabis. (15 min.) . . S. I. Kornhauser

17. Copulation in Planaria maculata. (5 min.) R. A. Budington

18. On the regulative capacity of the neural tube. (15 min.) (Lantern),

H. L. Wieman

19. The musculature of the head and throat of the Chimaera ogilvyi. (15 min.)

(Lantern) Mae Freidlander

20. New models of the development of the heart in the chick. (20 min.),

Bradley M. Patten

21. Some features of the morphology of the kidney of Nee turns. (20 min.),

S. W. Chase

22. Orientation in the cat. (5 min.) Francis H. Herrick

23. Diet of a captive mole. (5 min.) E. L. Moseley

24. Additions to the birds of Ohio. (10 min.) Lynda Jones

25. Phagocytoses and clotting in the perivisceral fluid of Arbacia. (10 min.),

J. E. Kindred

Nov., 1921 ANNUAL MEETING — OHIO ACADEMY OF SCIENCE 19

26. Further observations as to effect of thyroid substance on plant pro-

toplasm. (5 min.) R. A. Budington

27. The origin and development of the prairie in North America. (40 min.),

(Lantern) H. C. Sampson

28. The significance of native vegetation in crop production. (35 min.),

(Lantern) A. E. W.\ller

29. Energy relations of an acre of corn. (5 min.) E. N. Transeau

30. Some energy relations of aquatic life and their significance. (10 min.),

L. H. Tiffany

31. Contributions to the genetics and cytology of parthenogenetic Taraxaca.

(5 min.) Paul B. Sears

32. Reversal of the sexual state in the Japanese hop. (10 min.) . .J. H. Schaffner

33. The occurrence and abundance of certain algae in Lake Erie. (10 min.),

Malcolm E. Stickney

34. The census of flowering plants on certain small islands of Lake Erie.

(8 min. ) Malcolm E. Stickney

35. Causes and consequences of the irregularities in the glacial border in

the Ohio Valley. (30 min. (Lantern) G. Frederick Wright

36. Explorations in Eastern Bolivia. (20 min.) K. F. Mather

37. Some sub-surface rock channels filled with glacial material. (15 min.),

J. Ernest Carman

38. A fault-zone breccia in the Bass Island series. (10 min.) . .J. Ernest Carman

39. A disconformable contact at the base of the Sylvania sandstone. (5 min.)

J. Ernest Carman

40. The Ordovician and Silurial seas of American Arctic and Subarctic

regions and the relation of their faunas to contemporaneous seas of
European areas. (20 min.) Aug. F. Foerste

41. Some coastal geology of southern Florida. (20 min.) G. F. Lamb

42. An interpretation of some Ohio geology. (12 min.) G. F. Lamb

43. Richmond Ostracoda of especial interest. (10 min.) W. H. Shideler

44. Additions to our knowledge of the Amheim. (10 min.) . . . . W. H. Shideler

45. A Pliocene brackish water fauna near Alexander, La. (10 min.). .E. R. Smith

46. A modification of Hobbs's method of teaching interpretation of geologic

maps. (10 min.) E. R. Smith

47. An embryonic volcano in Adams County, Ohio. (15 min.),

Walter H. Bucher

48. Local geology of Cleveland from an economic standpoint. (25 min.),

(Lantern) Frank R. Van Horn

49. The reopening and the end of the Linton (Ohio) Coal-measures, fossil-

amphibian locality. (10 min.) J. E. Hyde

50. The fauna of the Berea Grit; a recurrent Bedford faima, and its bearing

on the age of the Bedford. (15 min.) J. E. Hyde

51. Some psychology applied to Americanization. (20 min.). .Garry C. Myers

52. Scientific direction of childhood — America's greatest social and political

responsibility. (30 min.) Herman H. Young

53. Reliability of survey methods in individual diagnosis. (20 min.),

Florence Fitzgerald

54. Limiting factors in human behavior. (5 min.) A. P. Wise

55. Waste of mental ability in our school system. (10 min.) . . . Helen Marshall

56. (a) Some studies in progress in the Cleveland School of Education.

(b) Some data on learning curves. (30 min.) Garry C. Myers

57. College men in the penitentiary. (20 min.) Carl Murchison

20 E. L. RICE Vol. XXII, No. 1

58. A preliminary report on retroactive inhibition (with particular reference

to two conditions). (20 min.) E. B. Skaggs

59. The measurement of psychological effects of fatigue and low oxygen.

(20 min. (Lantern) C. F. Dockeray

60. Discussion of the legal status of psychology in Ohio State.

Discussion led by H. Austin Aikins

DEMONSTRATIONS.

(a) Chromosomal complexes of Anisolabis S. I. Kornhauser

(b) Geographic distribution maps for the Opalinidae and their hosts,

Maynard M. Metcalf

(c) New models of development of the heart in the chick Bradley M. Patten

(d) Chart and data relating to an interesting case of stature inheritance,

A. B. Plowman

(e) Multiple ova in Graafian follicles of cat Edward L. Rice

(f) Sulphur dioxide injury to vegetation A. E. Waller

(g) Illustrations of euglenoids L. B. Walton

THUNDERSTORMS: ESPECIALLY THOSE OF OHIO.*

WILLIAM H. ALEXANDER
Meteorologist, U. S. Weather Bureau, Columbus, Ohio

I. Thunderstorms in General.

1. Introduction

The typical thunderstorm, that is, the thunderstorm com-
plete in every detail from its beginning to its ending, has ever
held a unique place in the world of human thought and spec-
ulation as evidenced by its large and conspicuous place in
ancient mythology, by its scarcely less conspicuous place in
the histor}^ and literature of the race, and by the earnest
consideration it has received from the brightest minds of the
scientific age. Not only so, but its physical characteristics
are such as to assure it a place of real and permanent interest
in our present and future thinking along meteorological lines.

We are told upon apparently good authority^f that more
myths have gathered about the thunderstorm and its phe-
nomena than about any other natural phenomenon, except
possibly light and darkness. And we are quite prepared to
believe it when we recall the ominous stillness of the air, the
darkness of the sky, the lurid glare of the clouds, the majestic
roar of the thunder, and the indescribable effects of the highly
electrified bodies on the nerves of many people. If these storms
inspire so much awe in the human mind in a scientific age — in
these days of our boasted intellectual emancipation — with
what unspeakable awe must the primitive mind have regarded
them! No wonder the thunderstorm was looked upon as a
mystery that pressed for solution or explanation. These early
^'explanations" have come down to us as myths, which, like
most myths, are of interest to us chiefly because they consti-
tute the first efforts of the human mind to explain natural
phenomena. Then, as now, a thing was regarded as explained
when classified with other things with which we are acquainted.

*Presidential address, delivered at the Cleveland meeting of the Ohio
Academy of Science.

fFor numbers of reference, consult bibliography at close of paper.

21

22 WILLIAM H. ALEXANDER Vol. XXII, No. 1

We explain, for example, the origin, the progress and the
ending of a thunderstorm when we classify the phenomena
presented by it with other more familiar phenomena of vapor-
ization and condensation. But primitive man explained the
same thing, to his own satisfaction at least, when he classified
it along with the well-known phenomena of human volition by
constructing a theory of a great black dragon pierced by the
unerring arrows of an heavenly archer. As late as 1600, a
German writer would illustrate a thunderstorm destroying a
crop of corn by the picture of a dragon devouring the produce
of the field with his flaming tongue and iron teeth. But we
of today no longer regard the thunderstorm as an object of
terror or as an unfathomable mystery, but rather as a natural
phenomenon of great economic and scientific interest, one in
every way worthy of our best and most serious consideration.

The physics and physical features of the thunderstorm are,
we believe, fairly well understood. These have been ably and
fully discussed by Professor Humphreys of the U. S. Weather
Bureau, whose teaching we follow very closely in this discussion.
If the thunderstorm produced only lightning and thunder, it
would be of only relative importance, but it may bring along
a whole series of redoubtable phenomena, thus presenting
problems of real practical importance — problems the magni-
tude and importance of which are not always fully appreciated.

2. Definition

And now, first of all, let us ask and answ^er, if we can, this
question: ''What is a thunderstorm?" Ordinarily, for example,
we think of a w^indstorm as a storm characterized by high and
perhaps destructive winds; of a hailstorm as one characterized
by the production of hail; of a snowstorm as one that produces
snow; of a dust storm as one characterized by a great quantity
of flying dust; and so, quite properly, we think of a thunder-
storm as a storm characterized by thmider and lightning. This
may not, I grant you, serve as a satisfactory definition, but it
will, perhaps, be a sufficient answer for the time being to the
question asked.

It is not necessary in this presence, perhaps, to point out
that the "snow," the "wind," the "hail," and the "dust,"
are in no sense the cause of the storm to which they give name.

Nov., 1921 THUNDERSTORMS 23

Nor, so far as known, have the lightning and thunder any
influence on the formation, progress and termination of the
thunder-storm, although they may and often do constitute
the most impressive, spectacular, and even tragic features of
the storm. For as Prof. Humphreys well says,^ "No matter
how impressive or how terrifying these phenomena may be,
they never are anything more than mere incidents to or products
of the peculiar storms they accompany. In short, they are
never in any sense either storm-originating or storm-controlling
factors."

3. Source of the Lightning

Since w^e cannot have a thunderstorm without thunder,
and cannot have thunder without lightning, it seems quite
essential to a proper understanding of these storms to get a
correct, scientific explanation of the source or cause of the
lightning. Oh, yes, we are fully aware of the danger just here —
namely, how easily and how quickly one may get beyond his
depth when talking about the origin of electricity. We must
admit, of course, that we know very little if anything for
certain at this point, but then we would like to appear to know
something about this interesting phase of our discussion. We
are deeply indebted to Dr. G. C. Simpson^ of the Indian
Meteorological Department for our best information or knowl-
edge on this point. Dr. Simpson, by numerous observations and
laboratory experim.ents found out a great many extremely
valuable things concerning the electricity brought down by the
raindrop and the snowflake, and at the same time, by means
of a number of well-devised experiments, determined the
electrical effects of each obvious process that takes place in
the thunderstorm. He found out, for example, that no elec-
trification resulted from freezing and thawing, air-friction, etc.,
but that when he allowed drops of distilled water to fall through
a vertical blast of air of sufficient strength to produce some
spray,

(1) That breaking of drops of water is accompanied b}^ the

production of both positive and negative ions.

(2) That three times as many negative ions as positive ions

are released.

"Now," as pointed out by Professor Humphreys-, "a
strong upward current of air is one of the most conspicuous

24 WILLIAM H. ALEXANDER Vol. XXII, No. 1

features of the thunderstorm. It is always evident in the
turbulent cauliflower heads of the cumulus cloud, the parent,
presumably, of all thunderstorm. Besides, its inference is
compelled by the occurrence of hail, a frequent thunderstorm
phenomenon, whose formation requires the carrying of rain-
drops and the growing hailstones repeatedly to cold and there-
fore high altitudes. And from the existence of hail it is further
inferred that an updraft of at least eight meters per second
must often occur within the body of the storm, since, as exper-
iment shows, it requires approximately this velocity to support
the larger drops, and even a greater velocity to support the
average hailstone.

"Experiment also shows that rain can not fall through air
of ordinary density w^hose upward velocity is greater than
about eight meters per second, or itself fall with greater
velocity through still air; that in such a current, or wdth such
a velocity, drops large enough, if kept in tact, to force their
way dowm, or, through the action of gravity, to attain a greater
velocity than eight meters per second with reference to the
air, w^hether still or in motion, are so blown to pieces that the
increased ratio of supporting area to total mass causes the
resulting spray to be carried aloft or left behind, together
with, of course, all original smaller drops. Clearly, then, the
updraft s within a cumulus cloud frequently must break up at
about the same level innumerable drops which, through
coalescence, have grown beyond the critical size, and thereby
according to Simpson's experiments, produce electrical sep-
aration within the cloud itself. Obviously, under the turmoil
of a thunderstorm, its choppy surges and pulses, such drops
may be forced through the cycle of union (facilitated by any
charges they may carry) and division, of coalescence and dis-
ruption, from one to many times, with the formation on each
at every disruption, again according to experiment, of a corre-
spondingly increased electrical charge. The turmoil compels
mechanical contact between the drops, whereupon the charges
break down the surface tension and insure coalescence. Hence,
once started, the electricity of a thunderstorm rapidly grows to
a considerable maximum.

"After a time the larger drops reach, here and there, places
below which the up-draft is small — the air can not be rushing
up everywhere — and then fall as positively charged rain,

Nov., 1921 THUNDERSTORMS 25

because of the processes just explained. The negative electrons
in the meantime are carried up into the higher portions of the
cumulus, where they unite with the cloud particles and thereby
facilitate their coalescence into negatively charged drops.
Hence, the heavy rain of a thunderstorm should be positively
charged, as it almost always is, and the gentler portions neg-
atively charged which very frequently is the case.

"Such in brief, is Dr. Simpson's theory of the origin of the
electricity in thunderstorms, a theory that fully accounts for
the facts of observation and in turn is itself abundantly sup-
ported by laboratory tests and simulative experiments.

" If this theory is correct, and it seems well founded, it must
follow that the 07ie essential to the formation of the giant
cumukis cloud, namely, the rapid uprush of moist air, is also
the one essential to the generation of the electricity of thunder-
storms. Hence the reason why lightning seldom if ever occurs
except in connection with a cumulus cloud is understandable
and obvious. It is simply because the only process that can
produce the one is also the process that is necessary and suf-
ficient for the production of the other."

4. Turbulence of the Cumulus Cloud.

That the large cumulus clouds, especially those that pro-
duce thunderstorms, are exceedingly turbulent within with
violent vertical motion, as demanded by the theory just out-
lined, is evident to even the casual observer. Furthermore the
testimony of those balloonists who have had the trying ordeal
of passing through the heart of a thunderstorm confirms the
facts of observation. Since these are the only clouds, appar-
ently, characterized by this high degree of turbulence, it may
be well to pause a moment and ask why these motions — niotions
which, in the magnitude of their vertical components and
degree of turmoil, are never exhibited by clouds of any other
kind nor are they met with elsewhere by either manned, sound-
ing or pilot balloons. Without going into very great detail, it
may be pointed out, as has been done by von Bezold'*, that
the heat liberated by the sudden condensation from a state of
supersaturation, and also from the sudden congelation of
undercooled cloud particles, would cause an equally sudden
expansion of the atmosphere, resulting in turbulent motions
analogous to those observed in the large cumulus clouds.

26 WILLIAM H. ALEXANDER Vol. XXII, No. 1

This, however, is not sufficient to account for all the observed
facts, since it is not clear just how either the condensation or
the congelation could suddenly take place throughout a cloud
volume great enough to produce the observed effects. We
must, therefore, look for some other explanation, and this we
shall probably find, in the difference between the actual tem-
perature gradient of the surroimding atmosphere and the adiahatic
temperature gradient of the saturated air within the cloud itself;
or, in other words, the cause of the violent up-rush and tur-
bulent condition within large cumulus clouds is, presumably,
the difference between the temperature of the inner or warmer
portions of the cloud itself and that of the surrounding atmos-
phere at the same level.

5. Causes of Convectional Instability.

As we have just tried to show the sine qui non of the thun-
derstorm is the rapid vertical convection of moist air; the up-rush
must be rapid and the air must be moist; one without the
other is not sufficient. We may have, for example, a very rapid
convection over a desert region but there being no moisture
there will be no cloud-formation and therefore no thunderstorm.
On the other hand we may have air ever so humid but if the
movement upward is too gentle not even a cloud may result,
but if a cloud, certainly no thunderstorm. It is obvious,
therefore, that we must have both "rapid convection" and
"moist air."

This leads us to a consideration of the conditions under
which the vertical temperature gradients necessary to this
convection can be established. These conditions are, according
to Prof. Humphreys, three in number, namely:

(1) A strong surface heating, expecially in regions of light

winds.

(2) The over-running of one layer of air by another at a

temperature sufficiently lower to induce convection.

(3) The under-running and consequent uplift of a saturated

layer of air by a denser layer.

Of these three conditions, the first mentioned — "strong
heating surfaces" — is, for obvious reasons, of most frequent
occurrence over the land surfaces of the earth; number two is
also of frequent occurrence on land and is, perhaps, well nigh the

Nov., 1921 THUNDERSTORMS 27

sole cause of thunderstorms on the ocean. Number three is
by far less frequently the cause of thunderstorms than the
other two, for while the actual under-rtinning is of rather fre-
quent occurrence, it seems probable that only occasionally is
the uplift of sufficient magnitude to cause a thunderstorm.

6. Periodic Recurrence of Thunderstorms.

Keeping in mind the conditions or factors absolutely essen-
tial to the formation of a thunderstorm, we are well prepared
to consider, perhaps in a measure to anticipate, the periodic
recurrence and distribution of thunderstorms, for while it is
possible, of course, for a thunderstorm to occur on any day at
any hour, yet the fact is, and for obvious reasons, the day has
its period of maximum thunderstorm activity, the year its max-
imum period, and there is some evidence of irregular cyclic
periods of maximum activity, each maximum depending upon
the simple facts that the more humid the air and the more
rapid the local vertical convections the more frequent and also
the more intense the thunderstorms.

Taking the day as our unit, we find the period of maximum
thunderstorm activity is not the same over the land as over
the ocean. Vertical convection of the atmosphere over the
land is most pronounced, of course, when the surfaces are most
heated, namely, in the afternoons; hence the inland or con-
tinental thunderstorm occurs most frequently, in most places,
between 2 and 4 P. M. Over the ocean, however, the temper
ature gradients that are most favorable for rapid vertical
convection are most frequent during the early morning hours,
and therefore thunderstorms usually occur on the ocean between
midnight and 4 A. M. If we take the year as our unit, w^e find,
for reasons that will readily occur to all, that thunderstorms
are most frequent, over the land, when the surface heating is
at a maximum, in middle latitudes in June and in the higher
latitudes in July or August. Over the ocean, however, the
thunderstorm is most frequent in the winter months.

Furthermore, since the thunderstorm is vitally associated
with rainfall and high temperature, it must follow that a cycle
of warm, wet years would give a maximum of thunderstorms
and a cycle of cold, dry years a minimum.

We have the key to the geographical distribution of thun-
derstorms in the conditions essential to their production, and

28 WILLIAM H. ALEXANDER Vol. XXII, No. 1

while it is safe to sa}^ that the thunderstorm, in one form or
another, does occur at some time or other in all parts of the
earth, yet from what we know of the meteorological conditions
ordinarily prevailing over the various portions of the earth, we
are very sure that it is very rare over large areas and may
never occur in some regions. In the United States^ for exam-
ple, we find two centers of maximum thunderstorm activity, one
over Tampa, Florida, and the other over Santa Fe, New Mexico.
In the ten-year period, 1904-1913, 944 thunderstorms were
recorded at Tampa and 710 at Santa Fe. Tampa is near sea-
level and Santa Fe is about 7,000 feet above the sea.

7. Classification of Thunderstorms.

One is impressed with the very great variety and many
variations met with in the study of these storms. This is true
whether one is considering the attendant circumstances, the
varying degree of intensity exhibited by them, the frequency of
occurrence, the resulting effects, the distribution through the
day, the year, or over the earth's surface, or whether one is
considering the factors operating to produce and maintain
these storms. Variety everywhere!

At one time, and not so long ago, it was thought that all
thunderstorms were local phenomena and were therefore not
subject to any general law. In an important sense the thunder-
storm is a local phenomenon but the forces operating to pro-
duce many of them are far from local. It is now known that
a majority of these storms travel in a definite direction and
are therefore moving under a general law. In general, with
respect to the producing causes or conditions out of which
they grow, thunderstorms may be divided into (1) local or
"heat" thunderstorms, and (2) the cyclonic thunderstorms, or
"thundersqualls." Or, if we wish to be a little more exact or
"scientific," w^e may follow Professor Humphreys and make
five classes, namely, (1) the "heat" or local, (2) the cyclonic,
(3) the tornadic, (4) the anti-cylconic, and (5) the "border,"
thunderstorm. The significance of this classification will be
pointed out later in connection with the illustrated portion of
this lecture but it seems appropriate at this time to refer to
Durand-Greville's famous theory of "the squall zone" in con-
nection w4th cyclonic thunderstorms. He holds that "cyclonic
thunderstorms" — and that means all except the "local" or

Nov., V.)2\

THUNDERSTORMS

29

"heat" thunderstorm — are but an accessory result of a body
of extremely complex phenomena — an organism someone has
called it'' — the squall, which is subject to fixed laws and forms
an integral part of certain lows. This so-called "squall zone"
in which, according to Durand-Greville^, nearly all "cyclonic"
thunderstorms, or as he calls them, "thundersqualls," occur,
starts some where near the center of the barometric depression
■or "low" and usually extends out to its boundary, thus having
a length of a thousand miles or more, while its width may vary
from 10 to 60 miles or more. This zone moves, advances or
recedes, with the "low" of which it is a part, as a rule remain-
ing parallel with itself. Should the "low" remain stationary,
the squall zone may, and usually does, swing round the center.
The passage of the "squall zone" over any given place, shown
by the familiar "squall hook" of the barograph trace, is
attended by the concomitant production of certain phenomena
that occur only within the limits of the zone. They begin at
the moment the "squall front" of the squall zone reaches the
place of observation, they rapidly attain their maximum, inten-
sity, and then gradually weaken and finally die out as the rear
of the zone passes and normal conditions become established.
These accompanying phenomena may be more or less numerous,
thus giving rise to a variety of "squalls," each characterized
by its appropriate phenomena. These squalls have been clas-
sified by Durand-Greville as follows, viz.:

Durand-Greville's Classification of Squalls*

2.

3.

Sudden increase in
wind velocit3^ . .

Sudden change in
wind direction. .

Sudden rise in
pressure

Sudden fall in

Whitel
' squall

•6.

7.

S.

pressure

Sudden rise in

relative humidity.
Rapid increase in

cloudiness

Downpours of

rain

hail

_ Wind
squall

snow

Lisfhtning: and thunder.

Rain,
hail,
or
snow squall

Thunder
squall

30 WILLIAM H. ALEXANDER Vol. XXII, No. 1

The basis of this classification is, as you see, increasing
complexity. Note also that the phenomena observed during
the passage of a squall are actually the results of two causes,
one of these, the "squall wind," is purely dynamic, pre-existant,
and may be of distant origin; the other is the local condition of
the atmosphere and is static.

8. The Mechanism of the Thunderstorm.

Thus far we have considered the thunderstorm in a more
or less general way — its definition, its causes, its recurrence, its
distribution, its relation to areas of high and low pressure, etc.
Let us now consider a typical thunderstorm in actual progress
and note its mechanism and some of its more important phe-
nomena. Just here the slide would be very helpful but we shall
content ourselves just now with the bare mention of some of
the things that one may look for in the well-defined thunder-
storm. Among these may be mentioned the winds, the squall
cloud, the pressure, the temperature, the humidity, the rain,
the hail, the so-called "rain-gush/' the rate of advance of the
storm, the lightning, and the thunder.

First, the thunderstorm winds must be carefully considered
if one is to understand fully the mechanism of the thunderstorm
itself. As every one knows, as a thunderstorm approaches a
given place the wind at that place is generally light and from
a direction that carries it across the path of the approaching
storm, that just before the rain begins the wind begins to die
down, almost to a calm, and to change its direction. When
this change is complete it blows for a few moments, rather
gently, directly toward the nearest portion of the storm front,
and finally as the rain is almost at hand, there is a sudden
change of direction and the wind now comes, often in violent
gusts, directly away from the storm and in the direction the
storm is moving, a direction quite different from the original
direction of the wind. As a rule these strong gusts of wind last
through the early part of the storm only and then follow gentle
winds again, at first following the storm but after an hour or
so they blow from the same general direction as the original
surface winds. Now, as we have tried to show, the thunder-
storm is the child of a cumulus cloud and the cumulus cloud
is the child of a vertical convection which results from a more
or less super-adiabatic temperature gradient. This gradient

Nov., 1921 THUNDERSTORMS 31

may be established in one of three ways, as above pointed out.
Now, inasmuch as the passage of a cumulus cloud overhead,
however large, so long as rain does not fall from it, does not
materially disturb the surface winds, in other words, does not
bring on any of the familiar gusts and other thunderstorm
phenomena, we must infer that in some way the rain is an
important factor both in starting and maintaining the winds
we have just noted. On the other hand we cannot assume
that the rain is the whole cause of these winds for they do not
accompany other and ordinary showers, however heavy the
rainfall.

The "rain-gush" or heavy downpour after a heavy clap
of thunder has often been misunderstood and has been made
to serve as a proof of the claims of the so-called "rain-makers."
The fact is the rain is the cause of the thunder or lightning,
and not the thunder the cause of the heavy rain.

Then there is the lightning in its various forms, the "streak"
lightning, the so-called "rocker" lightning, the "ball" light-
ning, the "sheet" lightning, the "beaded" (?) lightning, the
"return" lightning, and some people say the "dark" lightning,
and so on. To discuss all these would carry us far beyond our
limit. Then there is the question of the temperature along the
path of a lightning discharge, how does the lightning render the
atmosphere through which it passes luminous, etc. Perhaps no
one knows the answer to these questions but it is very certain
that the temperature along the path of the lightning discharge
is very high from the fact that it sets fire to many objects, such
as buildings, that fall within its path. Just how the lightning
discharge renders its path through the atmosphere luminous is
not definitely known. Of course it does make the air along its
path very hot but no one so far as I know has ever succeeded
by any ordinary means in rendering oxygen or nitrogen luminous
by heating. It must be therefore, that the luminosity?- is due to
something besides high temperature, probably, according to
Prof. Humphreys, to "internal atomic disturbances induced by
the swiftly moving electrons of the discharge." The spectrum
reveals to us the interesting fact that lightning flashes are of
two colors, white and pink or rose. The rose-colored flashes,
when examined in the spectroscope, show several lines due to
hydrogen, which of course are due to the decomposition of
some of the water along the lightning path. The duration of

32 WILLIAM H. ALEXANDER Vol. XXII, No. 1

the lightning discharge is exceedingly variable, ranging from
0.0002 second for a single flash to, in rare cases, even a full
second or more for a m.ultiple flash consisting of a primary and
a series of subsequent flashes. The lightning discharge is
direct, not alternating, as shown by the fact that the lightning
may operate telegraph instruments, may reverse the polarity of
dynamos, both of which requires a direct current.

The length of the lightning streak also varies greatly.
When the discharge is from cloud to earth the length is seldom
more than 2 or 3 kilometers, but when from cloud to cloud
may be 10 to 20 kilometers (6 to 12 miles). The path of the
lightning discharge may extend from the cloud to earth, from
one portion to another of the same cloud, or from one cloud to
another cloud. Obviously the second case is of the most fre-
quent occurrence, that is, from the upper to the lower portion
of the same cloud; from cloud to earth is next in point of fre-
quency, and from cloud to cloud, relatively rare. Sometimes
the discharge from cloud to earth may include in its strange
and tortuous path objects that have not sufficient conductivity
to carry it and as a result of the sudden and excessive heating
many very freakish things may be done, such as shingles blown
off, chimneys shattered, trees stripped of their bark or splin-
tered, wdres fused, even holes melted through metal, etc. Then
there are certain chemical reactions resulting from these elec-
trical discharges that play an important part in the economy of
nature. For instance the health-giving ozone of the atmosphere
is greatly increased by the passage of a thunderstorm, and even
the fertility of the soil may be increased by the production of
considerable quantities of ammonia and soluble salts.

Perhaps, a w^ord or two should be said regarding the danger
to life incident to the passage of a thunderstorm. That there
is danger, even great danger at times, is abundantly shown
from the tragic statistics of deaths each year from this cause.
While it is not possible, perhaps, to remove this danger, it is
possible to reduce it, chiefly by avoiding the points of greatest
danger. In general, it is safer inside than outside of a house,
especially if the house has a well-grounded rod or metal roof;
it is also safer in the valley than on a hill or elevated portion
of land, this because the chance for a cloud-to-earth discharge
varies inversely as the distance between them; it is also very
unsafe to take refuge under a tree and the taller the tree the

Nov., li)21 THUNDERSTORMS 33

greater the danger. No tree is immune but those trees having
an extensive root system or a deep tap-root are most apt to be
struck because they are the best grounded and therefore offer
the least electrical resistance. Then again if one is caught
out of doors and is exposed to a violent thunderstorm it is
best so far as danger from lightning is concerned, to let one's
clothes get soaking wet, because wet clothes are much better
conductors and dry clothes much poorer conductors, than the
human body. It might even be advisable to lie flat on the
wet ground, undignified as this may be. For any given local-
ity, the lower the cloud the greater the danger; hence, when
the humidity is high it is favorable for a dangerous storm, since
the cloud will form at a low level and the rain is apt to be very
abundant. For the same reason a winter storm is likely to be
more dangerous than a summer storm of equal intensity.
And now how do we account for the thunder — that par-
ticular feature that gives name to our storm? It has taken
quite a while to answ^er this question satisfactorily. Many
very silly theories still persist. The electrical discharge, the
"lightning," furnishes the key to the explanation. The sudden
and intense heating of the air along the path of the discharge
causes it to expand suddenly and violently, sending out from
every part of its path a steep compression wave, which, as we
understand it, is the real cause of the thunder. The "rumbling"
that sometimes follows is due, chiefly perhaps, to the inequality
in the distances from the observer to the various portions of the
lightning's path, to the crookedness of the path, to a succession
of discharges, and to some extent to reflection under favorable
conditions. The distance to which thunder may be heard
varies from 7 to 15 miles.

9. Forecasting the Thunderstorm.

The forecasting of conditions favorable for the formation
of thunderstorms one or two days in advance is comparatively
easy but to say, even a few hours in advance, that a thunder-
storm will occur at a given place, at or about a given time, is,
to say the least, a hazardous venture. It is only after the
storm has actually begun and its direction and rate of move-
ment have been determined, can one speak with even a small
degree of assurance. As every one knows, a storm may occur,
in fact several of them, in sight of the observer and yet not at

34 WILLIAM H. ALEXANDER Vol. XXII, No. 1

the place of observation. Then besides the thunderstorm is of
a very limited duration; it may, at the very most, last twenty-
four hours, but as a rule a very few hours will exhaust it. It is
only when this type of storm assumes the character of a tornado
that knowledge of its approach becomes really important.

10. The Thunderstorm aitd Excessive Precipitation.

Another thing that gives to the thunderstorm economic
importance is the fact that from 66 to 100 per cent of all
instances of excessive precipitation in the United States occur
as the result of or in connection with thunderstorms^ Some
places, like Bismark, Denver and Sante Fe, excessive precip-
itation never occurs except in connection with thunderstorms.
Furthermore, the records will show that practically all cases of
remarkable downpours of rain or hail occur in connection with
these storms.

II. Thunderstorms in Ohio.

1. Introduction.

Needless to say, the thunderstorms of Ohio do not differ
in any essential respect from those we have been discussing.
Our chief and perhaps only excuse for referring to them at
this time and in this manner is to make an occasion to call the
attention of the Academy to a piece of work accomplished in
Ohio that, so far as we know, is the only one of its kind in this
or any other country, namely an intensive study of thunder-
storms over a limited region through a period of one year. The
purposes were to determine as far as practicable the origin,
the distribution, the number, the frequency, the extent of
territory covered, the attending phenomena, etc., of these
storms, and if possible, trace the history of each individual
thunderstorm that entered or originated in the state of Ohio,
during the year 1917.

2. The Plan.

Our plan was to secure at least one observer in each town-
ship in the State but as the work was to be purely gratuitous
we were not able to interest one person in each of the 1357
townships. Our total enlistment was about 730 volunteer

Nov., 1921 THUNDERSTORMS 35

observers, about 130 co-operative observers and the six regular
Weather Bureau stations in the State. We also received some
assistance from the telephone and telegraph companies in the
State and even dealers in lightning rods.

3. Forms and Instruction.

Each observer was then supplied with full instructions and
a suitable card on which to make his report of each storm.
This form called for the exact date and time of the storm, the
exact location of the observer, time first, loudest and last
thunder was heard, direction the storm moved, time rain
began and ended, time hail began and ended, direction of wind
before and after the storm, etc. The weakness of the plan was,
of course, in the fact that it was dependent upon voluntary
service and as was to have been expected, some observers
failed us at the critical moment, so that we were not always
sure we had the complete history of each storm. However, we
assembled quite a mass of thunderstorm data and these have
been charted and otherwise prepared for publication.

3. A Resume.

Among the many interesting facts brought out in the
special study of thunderstorms in Ohio during the year 1917,
may be mentioned, briefly, the following :

(a) Thunderstorms in Ohio are incident to the passage of
those cyclonic areas (see M. W. R., Supplement No. 1) that
move directly over or just north of the State, and to the
approach of those that move just south of the State. The first
group includes the Alberta, the North Pacific, the Rocky
Mountain and probably the Central and Colorado types; the
second group includes the South Pacific and the Texas types,
especially those that follow a northeasterly course.

The passage of the Alberta type, especially in the late
winter or early spring months, will cause thunderstorms in
Ohio when the wind-shift line, or "squall line," is pronounced,
and extends in a north-south, or a northeast-southwest direc-
tion. These thunderstorms will set in slightly in advance of this
line and will continue until it has passed. See weather map
of January 31, 1917, 7 A. M. The passage of the North Pacific,
the Northern Rocky Mountain, the Central, and the Colorado

36 WILLIAM H. ALEXANDER Vol. XXII, No. I

types, will cause thunderstorms in Ohio only when an area of
high pressure prevails over the eastern Lake Region or New
England. See weather map of April 17, 1917, 7 A. M. As these
types are usually followed by a high pressure area from the
northwest of more or less intensity and therefore move with
considerable rapidity, the thunderstorms incident thereto are
apt to be of short duration and are seldom of a violent
character.

But to the approach of the South Pacific and Texas types is
to be attributed by far the greater portion of the thunderstorms
in Ohio. These types prevail from early May into late October.
As a rule thunderstorms will set in over the western jDart of
the State when the center of the "low" reaches Missouri or
southern Illinois and will probably become general over the
State. These cyclonic types often bring thunderstorms of a
very violent nature. When the "low" passes over the north-
western corner of the State, thus forcing the isotherms far
northward of their normal position, and is followed by a "high "
of moderate intensity, hailstorms are likely to occur with the
shift of the wind — passage of the squall line — and subsequent
increase in pressure. See weather maps of March 10 and 11,
1917. The position of the Atlantic high does not seem to have
any material effect on the rain -producing characteristics of these
"lows." When the path of these cyclonic types suddenly
curves to the north and passes into the Lake Region from
northern Indiana or Illinois, thunderstorms are likely to occur
in Ohio both on the approach and the passage of these areas.
Normally, however, their passage just over or just south of
the State is followed by brisk westerly winds, clearing weather
and falling temperature.

The East Gulf and South Atlantic types gave rise to no
thunderstorms in Ohio during the year 1917.

(b) The data seem to show^ certain centers of maximum
activity and storm-frequency. The southwestern part of the
State is certainly the most favorable portion for the develop-
ment of the tornado as all tornadoes of consec|uence in the his-
tory of the Bureau have occurred in that section.

(c) Thunderstorms were reported on 169 days, midnight
to midnight. Of these 169 days, thunderstorms occurred in the
forenoon only on 22 days, on the afternoon only on 80 days, on

Nov., 1921 THUNDERSTORMS 37

both forenoon and afternoon on 63 days, on 9 days the storm
began in the forenoon and ended in the afternoon, and on 2
occasions the storm began on the afternoon or evening of one
day and ended in the early morning of the following day. Note
that the afternoon thunderstorm is about four times as fre-
quent as the forenoon, that the number of days with thunder-
storms both morning and afternoon is quite large, that the
number of days on which the storm begins in the forenoon
and continues into the afternoon is quite small and the num-
ber beginning in the afternoon or evening and continuing
beyond midnight is smaller still.

The reports further show that at leats 31 persons were
killed during the year by lightning, 70 others more or less
injured; in addition, a large number of animals were killed and
much property destroyed. We have no reliable figures as to
how many times the lightning actually struck but we learn
from the report of the State Fire Marshal that 215 fires were
started during the year as the result of a lightning stroke,
destroying property valued at about $370,000. The 215 objects
damaged or destroyed were classified as follows: 137 barns,
53 dwellings, 4 churches, 4 sheds, 4 warehouses, 2 haystacks,
2 oil tanks, 1 dry cleaning establishment, 1 hotel, 1 livery
stable, 1 school house, 1 straw stack, 1 manufacturing estab-
Hshment and 2 mercantile buildings. The Fire Marshal's office
takes no note of lightning strokes that do not start a fire or cause
the loss of human life. These fires were distributed through the
months as follows, viz.: February, 5; March, 6; April, 5;
May, 33; June, 27; July, 45; August, 66; September, 17;
October, 11; January, November and December, none.

Another item of considerable interest, perhaps, is that
about 95 per cent of the objects struck were wet at the time
and rain was falling, leaving only about 5 per cent that were
dry and struck when no rain was falling. In one case, the
burning of a bam near Conneaut, Ashtabula County, March
26th, the report seems to indicate that snow was falling at the
time of the stroke that caused the fire.

Another thing: The days on which thunderstorms are
general over the State are relatively few. Of the 169 thunder-
storm days in 1917, on 7 days only were thunderstorms general;
on 11 days they covered about three-fourths of the State; on

38 WILLIAM H. ALEXANDER Vol. XXII, No. 1

23 days about one-half; on 17 days, nearly half the State; on
the rest, they were local and limited.

As intimated above, the publication of this report (Thunder-
storms in Ohio in 1917) has been and is being delayed on
account of lack of the necessary funds.

LITERATURE CITED

1. Jones, George S.

1873. "Myths of the Thimderstorm." The Penn Monthly, October; pp.
680-698.

2. Humphreys, W. J.

1914. "The Thunderstorm and Its Phenomena." Monthly Weather Review,
June; 42: 348-380.

3. 1910. "Memoirs"; Indian Met'l Dept.; Simla, 20, pt. 8.

4. 1892. Sitzber., K. preuss. Akad. d. Wiss., Berlin, 8: 279-309.

5. Alexander, Wm. H.

1915. "Distribution of Thunderstorms in the United States." Monthly

Weather Review, July; 43: 322-340.

6. LOISEL, J.

1909. "Squalls and Thunderstorms." La Nature; 37: 105-108.

7. Durand-Greville, E.

1894. "Les grains et les orages." Bur. cent. met. de France; and Comptes
rendus, 9 avril, 1894.

8. Monthly Weather Review, June, page 238. 1909.

9. Alexander, Wm. H.

"Thiinderstorms. " Pro. 2d Pan Am. Sci. Cong., Sec. II, pp. 55-73. (Esp.
p. 62).

The Ohio Journal of Science

Vol. XXII December, 1921 No. 2

FOOD OF THE COMMON OHIO DARTERS

CLARENCE L. TURNER
Zoological Laboratory, Beloit College

INTRODUCTION.

This paper constitutes one unit of a report of a fish survey
of Ohio undertaken by the Ohio Bureau of Fish and Game
and directed by Professor R. C. Osburn, of Ohio State Univer-
sity. It was the main purpose of this survey to determine the
status of the game and food fishes in the various waters of
the state. In the environmental conditions responsible for the
production of game fishes the food plays an important role and
in order to have all the factors governing the food conditions it
is necessary to determine also the food and feeding habits of
those animals which are themselves used as food by the game
fishes. During their younger stages perch and darters, as well as
the young of many other kinds of fish, furnish food for the
young, yearling and older basses. A report has already been
made upon the food and feeding habits of the young perch
(Turner, 1920) and this report offers a similar study of the
darters.

A part of the work was done at the Lake Laboratory of
Ohio State University at Put-in-Bay during July of 1919 and
the writer is greatly indebted to Director R. C. Osburn, who
with his keen interest and long experience in fish problems, lent
encouragement and advice. During the summer of 1920
Professor Osburn, L. H. Tiffany, E. L. Wickhff and W. C.
Kraatz of Ohio State University, and the writer made extensive
collections from all the larger lakes and reservoirs of the state
as well as from some of the streams of central Ohio. Several
thousands of darters were collected, comprising eleven different

41

42 CLARENCE L. TURNER Vol. XXII, No. 2

species and ranging in size from ten to one hundred millimeters.
Six hundred and twelve of these covering a wide range in
locality, kind of habitat, date of capture and age of individual
were examined.

METHODS.

All the measurements of length include the distance from
the base of the caudal fin to the tip of the jaw or snout.

Very few specimens were examined in a fresh condition,
nearly all being preserved in strong formalin as soon as taken.

Various kinds of seines were furnished by the Bureau of
Fish and Game and practically all the fish were taken by seining.

In determining the quantity and character of the food the
stomach and intestine were dissected out with the aid of a
binocular microscope, the contents removed and, so far as
possible, identified. A compound microscope was also employed
for the identification of smaller objects, after which quantitative
estimates of the various articles of food were made.

FOOD OF EACH SPECIES.

There is a general similarity in the food of the different
species. The most typical feed almost exclusively in their
younger stages upon entomostraca and minute midge larvae,
later increasing the amount of midge larvae at the expense of
the entomostraca. It is worthy of note that larger specimens
of midge larvae are taken as the fishes increase in size. Still
later the young fishes turn to larger insect larvae and this is
their staple adult food. Forbes shows that the younger fishes
of most families pass through these stages and then become
more specialized as adults, eating fish, molluscs, vegetation
or even one-celled organisms. Several variations from the
generalized food habits occur among the darters and the details
of such variations will be taken up in the discussion of each
group.

Dec, 1921

FOOD OF OHIO DARTERS

43

A. Percina caprodes Rafinesque.

There is no question but that Percina caprodes and P.
caprodes variety zebra appear in the collections but no distinc-
tion has been made here. Specimens were taken from Lake
Erie, mainly at Put-in-Bay, many of the streams and from
most of the inland lakes of the state. It was the most common
and widely distributed of the whole group of darters. The
specimens have been divided into three groups, those from
Lake Erie, those from the streams and those from the inland
lakes, as these seem to offer rather definite units of habitat.

TABLE 1.

Food of Percina caprodes from Lake Erie.

Length in mm.

23

24

25

26

27

28

29

30

32

33

34

36

37

39

40-50

50-60

60-70

70-80

No. examined

1

8

8

10

16

8

4

4

2

1

4

1

2

2

10

24

22

6

Articles of diet:
Copepoda

100.

95.

70

82.5

60.6

53.6

77.5

85.

95.

70.

25

60.

87.

5.

10.7

7.7

4.2.

Cladocera

2.5

6.

10.

6.2

12.8

20.

5.

15.

40. i 5.

27.7

.2

2.2

Ostracoda

+

+

1

Midge larvae

3.2

6.

8.5

8.2

10.

10.

1

75.

46.2

54.1

34.

21.

Amphipods

2.5

6.2

.5

18.3

16.8

40.1

May fly larvae

10.

1.5

6.2

7.55

1.5

50.

8.

20

1.

13.4

34.8

Other insectlarvae

12.5

2.5

4.5

20.

Snails

.7

Isopods

.9

Fish remains

10.

1.2

Fish eggs

.1

Flat worms

1.

.2

.2

.6

Round worms

.25

.2

.2

.5

Annelid worms

4.5

11.2

.6

5.

20.

10.

Nauplius larvae

.25

.25

Plant remains

3.2

1.8

6.3

Sand and silt

i

.5

2.6

44

CLARENCE L. TURNER

Vol. XXII, No. 2

TABLE 2.
Food of Percina caprodes from inland lakes.

Length in mm.

30-35

35-40 ,

40-50

.50-60

80-90

90-100

No. examined

1

4

3

2

4

2

Articles of diet:
Copepoda

30.6

1.

Cladocera

22.5

16.6

1.3

Ostracoda

3.

Midge larvae

60.

29.5

29.3

96.5

26.6

7.5

Amphipods

6.6

20.

May fly larvae

38.

11.75

3.3

1.5

30.6

5.

Beetle larvae

15.

13.3

7.

Caddis fly larvae

6.

50.

Other insect larvae

20.2

Fish remains

11.75

Round worms

2.

4.

Plant remains

9.5

4.3

.5

Bottom debris

1.

7.3

7.

TABLE 3.
Food of Percina caprodes from streams.

Length in mm.

25-30

30-35

35-40

40-50

50-60

60-70

70-80

No. examined

1

2

2

1

2

3

1

Articles of diet:
Copepoda

15.

2.5

1.

2.4

Cladocera

1.5

.5

1.

Midge larvae

66.

90.

100.

52.

47.6

May fly larvae

80.

34.

5.

45.

20.

88.

Caddis fly larvae

.5

11.4

11.

Snails

16.6

Fish eggs

5.

Flat worms

.3

Sand and silt

1.

1.

.7

1.

The record of the Lake Erie specimens shows that there are
three rather well-defined periods in the food habits. The young-
est subsist almost entirely upon entomostraca although minute
amphipods and midge larvae are also taken to a limited extent.
During the second period amphipods, insect larv^ and ento-

Dec, 1921 FOOD of ohio darters 45

mostraca are eaten, with the insect larvas and the amphipods
gradually predominating. In the last stage the diet becomes
very complex with the larger insect larvas and amphipods fur-
nishing the larger proportion of the food while the quantity of
entomostraca becomes negligible. Although the quantity of
entomostraca definitely decreases, a few are eaten even by the
largest fish and an occasional individual is found which has
eaten little else.

The specimens taken from the inland lakes were fewer in
number but were more developed, none being smaller than
30 mm. The food habits of this group closely parallels that of
the Lake Erie group but there is one outstanding, if minor,
difference. Entomostraca do not play nearly so constant a
part in the diet although there is a larger proportion eaten by
the smaller fishes. It is to be noted that the waters of the inland
lakes are much more concentrated in their production of insect
food than those of Lake Erie and it is possible that the Lake
Erie fish are compelled to rely upon Entomostraca in the
absence of insect food.

Some interesting variations in food habits are offered by the
fishes from the streams. 1. The food is less varied in the stream
fish. 2. Entomostraca are eaten constantly but in a very small
proportion while midge and May fly larvse furnish almost the
whole food in many cases. 3. Amphipods are wholly lacking
in the food of the stream fishes. 4. There is a proportionately
large amount of molluscan food taken. 5. Planorbis and Physa
are the principal snails eaten by the specimens from Lake Erie
while Ancylus is the only snail taken by the stream fishes.

Summary of Food Habits in Percina caprodes.

1. Younger specimens subsist mainly upon entomostraca.
2. Insect food and entomostraca are taken by the intermediate
individuals. 3. The larger specimens have a more complicated
diet but entomostraca are continued as a constant though small
item and insect larvas form the principal constituent. 4. Spec-
imens from the inland lakes vary somewhat from the course
followed by the Lake Erie specimens. 5. Fishes from the
streams differ markedly in their food habits from those from
Lake Erie and the inland lakes.

46

CLARENCE L. TURNER

Vol. XXII, No. 2

B. Diplesion blennioides Rafinesque.
This darter is well distributed and great numbers of them
were taken in the streams throughout the state. A few of the
older ones and a fair number of the younger ones were taken in
the vicinity of the Bass Islands of Lake Erie. A few were taken
from the inland lakes. Tables 4 and 5 illustrate the compar-
ative food habits of the Lake Erie and the stream specimens.
The data concerning those from the inland lakes was so scant
as not to warrant a table.

TABLE 4.
Food of Diplesion blennioides from Lake Erie.

Length in mm.

15-20

20

21

22

23

25

28

33

36

55

No. examined

3

2

2

4

2

8

6

2

2

1

Articles of diet:
Copepoda

3.33

Cladocera

13.33

1.

Ostracoda

.5

Midge larvae

80.

100.

100.

70.

90.

85.

71.6

90.

100.

100.

May fly larvae

30.

6.4

Beetle larvae

10.

12.

22.

10.

Filamentous algae

.5

Stones and silt

3.34

1.

TABLE 5.
Food of Diplesion blennioides from streams.

Length in mm.

20-25

25-30

30-35

35-40

40-50

50-60

No. examined

9

11

3

4

8

3

Articles of "diet:
Copepoda

.33

8.17

.5

1.25

Cladocera

.24

1.

Ostracoda

3.75

Midge larvae

85.55

63.27

66.66

97.5

42.35

23.33

May fly larvae

14.09

30.

2.

14.

50.8

Beetle larvae

2.5

Caddis fly larvae

.55

12.25

23.33

Snails

.9

Fish remains

4.68

3.34

1.25

Mites

.09

Annelid worms

11.25

Bottom debris

13.33

8.90

10.4

2.64

Dec, 1921 FOOD of ohio darters 47

Midge larvae and may fly larvae seem to furnish the main
articles of diet for both old and young. The very young show
a tendency to incorporate more of the entomostraca in their
diet and it is possible that specimens smaller than any of these
taken may eat still a larger percentage of entomostraca. In
the latter regard there is a slight resemblance to Percina
caprodes but the change from entomostracan food to insect
food is not nearly so well marked in Diplesion. Although
amphipods were abundant in the localities seined, few appear
in the food of Diplesion. Two specimens only from Buckeye
Lake had eaten more than fifty per cent of Amphipods.

The specimens taken from the streams showed a more
varied diet than those from the lakes but the tendency to favor
midge and may fly larvae is still apparent. Silt and debris
appear in large quantities in the stream specimens but these
may have been taken accidentally while the fish were securing
other food.

Summary of food habits in Diplesion hlennioides.

1. The earliest stage, which is marked by the consumption
of entomostracan food in Percina caprodes, is poorly shown in
D. hlennioides. 2. May fly larvse and midge larvae constitute
the main articles of diet for both smaller and larger specimens.
3. Specimens from streams tend to show a more complicated
diet.

C. Boleosoma nigrum Rafinesque.

Specimens of this active little fish were taken in nearly
every stream and inland lake examined. Tables have been
prepared for those from the streams and for those from the
lakes, but the habits are so uniform that little of difi'erence is
offered in such tables. The younger specimens compare favor-
ably with those of Percina caprodes in their selection of ento-
mostraca and minute midge larva3 for food and in their gradual
relinquishment of this food to take up may fly larvae and larger
midge larvae. May fly larvae and midge larvae are the only
animals eaten by many and these forms are not wholly lacking
in the food of any. The constant occurrence and large quan-
tities of silt and debris indicate a selection of this material by
the fish for food.

■48

CLARENCE L. TURNER

Vol. XXII, No. 2

TABLE 6.
Food of Boleosoma nigrum from inland lakes.

Length in mm.

20-25

25-30

30-35

35-40

40-50

No examined

6

6

10

9

1

Articles of diet:
Copepoda

6.33

6.09

10.1

4.77

30.

Cladocera

20.16

10.33

21.3

11.66

Ostracoda

2.33

3.1

.83

Midge larvae

50.83

54.33

44.5

71.66

10.

Amphipods

6.66

May fly larvae

3.33

10.

2.0

5.55

Caddis fly larvae

10.

Fish remains

3.33

9.

Flat worms

1.2

Round worms

2.

.6

1.33

Filamentous algae

.5

1.33

.6

.2

Diatoms

1.7

.26

Desmids

.33

Sand and silt

4.5

6.66

16.6

4.

50.

TABLE 7.
Food of Boleosoma nigrum from streams.

Length in mm.

15-20

20-25

25-30

30-35 '

35-40

40-50

50-60

No. examined

4

17

20

10

4

4

1

Articles of diet:
Copepoda

40.25

19.04

18.75

12.5

8.25

4.25

Cladocera

8.25

12.4

7.1

1.5

7.25

1.5

Ostracoda

2.64

.4

1.

1.25

Midge larvae

35.75

49.11

50.9

52.3

60.

85.75

40.

May fly larvae

2.

2.94

2.5

12.8

60.

Beetle larvae

7.50

Caddis fly larvae

.5

1.75

Snails

.58

1.5

2.

Fish remains

.3

.5

1.5

Flat worms

.3

1.5

Round worms

.82

.85

.5

Mites

1.

Rotifers

.17

Filamentous algae

.8

Bottom debris

13.75

10.7

15.5

15.1

15.75

6.75

Dec, 1921

FOOD or OHIO DARTERS

49

Summary of Food Habits in Boleosoma nigrum.

1. Entomostraca and minute midge larvae constitute the
chief food of the young. 2. Midge larvae of larger size and may
fly larvae gradually supplant the entomostraca as the fish increase
in size. 3. Organic and inorganic debris forms an important
food item in fishes of all ages. 4. Lake and stream habitats do
not affect the food habits differentially.

D. Cottogaster copelandi Jordan.

Members of this species were taken only from the Bass
Island region of Lake Erie where it was the most universally dis-
tributed of all the darters. The .food habits resemble those of
some of the minnows in that a large amount of vegetable
material and silt enter into the food. Midge larvce and may fly
larvae are most commonly taken, but single specimens have
been taken whose stomachs were entirely filled with debris
and algae. Another distinctive point is the negligible quantity of
entomostraca occurring in the food. This fact, together with
the fact also that ostracoda occur frequently, points toward a
strict bottom feeding habit. It is also notable that there is little
difference in the diet of younger and more mature fish.

TABLE 8.
Food of Cottogaster copelandi.

Length in mm.

23 1 28

30

31

32

34

35

36

37

38

39

40

41

42

44

No. examined

1 1

1

2

3

2

5

3

5

5

5

5

4

5

2

Articles of diet:
Copepoda

2.5

+

19

Cladocera

+

15

1.

+

3.1

Ostracoda

|3.

1.

8.

1.

14.2

.7

May fly larvae

50.

45.

20.

35.

19.

24.

28.

18.

21.4

11.

20.

75.

Amphipods

5.6

Midge larvae

50.

97.

85.

27.5

69.4

40.

44.

62.6

35.

31.4

23.

28.4

7.

20.

25.

Beetle larvae

10.

4.

1.

Fish remains

10.

5.

3.

6.

8.

Fish eggs

3.3

11.

4.6

24.

2.

46.

Mites

5.

Filamentous algae

5.

5.

13,1

5.

2.

1.

14.

+

3.

Bottom debris

15.

5.

12.

15.

25.

23.

27.

12.

78.2

11.

50

CLARENCE L. TURNER

Vol. XXII, No. 2

Summary of Food Habits in Cottogaster copelandi.

1. Midge larvae and may fly larvae are the principal articles
of diet. 2. Comparatively large quantities of algae and bottom
debris are eaten. 3. Entomostraca are taken only in very small
quantities.

E. Boleichthys fusiformis Girard.

This fish was taken mainly in the inland lakes, and in some,
like the Portage Lakes near Akron, it was the most abundant
darter. A few specimens were taken in Lake Erie near Put-in-
Bay, but none were taken from the streams of the state.

TABLE 9.

Food of Boleicthys fusiformis.

Length in mm.

10-15

15-20

20-25

25-30

30-35

35-40

40-50

No examined

1

24

11

9

9

3

5

Articles of diet:
Copepoda

40.

12.83

16.55

2.22

4.44

5.03

.4

Cladocera

60.

22.58

27.36

7.22

8.88

1 66

1.

Ostracoda

9.54

27.27

16.11

7.22

.2

Midge larvae

21.58

17.45

26.70

46.22

10.

30.4

Amphipods

27,25

10 19

13.88

17.33

41.66

11.6

May fly larvae

5.

22.22

4.05

22.

Dragon fly larvae

5.55

8.33

Corixa nymphs

1.66

3.55

6.

Snails

16.

Isopods

31.66

Fish remains

1.11

Round worms

3 33

10.

Insect eggs

1.66

.4

Filamentous algae

.2

1.11

.33

2.

Sand and silt

1.02

1.18

3.33

1.88

1 1.66

An examination of the accompanying table shows that
Boleichthys is a typical darter as far as its food habits go.
Beginning with a diet of pure entomostraca they turn to larger
food as they grow larger. Amphipods, midge larvae and other
larger insect larvaj begin to appear next in the diet while at the
same time the entomostraca become less important in the food.

Dec, 1921

FOOD OF OHIO DARTERS

51

The diet also becomes more complex with the increase in size
of the fish. In all these respects Boleichthys resembles Percina
caprodes. It is remarkable that a fish feeding upon the bottom
and in the midst of so much organic debris should take so little
debris with its food. In sharp contrast to Cottogaster copelandi,
which also feeds upon the bottom but takes large quantities
of debris and algae, Boleichthys like a true but miniature game
fish selects only moving objects for food.

Summary of Food Habits in Boleichthys fusiformis.

1. Entomostraca are the chief food of the smaller specimens
but this gradually gives place to larger objects as the fish grows
older. 2. The diet becomes more complex with the increase in
age of the fish. 3. Amphipods, midge larvae and other insect
larvce become the important articles of food in the older
specimens.

F. Etheostoma flabellare Rafinesque

The food habits of this little game fish present some very
distinctive features. There are only traces of entomostracan
food taken in the smallest specimen. When only 13 mm. in
length its food consists entirely of may fly larvae and the larvae
of midges. The size of the food animals is surprising. Fre-
quently the entire stomach contents was found to consist of a
single larva tightly wadded in the stomach. The larva was
sometimes nearly as long as the fish. The size of the food
increased with the size of the fish when amphipods, beetle
larvae, caddis fly larvae and corixas were taken. Specimens from
the swift streams of the state and those from Lake Erie agreed
closely in their food habits but there was a total absence of
amphipods in the food of stream specimens.

TABLE 10.
Food of Etheostoma flabellare from Lake Erie

Length in mm.

13

14

15

16

17

18

19

20

21

22

23

24

25

26

35

36

37

40

52

No. examined

2

4

3

4

1

8

5

8

5

4

6

2

3

1

2

2

2

4

2

Articles of diet:

Midgelarvae and pupae

3.

3.33

1.2

5.

17.4

5.2

.6

1.2

5.

Amphipods

60.

10.

14.

2.5

16.6

60.

27.5

May fly larvae

97.

100.

6C.6

98.8

40.

95.

72.6

94.8

85 4

96.3

83.4

100.

100.

100.

95.

100.

40.

38.

25.

Beetle larvae

33.8

75.

Flat worms

+

.7

52

CLARENCE L. TURNER

Vol. XXII, No. 2

TABLE 11.
Food of Etheostoma flabellare from streams.

Length in mm.

10-20

20-30

30-40

40-50

50-60

No examined

5

13

5

1

1

Articles of diet:
Copepoda

2.5

Cladocera

1.

Midge larvae

49.

60.7

32,

100,

May fly larvae

47.5

39.3

48.

100.

Caddis fly larvae

8.

Corixa nymphs

12.

Summary of Food Habits in Etheostoma flabellare.

1. The food in the younger stages of the fish consists of may-
fly larvae and midge larvas, the food animals being quite large
and proportionate to the size of the fish. 2. The larger spec-
imens continue to eat may fly larvae, the larvae of midges, the
larvas of other large insects and the adults of amphipods.
3. Amphipods do not appear in the food of the stream inhab-
iting fish.

G. Etheostoma coeruleum Storer

The rainbow darter occurs in swift streams often in com-
pany with Etheostoma flabellare. The food resembles that of
E. flabellare in that may fly larvae and midge larvae are eaten
at all stages after the fish becomes active. Entomostraca are
taken in fairly large numbers in the younger specimens but
they decline in importance as the fish increases in size. Snails,
larger insect larvae, a few small crayfish, midge larvae and may
fly larvce make up the diet of the larger specimens.

Dec, 1921

FOOD OF OHIO DARTERS

53

TABLE 12.
Food of Etheostoma coeruleum.

Length in mm

15-20

20-25

25-30

30-35

35-40

40-50

No examined

2

19

15

7

8

4

Articles of diet:
Copepoda

40.

17.53

6.93

2.62

.25

Cladocera

.37

.46

Ostracoda

.74

.8

Midge larvae

60.

37.

33.35

35.55

25.12

56.25

May fly larvae

41.85

57.33

52.55

46.25

27.50

Large Dipteran larvae

2.

Beetle larvae

3.75

Caddis fly larvae

10.62

Crayfish

12.14

Mites

1.25

Snails

.26

9.28

15.

Sand and silt

.25

.13

1 87

Summary of Food in Etheostoma cceruleiim.
1. Entomostraca are taken to a limited extent by the younger
specimens but are a negligible factor in the food of the older
fish. 2. May fly larvae and midge larvae are the chief food in
all stages over 15 mm. in length. 3. Larger insect larvae, snails,
and crayfish enter into the food of the larger specimens.

H. Etheostoma variatum Kirtland.

Only six specimens of this fish were taken. Three were
taken in Little Darby Creek and three in Big Walnut Creek,
both branches of the Scioto. One was 33 mm. in length, one 34
mm., two were 35 mm., one was 36 mm. and one 58 mm. Not
enough data was secured to warrant any definite statement
concerning their food habits, but many fly larvae and midge
larvae formed the only food of four and the main food for the
remaining two. One had eaten 20 per cent of sand and debris
and the other had taken a few mites in addition to may fly and
midge larvae.

Summary of food in Etheostoma variatum.

1. In six specimens may fly and midge larvae formed almost
the only food.

54 CLARENCE L. TURNER Vol. XXII, No. 2

I. Hadropterus aspro Cope and Jordan.

Eleven specimens of this fish were taken, ranging in length
from 34 to 66 mm. They were taken from the following local-
ities: Miami River near Sidney, Plum Creek east of Ft. Lar-
amie, Big Walnut Creek near Columbus, Black Lick Creek
near Reynoldsburg, Little Darby Creek near West Jefi"erson,
and from Deer Creek.

May fly larvae, midge larvae, corixa nymphs, copepods, fish
remains and silt occurred in the stomachs and were so dis-
tributed as to leave the impression that there was no prevalent
food for a fish of any given length. For example, a 34 mm.
specimen had eaten only midge and may fly larvae, a 39 mm.
specimen had eaten 100 per cent of copepods and a 40 mm.
specimen had eaten corixa nymphs and small fish. A 66 mm.
fish had eaten 60 per cent of copepods, 38 per cent of may fly
larv£e and 2 per cent of silt. Corixa nymphs were eaten only by
those from Deer Creek and those containing a large per cent of
copepods in their stomachs all came from Big Walnut and
Black Lick Creeks.

Summary of Food in Hadropterus aspro.
1. The food is quite variable, may fly larvae, midge larvae,
copepods and corixa nymphs being the most important food
animals. 2. There seems to be no change in the food habits of
specimens ranging from 34 mm. to 67 mm. 3. There is some
evidence that Hadropterus is a random feeder, taking within
certain limits whatever chances to be present.

J. Hadropterus phoxocephalus Nelson.

This rather rare species was taken only twice. A 53 mm.
specimen was taken from the Miami River near Sidney and a
57 mm. specimen from Black Lick Creek three miles north of
Reynoldsburg. As in H. aspro the principal food animals were
midge larvae, may fly larvae and copepods.

K. Ammocrypta pellucida Baird.

Three specimens of this fish were examined. A 36 mm.
specimen from Middle Bass Island near Put-in-Bay had eaten
90 per cent of midge larvae and a little silt. One 24 mm. spec-
imen from the west branch of the Mahoning River had taken
only midge larvae and one from Beaver Creek near Celina had
eaten a little sand and several midge larvae.

Dec, 1921 FOOD of ohio darters 55

COMPAR.\TIVE FOOD HABITS OF DIFFERENT SPECIES.

The darters belong to the family Percidas and so are most
nearly related to the perch and the pike perch. The darters
are a specialized group and so far as the food habits of the
young go, there is such a variety of behavior that it is difficult
to select a typical mode. The perch is a generalized fish on the
other hand and it is practically certain that the darters descended
from an ancestral perch-like fish. In seeking for a near relative,
therefore, with which to compare the darters we naturally turn
to the perch. In this fish there are three well recognized but
intergrading stages of food habit depending upon age. The
very young subsist almost entirely on entomostraca, turning
gradually to amphipods and insect larvae — mainly midge and
may fly larvae — while the proportion of entomostraca dimin-
ishes. Still later, in the yearling and two-year-old perch the
diet becomes very complex but there is a predominance of
amphipods and large insect larvae in the food. Snails and veg-
etable material are also eaten in considerable quantities. These
three stages in the food habits of fishes have been shown by
Forbes to exist in the perch and in many other fishes, especially
the Centrarchidae which are closely related to the darters and
they have been designated as infancy, youth and maturity. In
examining the records of the food of the darters to select those
showing a typical habit, the three periods are borne in mind
and those fish are selected which most nearly conform to this
type of habit.

Of the eleven species examined, Percina caprodes most
nearly meets the specifications of generalization in its food
habits. The periods of infancy and of youth are well marked
and the period of maturity is marked by an omnivorous habit.
It would also be expected also that a fish with a generalized
food habit would find survival easy and would therefore be
abundant and uniformly distributed. All these requirements
are met, indeed the distribution of Percina was identical with
that of the perch in many places.

Boleichthys may also be ranked as generalized in its food
habits. Beginning with entomostraca in the 12 mm. stage, it
changes rapidly to amphipods and insect larvae, never giving up
the entomostraca entirely even in the 50 mm. stage. Then it
passes to maturity, where the boundary is not so well marked.

56 CLARENCE L. TURNER Vol. XXII, No. 2

but may be recognized by the greater proportion of large sized
food animals such as snails, isopods, dragon fly larvae and
corixa nymphs.

Diplesion blennioides passes over the stage of infancy very
quickly and begins eating the food characteristic of youth by
the 20 mm. stage. There is a strong tendency to take only
may fly and midge larvae on the part of the specimens from
Lake Erie, while those from the streams pass into a typical
maturity in which the diet becomes more complex and large
insect larvag are taken. It must be admitted, however, that if
complexity of diet is to be taken as a criterion of maturity,
Diplesion reaches maturity by the time that it has reached the
25 mm. stage.

Boleosoma ?iignim begins a mixed diet very early (15 mm..).
Entomostraca and minute midge larvae continue to appear in
the food through life indicating that the habits of infancy are
never entirely given up. There is a marked utilization of debris
also which does not occur in any other darter except Cottogaster
copelandi.

Cottogaster copelandi. No specimens under 28 mm. in length
were examined so that it is impossible to give any data con-
cerning the stage of infancy. The period of youth is well sus-
tained up to the 43 mm. stage and in addition there is the de-
velopment of two habits that mark this group as a specialized
one. These habits are the eating of bottom debris and vegeta-
tion and the consumption of fish eggs.

Hadropterus as pro. Nothing can be offered as to the habits
of infancy in this fish, but the persistence of copepods, midge
larva; and may fly larvae up to 66 mm. specimens points to a
retention of the habits of infancy and of youth in the mature
stage. It resembles Boleosoma nigrum and Diplesiofi hlefinioides
somewhat in this respect.

Etheostoma. This genus as represented by the three species,
flabellare cceriileum and variatiim is characterized in its food
habits by its resemblance to the mature game fishes. Vegeta-
tion and debris are seldom taken and from the earliest stages
(10 mm. in flabellare) they capture and eat food animals that
are very large in proportion to the fish eating them. Midge
larvae, may fly larvae, beetle larvae and corixa nymphs are some
of the animals eaten. E. flabellare shows the greatest degree of
specialization in this direction with E. cceriileum resembling it

Dec, 1921 FOOD of oitio darters 57

somewhat. There is a tendency also to omit entomostraca from
the food of infancy and to take larger insect larvae at once.
E. cceruleum resembles the more generalized darters in this
regard, having a large proportion of copepods up to the 15 mm.
stage.

The length of the fish has been taken to indicate its age
throughout this discussion but it is recognized that the rela-
tionship is only relative, especially when comparing members
of different species. Thus it appears that E. flabellare has
passed into the stage of youth by the time that it has gained a
length of 10 mm. but Percina caprodes does not pass into this
stage as indicated by its food habits till it reaches a length of
25 mm. After studying P. caprodes, therefore, one is likely to
fall into the error of considering the much smaller specimens of
E. flabellare as correspondingly younger. Indeed, it may be an
error in this paper to have stated that the stage of infancy in
Etheostoma is poorly represented, for it is possible that specimens
may be found which are less than 10 mm. in length and which
eat entomostracan food.

Summary of Comparison of Food Habits.

The darters may be divided roughly into three classes based
upon the character of the food at the different periods in their
lives. First : a group with generalized food habits such as those
found in the perch and the sunfishes. In this class three periods
are to be recognized in the life of an individual ; infancy, when
the food consists of entomostraca and minute midge larvae,
youth, in which may fly larvae, small midge larvae and small
amphipods form the food, and maturity during which period
the food is varied and is likely to contain a large proportion of
large insect larvae, large amphipods and snails. Second: one in
which the period of youth is shortened or omitted and the
adults subsist to a considerable extent upon vegetation and
debris. Third: a group of miniature game fishes which begin
at a very early stage to hunt for large may fly larv«, midges and
other active larvae. The period of infancy is curtailed so much
as to seem entirely absent or is merged with youth. The habit
of taking large food animals continues to the adult stages and
the habit is accompanied by an unwillingness to take either
debris or vegetation.

58 CLARENCE L. TURNER Vol. XXII, No. 2

To the first group belong Percina caprodes and Boleichthys
fusiformis. To the second belong Cottogaster copelandi and
Boleosoma tiigrum, while Etheostoma variatum, E. ccBruleum and
E. flabeUare comprise the third. Diplesion blen?iioides, Hadrop-
terus aspro and H. phoxocephalus are related to both groups one
and three and Animocrypta pellticida resembles group three.

FACTORS GOVERNING FOOD CHANGES.

{a) Age and Size of Fish.

It is obvious that the smaller fish must be limited in their
selection of food to such a size as it is physically possible for
them to capture, while the larger ones have a greater possibility
of choice. Since the size of the fish is dependent on its age, the
age must enter into this principle. Records were kept of the
size of the food animals taken by Percina caprodes, Etheostoma
cceruleum, E. flabeUare and Boleichthys fusiformis and this
record compared with that of the length of the fish. A close
degree of similarity was found between the size of the food
animals and the size of the fish, which was quite independent
of the character of the food.

(b) Seasonal Position of Food Animals.

Whether the body of water in question is a stream, a small
lake or a large lake such as Lake Erie, there is a season cycle
in the fauna and the flora. Phyto-plankton develops which
furnishes the food for the minute crustaceans and their larvae
and for the larval forms of some insects. Submerged and float-
ing vegetation develops which furnishes food and a retreat for
insects, crustaceans and young fish all of which are important in
the food relations of the darters. With the warming of the
waters winter eggs of various forms hatch and the young forms
produced are also important as food animals. Even eggs of
insects and of fishes furnish food at certain seasons. Like all
other fishes the darters are dependent for the amount and vari-
ety of their food upon the seasons in which they develop.

(c) Special Structures.

Forbes has pointed out that those fishes that retain the
habit of feeding upon minute organism in their adult stages are

Dec, 1921 FOOD of ohio darters 59

equipped for the purpose with fine gill strainers. Some of the
darters feed upon entomostraca to some extent in the adult
stage but there are none that may be classed as feeding exclu-
sively upon very small objects. An examination of the gill
strainers in the different species listed here failed to show any
marked differences.

The position of a terminal mouth, especially if the lower
jaw is projecting, also seems to be correlated definitely with the
habit of taking large and active food. Etheostoma flaheUare is
the most specialized in the development of a projecting lower
jaw and it has developed the habit of taking large, active food
animals more than any other. Etheostoma coeruleum is some-
what less specialized in both its food habits and the devel-
opment of a terminal mouth but it resembles E. flabellare.
Boleichthys fiisiformis was taken in a situation where vegetation
and debris were most abundant, but a very small trace of either
appears on the food. It is a remarkably clean feeder for the
environment and seems to have developed nothing of the grub-
bing habit, although it is bottom feeder.

{d) Special Habits.

All of the darters are considered to be very agile fish, but
even among the members of an active group there are some
that are more active than others. The difference in the ability
ot the fish to overtake and seize food animals would be reflected
in the food. Of the list given here Etheostoma flabellare is the
most active and the large, active food animals that appear in
the diet are not taken by any other darter.

The habit of feeding upon the bottom seems to be well
established in the adults of most species but there is a differ-
ence even here. Some of the fish have developed a habit of
grubbing upon the bottom so that a large amount of debris
appears incidentally in the food. Boleosoma nigrum is one of
this sort. Others may live in the midst of debris and select only
live, active food. Boleichthys Jusiformis illustrates this type.

Percina caprodes in its very early stages is a surface feeder
like the younger stages of the perch and black bass but as it
matures it becomes a bottom feeder. Others like Etheostoma
flabellare and Boleichthys f.iisijormis seem to be bottom feeders
from the time that they hatch. This difference in habits has its

60 CLARENCE L. TURNER Vol. XXII, No. 2

effect upon the food ; the diet of the young P. caprodes consists
of copepods and cladocera while E. flahellare and B. fusiformis
take, in addition to copepods and cladocera, midge and may fly
larvae and ostracods.

{e) Different Habitats.

Some of the darters are very limited in their habitats.
Although a few seem to occur almost anywhere that a fish
might be expected to live. Cottogaster copelandi, for example,
was taken only in Lake Erie; Etheostoma cceruletim was con-
fined entirely to swift streams, but Etheostoma flabellare,
Diplesion blennioides, Ammocrypta pellucida, Percina caprodes
and Boleosoma nigrum were found in both Lake Erie and the
streams of the state. P. caprodes and B. nigrum may be expected
in almost any body of water except in isolated pools. It is
obvious that the small animal life of a swift stream and of a
lake choked with vegetation must differ and fishes confined to
such habitats must also differ in their food habits. Such a
dift'erence is much less than might be expected, however.

Percina caprodes, Etheostoma flabellare and Diplesion blen-
nioides occurring both in Lake Erie and in the streams of the
state afford data for a comparative study of the food of the
same species of fish in different habitats. Amphipods form an
important item of food in the lake specimens of both E. flabellare
and P. caprodes, but they do not occur in the food of stream
dwelling forms. Midge larvee and may fly larvas are found in
the food of both stream and lake specimens, but species dif-
ferences are common. The same is true of the molluscan diet.
Planorbis and Physa were the snails utilized as food in lake
specimens but the fiat gastropod, Ancylus, was the only snail
found in the food of stream darters. Some specimens of P.
caprodes were found which had taken as many as thirty of the
latter snail.

FOOD AND DISTRIBUTION.

With the exception of Boleichthys fusiformis, all the darters
mentioned in this paper seem to be rather generally distributed.
Boleichthys has been taken only in the northern part of the
state, but there is no peculiarity in the food which could account
for this geographical limitation. Locally, however, the char-
acter of the food probably determines the range and distribution

Dec, 1921 rooD of ohio darters 61

of the fish. Taking the food that they do and having the food
habits which are characteristic of them, it would not be
expected that Etheostoma flabellare and E. ccerideum would be
found in stagnant water. Nor on the other hand, would it be
expected that there would be found species like Cottogaster
copelaudi in swift brooks, when it is given to eating large
proportions of vegetation and debris.

If any fish were able to adapt itself to several kinds of hab-
itats, it should be one of generalized habits, for specialized
habits whether food, reproductive or otherwise, limit the scope
of any animal. The wide range, uniform distribution, and
common occurrence of Percina caprodes are no doubt partly
due to the fact that the animal is unspecialized and is able to
become adapted to various habitats. The change in food
habits as Percina becomes a stream dweller, when it was
formerly a lake fish, may be cited as an instance of such an
adaptation in food behavior.

SUMMARY.

1. The food of the Ohio darters varies with the fishes. In
the most typical cases the young feed exclusively upon ento-
mostraca, turning to midge larvae and other small insect larvas
later, and when mature feeding upon a varied diet in which
ephemerid larvae and other large insect larvae predominate.
The fish with the most typical food habits is Percina caprodes.

2. Some of the darters vary from this habit of eating insect
larvas in the younger stages b}^ apparently omitting the ento-
mostraca from the first stage. These fish are characterized,
even in the adult, by the large size of the food animals taken.
Etheostoma flabellare is the most specialized in this regard with
Etheostoma ca;rideiim resembling it.

3. Other darters after passing through a rather typical
first and second stage eat a large percentage of vegetable
material and organic debris in their older stages. Cottogaster
copelandi is the most typical one of this group.

4. Amphipods occur regularly in the food of most lake
specimens but are entirely lacking in those from streams.

5. When members of a species are taken from both streams
and lakes there is a marked difference in the food animals
although there is usually a close adherence to the typical food
habit.

62 CLARENCE L. TURNER Vol. XXII, No. 2

6. Factors governing the food of the darters are: (a) The
age and size of the fish; (b) Seasonal position of food animals;
(c) Special structures in the fishes (terminal or ventral mouth,
etc.); (d) Special types of behavior of the fish; (e) Different
habitats.

7. Different food habits are not sufficient to account for the
distribution of the Ohio darters except locally.

LITERATURE CITED

Forbes, S. A.

1878. The Food of Illinois Fishes. Illinois State Laboratory of Natural

History, Vol. 1, Bull. 2, p. 71.
1880. The Food of Fishes. Ibid, Vol. 1, Bull. No. 3, p. 66.
1880. On the Food of Young Fishes. Ibid. Vol. 1, Bull. No. 3.
1880. Food of the Darters. American Naturalist, Vol. 14, p. 697.

On the Food Relations of Fresh-water Fishes. Ibid. Vol. 2, p. 475.

OsBURN, Raymond C.

1901. The Fishes of Ohio. Ohio State Academy of Science. Special paper
No. 4.

Pearse, a. S.

1918. The Food of the Shore Fishes of Certain Wisconsin Lakes. Bulletin
Bureau of Fisheries, Vol. 35, Document No. 856.

Pearse, A. S. and Achtenberg, Henrietta.

1920. Habits of Yellow Perch in Wisconsin Lakes. Bulletin Bureau of
Fisheries, Vol. 36, Document No. 885.

Turner, C. L.

1920. Distribution, Food and Fish Associates of Young Perch in the Bass
Island Region of Lake Erie. Ohio Journal of Science, Vol. XX, No. 5.

NOTES ON THE DODDER GALL WEEVIL,
SMICRONYX SCULPTICOLLIS CASEY

HARRY B. WEISS and ERDMAN WEST
New Jersey Department of Agriculture

Numerous galls were noted on dodder, CusciUa cephalanthi
Eng., at Monmouth Junction, N. J., during the first part of
August. Upon collecting and cutting some of the swellings
open, several beetles were obtained. At this time most of the
galls contained larvae and a few pups. The adult was identified
as Smicronyx sciilpticollis which identification was confirmed
later by Mr. C. W. Leng. During the last of August quite a
few of the galls contain adults nearly ready to emerge; in
fact a few beetles will have emerged by this time. However,
most of them leave the galls during the first half of September
and later in central New Jersey, emergence taking place
through a circular opening in the side.

Each gall is single celled and consists usually of a broadly
fusiform or subglobular enlargement of the peduncle of the
flower cluster, which normally is comparatively thick and
fleshy. (Text figure 1.) Many galls were noted which appeared
to be enlarged nodes. The completed galls were for the most part
subglobular in shape and about four to six millimeters in diam-
eter, while the younger ones were broadly fusiform as a rule. In a
few cases the galls were quite irregular due to having been pressed
out of shape by contact with the host of the dodder or to
having been constricted by the dodder itself. The galls are light
yellow to orange in color, a few being somewhat greenish.

Larva. Length about 2.25 mm. Form subcylindrical, slightly
curved, tapering slightly at both ends; sparsely hairy, hairs short; color
light yellow, head light brown. Head small, subcircular, slightly
depressed; collum absent; epicranial halves separated dorsally by a
very faint median suture; front triangular; gula indistinct, membran-
ous; ventral mouth parts fleshy; clypeus and labrum distinct, former
transverse; antennae minute almost obsolete; ocelli absent. Mandibles
of biting type, broad across base, bifid at tip with a comparatively
minute tooth below the two terminal ones. Maxilla fused with labium
to near apex; lacinia simple, fringed with chitinous hairs on inner sur-
face; galea absent; maxillary palpi two-jointed, labium fleshy with

63

64

HARRY B. WEISS AND ERDMAN WEST Vol. XXII, No. 2

mentum and submentum fused, indistinct; labial palpi one jointed.
True legs absent indicated by ambulatory tubercles. Thoracic and
abdominal segments each with three dorsal plicae. Cerci absent. Anal
segment wart -like.

Pupa. Length about 2.25 mm. Light yellow, oval. Head and beak
bearing several minute hairs. Prothorax dorsally bears a row of about
twelve distantly placed chitinous hairs on anterior, lateral, and part
of posterior edges; a pair of similar hairs on middle dorsal portion of
prothorax; meso thorax with a pair of shorter chitinous hairs arising
near posterior lateral edge; metathorax with a similar pair arising from
middle lateral portion; each abdominal segment with a transverse
dorsal row of distantly placed chitinous hairs ; abdomen terminated by
a pair of outwardly directed chitinous spines. All hairs arising from
tuberculate bases.

Galls on the Dodder, Cusciiia cephalanthi

Adult. Smicronyx sculpticollis. This was described by
Casey from Indiana, Virginia and Texas. (Ann. N. Y. Ac. Sci.
VI, p. 403, 1892). According to Blatchley and Leng (Rhynch
N. E. Amer., p. 218) it is known to occur in New Jersey, Long
Island, District of Columbia, Illinois, Kansas and Iowa. In
Smith's Insects of New Jersey it is recorded from Clementon,
August 9, and Sea Isle City, June 11. Blatchley and Leng
state that this species is distinguished from its nearest allies
by the small densely punctured thorax, narrow hair-like scales

Dec, 1921 THE DODDER GALL WEEVIL 65

and almost wholly dull red elytra. Many of our specimens had
black elytra except for a pale, reddish-brown, broad stripe
extending from humerus to apex. The extent of the black or
reddish -brown areas appears to vary slightly. It was noted
that immature beetles w^ere almost wholly reddish-brown, the
black first appearing along the suture and later spreading
laterally.

In Rhynchophora of North Eastern America under the
species Smicronyx tychoides Lee, (p. 218) there appears the
statement, "said to have been bred from galls on dodder,
Cuscuta gronovii, by Zabriskie" and it is quite probable that
this record refers to sculpticollis especially as "specimens named
tychoides in the Leng collection from Long Island proved to be
sculpticollis.

OHIO ACADEMY OF SCIENCE

ANNUAL MEETING

At a meeting of the Executive Committee, held on December
17th, it was decided to hold the next Annual Meeting of the
Ohio Academy in Columbus, April 14th and 15th, 1922. The
preliminary notice of the meeting will be mailed by the Sec-
retary about the first of March.

Edward L. Rice,

Secretary of the Academy.

67

The Ohio Journal of Science

Vol. XXII January, 1922 No. 3

A SYNOPSIS OF THE GENUS STENOCRANUS,

AND A NEW SPECIES OF MYSIDIA.

(HOMOPTERA).

H. L. DOZIER
State Plant Board of Mississippi

The genus Stenocranus was founded by Fieber in 1866 and
since that time three species have been placed in it from Europe,
minutus Fab., fuscovittatus Stal. and longipennis Curt., Macul-
ipes, described from South America by Berg in 1879 from a
single female, has never been recognized since. In 1914,
Crawford in his "Contribution towards a Monograph of the
Delphacidas" described angiistus from British Honduras, rostri-
frons from Cuba, and similis from Alabama.

Stenocranus croecus of Van Duzee is now wrongly placed in
the genus Kelisia and sacchar Ivor lis of Westwood does not seem
to belong here. At present there are eight species described
from the New World and the following paper brings the
total up to twelve.

As the original descriptions are widely scattered, for the
most part in publications not readily accessible to the ordinary
worker, it seems advisable at this time to review the genus,
describing the new species and giving comparative outline
drawings of heads and the male genitalia, all drawn to the
same scale.

All of the species, so far as known, with the exception of
similis, occur on coarse grasses, rushes and sedges in swampy
and boggy places. Similis, however, occurs abundantly on the
bamboo-cane, Arundinaria tecta.

Nearly all of the members of this genus are of a pale straw
to brown color with a more or less distinct dorsal whitish

69

70 H. L. DOZIER Vol. XXII, No. 3

median vitta that runs from the vertex, over the thorax and
scutellum, and is continued on the elytra by the pale com-
misural nervures. The legs are usually lineated with fuscous.

The genus may be briefly characterized as follows: Body slender,
rather long. Head together with the eyes narrower than pronotum;
vertex more or less elongate, slightly converging to apex, somewhat
rectangular, and produced from one-fourth to two-thirds its length
beyond the eyes; frons long and narrow, slightly broader at apex than
at base, tricarinate. Eyes more or less compressed, not deeply emargi-
nate below. Antennae rather short, first segment shorter than the
second, the latter usually somewhat tuberculate. Thorax slender;
lateral carinse usually attaining the hind margin; scutellum tricarinate.
Calcar tectiform, the margins usually rather close together with
pubescence between. Female ovipositor sheath subcylindrical, often
broadened or foliaceous and appressed to genital segment. Probable
type of genus is Stenocranus minutus Fab.

From the present study it seems that the final criterion for
specific determination in most of the species is an accurate
figure of the male genitalia. This character is constant within
the species and quite distinctive.

Figures I and II are the work of Wm. P. Osborn of Syracuse
University.

KEY TO THE SPECIES OF STENOCRANUS.

1. Calcar usually large and foliaceous; vertex much produced beyond eyes. . . .2
Calcar not unusually large, seldom foliaceous; vertex shorter 3

2. Frons pale, with a brown band below antennae; first antennal segment

only a little shorter than the second palaetus V. Duzee

Frons without band; first antennal segment about as long as the second,

longicornis Dozier

3. Female ovipositor sheath broadened conspicuously, not styliform or

cylindrical 4

Female ovipositor sheath more or less cylindrical, at least on apical
two-thirds 8

4. Frons narrowed above, sides subparallel from ocelli to apex; vertex not

produced more than one-third its length beyond eyes 5

Frons broadest at apex, sides uniformly diverging from base; female
ovipositor sheath less foliaceous, narrower 7

5. Vertex not more than one and a half times as long as broad posteriorly;

frons usually less than three times as long as broad 6

Vertex at least twice as long as broad; frons narrow, fully three times as
long as broad, or more, black between carinae angustus Crawford

6. Female ovipositor sheath broadly elliptical, broadest midway; frons

usually black between carinae dorsalis Fitch

Female ovipositor sheath slightly narrower, broadened apically, not as

closely appressed as in dorsalis vitlatus Stal

Female ovipositor sheath broadest apically, pyriform; frons pale brown

between carinae; vertex and frons relatively shorter felti V. Duzee

7. Vertex produced considerably more than half its length before eyes,

beak-shaped, fully four times as long as broad rostrifrons Crawford

Jan., 1922 synopsis of the genus stenocranus 71

8. Male pygofer rather long and narrow, with ventral margin deeply and

acutely angled emarginate; genital styles long and slender, .breviceps Dozier

Male pygofer comparatively small; genital styles large at base, narrowing
only slightly beyond middle and enlarging distad, with inner tip pointed,

croceus Van D.

Male pygofer medium sized, excavated into a large median spur and two
lateral ones; anal tube with a long sharp median process on ventral
margin hinei Dozier

Male pygofer large, ventral margin roundingly emarginate; anal tube
long, produced ventrad into two much longer processes than in dorsalis;
genital styles large, constricted one-third of length from base, distal
third converging to acute apex similis Crawford

Stenocranus dorsalis Fitch.
(1851 Homop. N. Y. St. Cab., p. 46).

Many species bear a close resemblance to dorsalis and are
often confused with it on superficial examination. The gen-
italia are quite distinct and characteristic in both sexes and
afford the most sure means of specific determination.

Head narrower than pronottim, strongly carinate. Vertex long and
narrow, about one and a half times as long as broad posteriorly, pro-
duced about one-third its length beyond the eyes. Front long and
narrow, narrowed above, slightly but quite abruptly broadened to
ocelli, thence parallel to apex; median carina sometimes forked a little
below apex of head. Antennas rather short, the second segment three
times as long as the first. Pronotum moderately long, scarcely as long
as the vertex, lateral carinas arcuate, attaining the hind margin. Scu-
telltun about twice as long as pronotum, tricarinate. Elytra long and
narrow. Calcar large, half as long as the basal tarsus, somewhat
pubescent.

General color light yellowish-brown to brown, the dorsum iisually
with a long whitish vitta that extends from the vertex to the tip of
scutellum and is continued by the whitish margin of the clavus when
the elytra are closed; this vitta is variable in distinctness and width.
Front and clypeus with the intra-carinal spaces black. Antennae pale.
Elytra usually subhyaline, light brown, occasionally darker, with a
more or less prominent brown macula along membrane slightly behind
middle and often extending somewhat on to corium. Sexes similar in
coloration. Legs pale; femora and tibise striped with fuscous.

Female ovipositor sheath greatly broadened, foliaceous, closely
appressed to and entirely covering genital segment, elevated on margins,
and often covered with fioccous secretion.

Male pygofer large; anal tube with two long, acute processes on
ventral margin; genital styles large at base, abruptly narrowed midway,
thence deeply emarginate, sinuate, acute at tip.

Length of body, 2.50-3 mm. ; length to tip of el}d:ra, 4.50-5 mm.

Redescribed from a large series from many states. This is
our most common and most widely distributed species of the
genus, being found abundantly on sedges over most of the
United States and Canada.

72 H. L. DOZIER Vol. XXII, No. 3

Stenocranus vittatus Stal.
(1862 Berliner Ent. Zeits., VI, p. 315).

This species, described from Carolina and Pennsylvania by
Stal as Delphax vittatus, has not since been recognized. I have
on hand a single female, collected at Gainesville, Fla., by the
writer in 1917, a series of four females and two males collected
by C. J. Drake at the same locality. May 5, 1918, one male
from Hattiesburg, Miss., Aug. 10, 1921, and a series of two
males and a female taken by the writer sweeping grass and
sedges in a swamp near Meridian, Miss., Aug. 14, 1921, that
I place as this species.

Although very strongly resembling dorsalis and probably long
confused with that species, it is quite distinct and is easily distinguished
by its smaller size and the shape of the male genital styles.

Identical in structure and wing venation with dorsalis. General
color darker brown with the median white dorsal vitta very distinct
itself and made very prominent by the deeper fuscous of the pronotum,
scutellum and elytra. Intra-carinal spaces of front and clypeus dark
fuscous. Antenna pale. Elytra of a much darker fuscous on corium
than in dorsalis and there is a dark brown macula towards apex, with
the apical nervures prominently infuscated. Tergum of female marked
with fuscous and red, darker in male. Femora and tibiae lineated with
fuscous.

Female pygofer pale fuscous, broad, foliaceous, greatly resembling
that of dorsalis, but broadest apically and not so closely appressed to
the genital segment.

Male pygofer fuscous, comparatively smaller than in dorsalis;
genital styles broad at base, abruptly narrowed almost midway, thence
deeply emarginate, and then roundingly drawn out to acute tip; anal
tube with two acute lateral processes on ventral margin.

Length of body, 2.25 mm. ; length to tip of elytra, 3.50-4.25 mm.

I include here the original description in Latin and a transla-
tion of the same :

''Delphax vittata Stal. — griseo-straminea, supra infuscata; fronte
clypeoque fuscis, pallido-carinatis ; vitta verticis thoracis scutellique
nee non commissura pure stramineis ; tegminibus fuscescentibus apicem
versus obscurioribus, maculis duabus parvis marginis commissuralis
prope apicem, parteque lata costali subvinaceo-hyalinis, venis trans-
versis apicalibus hujus partis fuscis et fusco-marginatis ; capite modice
prominente. 9 . Long, cum tegm. 5 millim.

"Patria: Carolina meridionalis et Pennsylvania. (Mus. Holm.)."

Delphax vittata Stal. — gray-stramineous, infuscated above; frons
and clypeus fuscous, palely carinated; the vitta on vertex, thorax, and
scutellum bright stramineous and also the commisure, stramineous.
Tegmina fuscous, rather obscure towards the apex, with two small

Jan., 1922 synopsis of the genus stenocranus 73

spots on the commisural margin near apex, and a wide part of the costa
somewhat wine-colored-hyaHne, transverse apical veins of this part
fuscous and margined with fuscous. Head moderately prominent.
Female. Length with tegm. 5 mm.

Country: South CaroHna and Pennsylvania. (Mus. Holm.).

Stenocranus feiti Van D.
(1910 Trans. Am. Ent. Soc, xxxvi, p. 88).

Closely allied to dorsalis, differing principally in having the
apex of the vertex broader and more rounded, the front pro-
portionately broader and shorter, and the pygofer of female is
much broader apically and almost pyriform.

Head decidedly narrower than the pronottmi. Vertex produced
about one-third its length beyond the eyes, carinas distinct. Front long
and narrow, sides subparallel, narrowed towards base tricarinate.
Antennas with second segment about three times as long as the first;
seta short. Pronotum as long as the vertex, tricarinate, the lateral
carince attaining the hind margin. Scutellum short, about one and a
half times as long as the pronotum, tricarinate. Elytra comparatively
very short and broad and are held in a more or less roof-shaped position.
Calcar slender.

General color a soiled yellowish-testaceous with the carinse a little
paler and the dorsum marked with a whitish vitta from near the front
of the vertex to the tip of the scutellum, which is continued by the pale
commisural nervure of the closed elytra. Front with the intra-carinal
spaces pale brown or almost concolorous. Basal segment of antennae
with a black mark inferiorly, a similar mark on the cheek below the
ocellus, and the antennal socket has a distinct black marginal spot
anteriorly. Venter in the male black with the segments edged with
orange. Elytra in the female pale yellowish hyaline with the nervures
a little darker, sometimes becoming almost black on the clavus and
inner margin of corium; the second apical nervure and the apex of the
others deep black. In the male the nervures are almost entirely
blackish fuscous, and the black of the second apical ner\^ure is spread
over the adjoining areole. Legs lineated with fuscous.

Female ovipositor sheath broadest apically, pyriform, fuscous,
foliaceous, closely appressed to and covering the genital segment; anal
style large and fuscous.

Male pygofer light brown in color, base fuscous, large, with ventral
margin roundingly excavated; genital styles reddish-brown, large at
base and pointed on either side about middle, then roundingly and
abruptly emarginate, narrowed and drawn out to an acute tip; anal
tube with a sharp, reddish-brown tooth each side.

Length of body 3 mm. ; length to tip of elytra, 4-5 mm.

Redescribed from a series of males and females taken at
Cranberry Lake, N. Y., July 5, 1917, by C. J. Drake, and a

74 H. L. DOZIER Vol. XXII, No. 3

female from Orono, Maine, taken May 31, 1914, by H. M.
Parshley. Also known from New Hampshire. This species
occurs in low wooded swamps and bogs.

Stenocranus similis Crawford.
(1914 Proc. U. S. Natl. Mus., xlvi, p. 591, two figs.)

Female of similar color and about the same size of dorsalis
which it very closely resembles superficially. The usual white
vitta is seldom or indistinctly present.

Fig. 1. Female of Stenocranus similis

Head narrower than pronotum. Vertex long, wider at base and
narrowed towards the apex, produced about one-third its length beyond
the eyes, carinas distinct. Frons long and narrow, tricarinate. Second
antennal segment three times as long as first; seta fuscous, twice the
length of the second segment. Pronotum slightly shorter than vertex,
tricarinate, the lateral carina well-rounded and attaining the hind
margin. Scutellum over one and a half times as long as pronotum,
tricarinate. Calcar large, but rather slender.

General color light yellowish-brown with the usual white dorsal
vitta generally missing or very indistinct. Intra-carinal spaces of
front and apex of vertex light to dark fuscous. Antennas pale. Eyes
pale yellowish-brown to fuscous. Elytra subhyaline, usually light
yellowish -brown, a fuscous spot on inner margin at junction of claval
and commisural veins; radio-medial cross-vein and apical ones at their
tips, infuscated. In the male the tip of the elytron, beginning with
the cross-veins, is deeply infuscated, forming a large round spot.
Abdomen pale in female, more infuscated in male. Legs lineated with
fuscous.

Female genital segment longer and narrower than in dorsalis;
ovipositor sheath not foliaceous, cylindrical and extending almost to
tip of abdomen.

Male pygofer large; anal tube long, produced ventrad into two
much longer processes than in dorsalis; anal style short; genital styles
large, constricted one-third of length from base, distal third converging
to acute apex.

Jan., 1922 synopsis or the genus stenocranus 75

Length of body, female, 3 mm.; male, 2.75 mm.; length to tip of
elytra, female, 5 mm.; male 4.25 mm.

Redescribed from a large series of males and females col-
lected in Mississippi by the writer at Aberdeen, June 26, 1921,
Columbus, June 23, 1921; Tupelo, July 2, 1921; Fulton, July 4,
1921; and Rokeena, July 20, 1921; and two females taken at
Clemson College, S. C, by G. G. Aineslie. These were all
swept in abundance from cane-brake and the only definitely
known host plant is the bamboo-cane, Arundinaria tecta.

Stenocranus palactus Van D.
(1897 Bui. Buf. Soc. Nat. Sci., v, p. 232).

Form and size of dorsalis. Distinguished by its long vertex
and large, foliaceous tibial spur and banded frons.

Head decidedly narrower than pronotum. Vertex extended half
its length beyond the eyes, carinae prominent except median one, which
is faint. First antennal segment a little shorter than the second.
Pronotum slightly shorter than the vertex, strongly tricarinate, the
lateral carinas attaining the hind margin. Scutellum one and a half
times as long as pronotum, tricarinate, the lateral carinte rather indis-
tinct. Calcar unusually large and foliaceous.

Color is fulvous yellow above, paler beneath. Frontal fovse inter-
ruptedly black over the apex of the head from the base of the antennas
to the middle of the vertex; front crossed by a brown band below the
antennae, and another crossing the base of the clypeus and extending
over the anterior coxas and pleural pieces; apex of front and its median
carina interruptedly pale. Antennas somewhat fuscous. Eyes black.
Elytra subhyaline, nervures yellowish, the commisural white with a
brown line before the apex of the clavus ; inner sector of the corium and
the apical nervures, except the base of the two outer, fuscous; a smoky
cloud covers the anastomosis at the base of the middle apical areole
and spreads feebly over the inner area of the membrane. Tergum
brownish. Legs pale, femora lineated and the tibiae banded with
fuscous.

Female genitalia typical. Male pygofer trilobate, middle lobe with
a somewhat semicircular median notch, each side of which is extended
tooth-like; lateral lobes, genital styles, and anal style dark fuscous;
anal tube without ventral processes.

Male slightly smaller than female, with slightly shorter vertex;
otherwise similar in appearance.

Length of body, male, 2.75 mm. ; female, 3.50 mm. ; length to tip of
elytra, male, 4 mm. ; female, 4.9 mm.

Redescribed from two males and two females taken at
Gainesville, Fla., May 5, 1918, by C. J. Drake; one female

76 H. L. DOZIER Vol. XXII, No. 3

from Perkinston, Miss., taken June 25, 1921, by F. H. Ben-
jamin; and a female from Ocean Springs, Miss., June 28, 1921.
Nothing is known of its food plant or habitat.

Stenocranus longicornis sp. nov.

Very closely allied to S. palcetus both in general appearance,
large tibial spur, and genitalia but differentiated at once by the
very long antenna and distinct male genitalia.

Vertex proportionately long, produced beyond the eyes slightly
more than a third its length, carinas distinct. Front very long, narrowest
between the eyes, enlarging below. Antennas long, the first segment
about as long as the second. Tibial spur unusually large. Pronotum
shorter than the vertex, distinctly tricarinate with the lateral carinae
attaining the hind margin. vScutellum about twice the length of pro-
notum, tricarinate.

General color dark brown. Vertex, pronotum and scutellum dark
piceous, whitish along median carina. Front and clypeus dark with
edges of carinee paler. Second antennal segment light brown, first
segment paler. Eyes brown. Elytra subhyaline, nervures prominent,
fuscous. Tergum fuscous with genitalia paler. Legs pale, faintly and
indistinctly lineated with fuscous.

Male pygofer trilobate, lateral lobes curved around behind, ventral
margin of median lobe roundingly emarginate with a large hairy lateral
tooth each side; pygofer pale brown with the drawn out base darker;
genital styles rather short and stout, dark; armature of diaphragm
produced in two long teeth; aedeagus apparently forked.

Length of body 2.75 mm. ; length to tip of elytra, 4 mm.

Described from a single male, taken at light trap at Ocean
Springs, Miss., Aug. 3, 1921, by the author. I do not hesitate
to describe this species from a single specimen as it is quite
distinct.

Type in author's collection.

Stenocranus breviceps sp. nov.

In general appearance of female quite similar to dorsalis
and angustatus but easily distinguished from these and the
other members of the genus by its short and very broad vertex,
the comparatively long elytra, well rounded at the tips and
distinct male genitalia.

Head slightly narrower than prothorax, vertex short, somewhat
rectangular in shape, produced about one-fourth of its length beyond
eyes, strongly carinate. Frons one-third as broad as long, narrowed
above, distinctly carinate. Antennae rather short, second segment

Jan., 1922 synopsis of the genus stenocranus 77

three times as long as first. Pronotum long, proportionateh^ broad;
carinas on account of their whitish color are indistinct, the lateral ones
not attaining the hind margin. Elytra long, narrow, enlarging towards
the apex, well rounded at tips. Legs slender; calcar typical, slender,
pubescence slight.

General color light yellowish-brown to brown. Dorsum with more
or less distinct whitish vitta, continued by the pale commisural nervure
of the closed elytra. Carina? of vertex, front and clypeus whitish with
intra-carinal spaces black. Distal end of basal segment of antennae
with black mark, a similar mark on the cheek below the ocellus. Pro-
notum for the most part of a pale whitish color, a fuscous band bordering
each side of the median white vitta, and fuscous markings at sides of
pro- and mesonotum. Scutellum whitish. In the female the elytra
are of a uniform pale yellowish to brown hyaline, with nervures whitish.
In the male the inner half of the elytra below the commisural nervure
is more deeply enfumed ; the tip of the elytron beginning with the trans-
verse veins is deeply infuscated, forming an almost round apical dark
area within which the nervures are fuscous.

Female ovipositor sheath longer and narrower than in dorsalis,
pale in color, the ovipositor fuscous.

Male pygofer rather long and narrow, with ventral margin deeply
and acutely angled emarginate; genital styles long and slender, stouter
at base.

Length of body, female, 3 mm.; male, 2.5 mm.; length to tip of
elytra, female, 5 mm. ; male 4.25 mm.

Described from a series of ten females and five males taken
by the writer sweeping sedges and marsh vegetation at Moss
Point ferry across Pascagoula River, Pascagoula, Miss.,
Aug. 8, 1921.

Holotype and allotype in author's collection. Paratypes
deposited in U. S. National Museum and collections of the
State Plant Board of Mississippi. Prof. Herbert Osborn and
Z. P. Metcalf.

Stenocranus croceus Van D.
(1902 Bui. Buf. Soc. Nat. Sci., v, p. 233).

Closely allied to dorsalis but very much smaller, of a general
yellowish-orange appearance, and the front is shorter and wider.

Vertex short, produced beyond the eyes about one-third its length,
carinse distinct. Front long, rather broad, narrowing gradually to
base and slightly rounded to clypeus, tricarinate. First antennal seg-
ment one-third as long as second. Pronotum as long as vertex, tri-
carinate, carinae attaining hind margin. Scutellum about twice as long
as pronotum, tricarinate.

78 H. L. DOZIER Vol. XXII, No. 3

General color pale yellowish-orange, although slightly more sordid
in some specimens. Vertex, pronotum and scutellum yellowish-
orange or sordid yellow, with whitish band along median carina. Front
and clypeus yellowish-orange with pale area along each side of median
carina.' Antennae pale. Eyes brown. Elytra subhyaline, nervures,
especially the commissural one, pale. Tergum yellowish-orange.
Legs pale, without markings; tarsal claws piceous; calcar typical, large
and distinctly dentate.

Female ovipositor sheath narrower than in dorsalis, and not
foliaceous; not closely appressed to nor entirely covering the genital
segment; pale orange-yellow with the ovipositor itself darker.

Male genitalia in single specimen on hand obscure. Pygofer fairly
large, ventral margin roundingly emarginate; genital styles quite
different from those of dorsalis, large at base, narrowing only slightly
beyond middle and enlarging distad, with the inner tip pointed.
^ Length of body, 2.50-3 mm. ; length to tip of elytra, 3.75-4.75 mm.

Redescribed from a single mutilated male and a female from
Devil's Lake, N. D., two females from Brookings, S. D., one
female from Delphos, Kan., and two females from Springer,
N. Mex., all collected during July, 1909, by Prof. Herbert
Osborn, and a large series of both sexes from Portland, Maine,
August 13, 1913, H. Osborn.

Stenocranus hinei, sp. nov.

Resembles breviceps superficially but is smaller, the legs
unmarked and the male genitalia quite distinct.

Head slightly narrower than pronotum. Vertex short, produced
beyond the eyes about one-fourth its length, carinas rather indistinct,
especially the median one, which is almost obsolete. Front long and
narrow, narrowing to base, one-third as broad as long, tricarinate.
Antenna with second segment three times as long as the first; seta
fuscous, three times as long as the second segment. Pronotum not
quite as long as the vertex, tricarinate, with the lateral carinse almost
attaining the hind margin. Scutellum tricarinate. Elytra long and
narrow. Legs slender; calcar typical, long and slender.

General color pale yellowish-brown with whitish median vitta, this
vitta accentuated by the fuscous stripes bordering it on the pronotum
and scutellum. Frontal carinas whitish with the spaces between dark
fuscous. Gense dark fuscous next to the lateral carinas of front, whitish
beyond to antennae. Antennae pale, unmarked. Eyes light brown.
Elytra in both sexes pale soiled yellow to hyaline brown with the com-
misural nervure whitish; nervures pale, becoming brown in ante-apical
cells; radio-medial cross-nervure and anteapical nervures at tips,
infuscated. Legs pale, unmarked.

Female ovipositor sheath long, somewhat foliaceous, extending
beyond tip of abdomen, sides subparallel.

Jan., 1922 synopsis of the genus stenocranus 79

Male pygofer medium in size, excavated into a large median spur
and two longer lateral ones ; anal tube with a long, sharp median process
on ventral margin; genital styles rather long, larger at base, narrowing
in middle, much enlarged, retorsed, and cut off distad, very pale in
color; aedeagus of dark fuscous chitin, composed of three parts, the
ventral one rather stout, sharp, and barbed, the middle one thorn-like,
very long and sharp, the upper one short and stout with a pair of curved
hooks at tip.

Length to tip of elytron, male, 4 mm. ; female, 4.75 mm.

The male is similar to the female in coloration and markings, but is
smaller.

Described from a series of nineteen males and fourteen
females, taken sweeping at swamp edge, Los Amates, Guate-
mala, Jan. 17, 1905, by Prof. J. S. Hine, after whom I name
the species.

Holotype and allotype in collection of Prof. Herbert Osborn
as well as those paratypes not otherwise designated. Paratypes
in U. S. National Museum and in the collections of Z. P. Metcalf
and the author.

Stenocranus angiistus Crawford.
(1914 Proc. U. S. Natl. Mus., xlvi, p. 589).

As I have not seen the original type specimen I am including
here the original description.

"Length of body, 3.1 mm.; width of vertex, 0.20; width of frons,
0.22; antennee, I, 0.05; II, 0.22. General color brown or dark
brown, dorstun with conspicuous white vitta; frons black between
carinse; femora striped black; elytra mostly dark brown except outer
anteapical and costal cell and small part of membrane light.

Vertex aboiit as long as in dorsalis, projecting about one-third its
length before eyes, about twice as long as broad; frons one-third as
broad as long, slightly narrowed at ocelli.

Thorax slender; prothorax not much broader than head; scutellum
long. Calcar slender. Elytra long and very slender.

Male genitalia somewhat similar to dorsalis; styles more slender and
delicate, very acute and slender distad.

Described from one male, taken at Belize, British Honduras,
by J. D. Johnson. This species is similar in many respects to
the northern 6". dorsalis.

Type-specimen. — In collection of Pomona College, Cal."

80 H. L. DOZIER Vol. XXII, No. 3

Stenocranus rostrifrons Crawford.
(1914 Proc. U. S. Natl. Mus., xlvi, p. 591, two figs.)

"Length of body, 3.6 mm.; width of vertex, 0.20; length to apex of
head, 0.72; width of frons, 0.21; antennas I, 0.07; II, 0.21. General
color yellowish orange; frons with a slender black stripe near apex
of above; antennas lineated narrowly with black beneath or in front.

Head long, narrower than prothorax, strongly carinate between
eyes, produced almost two-thirds of its length beyond eyes, curved
down somewhat and resembling very closely a bird's beak, acute
at apex; vertex very elongate, narrow, about four times as long as
broad, narrowed anteriorly; median carina almost wanting; frons
elongate, broadest below, not strongly carinate; eyes rather small;
ocelli conspicuous. Antennas not as long as width of head between
antennal sockets, II about three times as long as I.

Thorax slender, long, not strongly carinate; pronotum about two and
a half times as long as scutellum, broadly emarginate behind. Calcar
typical, pubescence slight. Elytra long, strongly attenuate at base,
more rhomboidal apically than in congenors, maculate on membrane
veins; venation somewhat different from that of congenors.

Female ovipositor sheath somewhat broadened, about midway
between foliaceous and cylindrical.

Described from one female from Habana, Cuba (Baker).
Type-specimen. — In collection of Pomona College, Cal."

Stenocranus maculipes Berg.
(1879 Hemipt. Argentina, p. 223).

This species was placed in the genus Delphax by Berg but
without question should be assigned to Stenocranus, at least
until again recognized. I am including here a translation from
the original Latin description:

"Female: Fuscous, here and there variegated with testaceous,
elytra and legs testaceous, the former with fuscous veins, and infuscated
at interior margin, the latter obscurely spotted and banded with fuscous;
hind part of head narrower than pronotum, produced beyond the eyes;
vertex longer by half than its basal width, somewhat narrowed upwards,
margins strongly elevated, median carina lacking, the two lateral caringe
meeting at an acute point; frons and clypeus tricarinate, the former
scarcely curving on both sides before the middle, then very slightly
widened towards apex, banded with white in front of the middle and at
apex; clypeus white at base; first antennal segment somewhat com-
pressed, second somewhat longer and more slender, the latter strongly
tuberculate, above and below a little dilated; pro- and mesonotum
obscurely fuscous, tricarinate, the former widened behind, carinse
distinct, rather pale, the latter with lateral carinse somewhat obsolete,

Jan., 1922 synopsis of the genus stenocranus 81

median carina extended all the way to apex of scutellum; elytra much
longer than abdomen, subhyaline, all veins and the interior margin
partly inf uscate ; wings hyaline ; dorsum and venter of abdomen fuscous ;
greater part of femora blackish-brown, tibiae with two blackish bands,
hind ones bispinose in front of the middle; tarsi light yellowish, partly
fuscous. Length of body, 4>^ mm. ; elytra, 4>^; width of meson, 1 mm.
"Country: Province of Buenos Ayres."

Of this species I received from Sr. Ed. Lynch Arribalzaga,
one individual that was collected in Rio Lujan during the
month of February, 1879.

A comparative study of the male genitalia of the members
of this genus show that dorsalis, vittatus, felti, angustus, similis,
and croceus are very closely related to each other. PalcBtus
and longicornis on the other hand form an entirely distinct type
of development with the py gofer more or less trilobate. Breviceps
shows a third type in which the ventral margin of the pygofer
is deeply and angularly emarginate. Hinei is the sole repre-
sentative of a fourth type having the pygofer formed of a
median and two lateral large teeth and with a single median
anal process. Rostrifrons is known from a single female and
therefore no comparison can be made of the male genitalia.

The relation of these species to one another as shown in a
study of the genitalia is borne out by the external structure.

The Genus Mysidia Westwood.

Many of the members of this genus closely resemble certain
small whitish Geometrid moths. They run very swiftly on the
upper surface of leaves or when caught in a net, with their wings
partially raised. The genus is tropical, at least nine species
occurring in Central America and nothing is known of their
life-history. Heretofore no species has been known from North
America.

For the most part members of this genus are of a white more
or less opaque color; the head is narrow and compressed; the
antennae have the first joint short, the second large and swollen,
more or less pointed or truncate, the third consisting of a fine
seta ; the tegmina are very long and rather narrow, much larger
than the wings, both vitreous, with the veins very light in color
with occasional more or less obscure markings. One of the
best characteristics of the genus is the large number of long,
narrow, and very regular apical areas.

82

H. L. DOZIER

Vol. XXII, No. 3

Mysidia mississippiensis , sp. nov.

Technical description. — Head, antennas, pronotiim and scutellum
yellowish, covered more or less with whitish powder, abdomen with
greenish tinge; abdominal plates meet in a median ridge; head very-
narrow, compressed, distinctly produced before the eyes and plainly
longer than the pronotimi; eyes dark brown; pronotum narrow with
sides flaring-like. Tegmina and wings translucent, of a milky-white
color, venation distinctly but not strongly marked; tegmina long and
rather narrow, with very light fuscous areas especially along the trans-
verse veins and a distinct fuscous patch near middle of the posterior
margin of tegmina. Legs very slender, testaceous.

Length of body, male, 2.50 mm.; female, 3 mm.; wing expansion,
male, 15 mm.; female, 17 mm.

Fig. 2. Mysidia mississippiensis

Described from a single female taken by the writer sweeping
Arundinaria and grass in Oktibbee Swamp near Meridian,
Miss., Aug. 14, 1921, and a series of two females and a male
taken in a swamp near Leland, Miss., Sept. 15, 1921, by C. J.
Drake.

Type in the author's collection. Paratypes deposited in
collections of Prof. Herbert Osborn, Z. P. Metcalf, and the
State Plant Board of Mississippi.

A Synopsis of the Genus Stenocranus
H. L. Dozier

Plate I

dor sails
H. L. Dozier, del,

Si mills

THE HOMOLOGIES OF THE TRACHEAL BRANCHES
IN THE RESPIRATORY SYSTEM OF INSECTS

CLARENCE HAMILTON KENNEDY
Department of Zoology and Entomology, Ohio State University

The following study of the tracheation of the Zygoptera
was undertaken to determine the homologies of the tracheal
branches that supply parts of the genitalia of the second and
third segments of the male. This full investigation will eventu-
ally appear in one of the government publications but the study
brought to light points of so much greater importance that a
discussion of these was given at the Toronto Meetings of which
this article is the outline.

Grassi* has shown the probability that the insect tracheal
system was originally a series of disconnected segmental sys-
tems which later fused into a connected whole.

Chapmanf has homologized the main thoracic tracheae
which form the main air supply of the wings in the various
orders of insects, and has shown us that the tracheal system
can be homologized but so far no attempt has been made to
refer these back to the more generalized (?) plan found in the
tracheation of the abdominal segments. In the majority of the
general morphological works on insects the tracheal system is
described as being composed of certain longitudinal trunks
with various accessory parts in the way of spiracles, air sacs,
cross-connections, etc. This is true, but these are not descrip-
tions which take into consideration the origin and homologies
of the individual parts of the tracheal system.

The Zygopterous naiad, among the nymphs, of all winged
insects, appears to have the abdominal segments least modified
from a probable primitive condition. Its abdomen is clyindrical,
therefore no parts are displaced or lost by depression. Its gills
are at the apex of the abdomen, therefore their position does
not modify any but the caudal parts of the system. The abdo-
men is elongate so that each segment can be studied individually.

* Atti dell' Accad. Groenia d. Sci. Nat. Catania (3) T. XIX. 1885.
t In "Wings of Insects," Comstock, pp. 27-51.

84

Jan., 1922 the tracheal branches of insects 85

The nymph of Lestes, which furnished the material for this
study, is so abundant and so transparent that little dissection
was needed.

In this article the writer will outline the homologies of the
principal thoracic tracheal branches as referred back to the
simpler system of an individual abdominal segment. The terms
used are descriptive as far as possible and were worked out
with the help of Dr. Chapman with the hope that we had terms
that would be useful in future tracheal studies.

If the reader will refer to the plate he will see in Fig. 1 the
simplest tracheal unit in abdominal segment 2. It is repeated
in segments 3-7. Segments 1 and 8-10 have more or less mod-
ified versions of this same unit. In the thorax the tracheal
branches are yet more highly modified. The diagram Fig. 3,
shows what the writer considers as the hypothetical primitive
unit from which the present system with its longitudinal trunks
has been developed.

The studies of the primitive tracheal systems in Peripatus
and in the embryology of the insectean tracheal system show
that the spiracles develop first as pits. From the bases of these
pits the tracheal branches develop. Our unit starts then with
(1) the spiracle, sp., extending into the body wall, (2) is the
spiracular pit, spp. From the bottom of this there develops
dorsad a short stout branch, (3) the spiracular trunk, spt.
This trunk forks and sends a branch, (4) the anterior dorsal
connective, adc. to the muscles of the anterior end of the seg-
ment, and a branch (5) the posterior dorsal connective, pdc. to
the posterior muscles of the dorsum of the segment. Each of
these has a branched tip supplying its group of muscles, (6) (7)
the tip of the anterior dorsal connective, tadc, and the tip of
the posterior dorsal connective, tpdc. These tips become land-
marks later in the study.

The spiracular pit sends out three other branches, (8) the
■anterior spiracular connective, asc, which connects forward to
the leg trachea and which gives off a small branch to the body
wall, (9) the posterior latero-tergal trachea, pit. Opposite to this
(8) is given ofif a larger trachea, (10) the leg trachea. It, which
runs caudad and ventrad. It gives off first, (11) the anterior
latero-tergal trachea, alt, to the body wall, then (12) the pleural
trachea, pt, to the pleural fold. Ventrad the spiracular pit gives

86 CLARENCE HAMILTON KENNEDY Vol. XXII, No. 3

off a slender branch direct to the gangHon of the segment
(13) the ganglionic trachea, gt. This has a tip which runs along
the sternum caudad from the ganglion, (14) the sternal trachea, st.

As this hypothetical unit is derived from the tracheal
system as it appears in the less modified abdominal segments
these terms are directly applicable to the parts in Fig. 1. In
this figure it will be seen that the anterior and posterior dorsal
connective have united as they alternate along the dorsum into
a large dorsal trunk. In Lestes it is especially large as it functions
with its mate of the opposite side, as a swim bladder, while
along it at regular intervals are the tips of the anterior and
posterior dorsal connectives.

In the front end of the abdomen the ganglions of segments
1 and 2 have each moved cephalad one segment. In each case
the ganglionic trachea has followed its ganglion cephalad. The
ganglion of segment 1 fuses with that of the metathorax but the
elements of the tracheal supply are still recognizable. See
Fig. 2, which is a ventral view of the thorax.

In each segment the anterior spiracular connective has fused
with the leg trachea next ahead so that in the abdomen there
is a delicate but complete lateral trunk. In the thorax a pair
of ventral or sternal trunks appear by the fusion of the sternal
trachece with each succeeding ganglionic trachea. This fusion is
not completed in the abdomen. See Fig. 2.

In the thorax but two spiracles persist, the mesothoracic
and the metathoracic. Of the prothoracic spiracle, some of the
tracheal branches are present which would be expected with it
but the spiracle itself has left no recognizable trace. The
tracheal system of the metathorax is least modified. Here the
spiracular trunk is still fully developed. In the mesothorax the
spiracle has moved dorsad until the spiracular trunk, st, has
been obliterated. It is also entirely lost for the prothorax.

The modification of the thorax due to the development of
the wings has profoundly changed the proportions of the other
thoracic branches also. In a later paper the writer will trace
this change from the first instar where it is very similar to the
abdominal tracheal system through its development to the
extreme modification shown in Fig. 1 which is a tenth instar
naiad.

The wings start as simple pleural folds no wise different
from those of the abdomen. By the fourth instar those of the

Jan., 1922 the tracheal branches of insects 87

thorax have moved dorsad and those of the mesothorax and
metathorax have begun to take on the place and shape of wing
pads. The simple pleural trachea, pt, tracheates them in the
beginning and follows them as they pass from the lateral to
their final dorsal position. The pleural trachea is the anterior
or costal wing supply and is the original wing supply as this
devlopment shows. As the wing folds (later, pads) pass dorsad
they pass the tips of an anterior and di posterior dorsal connectives
in each segment and take on connections with these. Also the
anal apex of each wing trachea {pleural trachea) connects also
with the anterior latero-tergdl trachea of the succeeding segment.
Thus each wing in Lestes has four tracheal connections.

Several puzzling shifts and specializations have taken place.
In segment 1 the leg branch is lost and the anterior spiracular
connective has shifted from the spiracle down onto the gangli-
onic trachea. This has occurred also in the second and third
thoracic segments so that the posterior latero-tergal trachea in
each case has shifted to arise from near the spiracle.

In the metathorax the metathoracic tip of the posterior dorsal
connective has shifted down onto the vertical spiracular trunk.
This conclusion is arrived at by elimination of the other tips.
This solution homologizes the tracheation of the hind wing with
the tracheation of the front wing.

In the thorax the ganglionic trachea have shifted down onto
the leg trachea in each segment, and in each segment a second
or accessory ganglionic trachea, agt, has appeared.

The shortening of the spiracular trunk in the mesothorax
has pulled the leg trachea of the prothorax out of shape and has
greatly shortened the anterior spiracular connective of the
mesothoracic spiracle so that the lateral trunk becomes a
second dorsal trunk in the insect's neck.

This work in tracheation is very much confused by mal-
formations and adventitious branches. Frequently there are
two or even three anterior or posterior latero-tergal trachece,
sometimes two pleural trachece, etc. One has to examine enough
specimens that these abnormalities are recognized as such and
no longer confuse. This readiness of the tracheal system to
develop new branches has been one of the things which has
made homologization of the branches seem a hopeless task.

The tracheation of the internal organs seems to be largely
fortuitous except for two large trachea that run from the

88 CLARENCE HAMILTON KENNEDY Vol. XXII, No. 3

metathoracic spiracular trunks to the region of the gut just back
of the gizzard and two others that run from the spiracular
trunks in abdominal segment 8 to the region of the intestine
just back of the malpighian tubules. The tracheation of the
head is very definite but so far has not been homologized with
the parts of the system in the thorax and abdomen unless the
tracheas of the labium can be homologized with leg trachece.

This study supports the theory that the wings are developed
from pleural folds as this feature can be positively homologized
from the larval pleural fold stage to the adult winged stage.

The only other order the writer has examined is the Plecop-
tera. Here the tracheal system is greatly distorted by the
thoracic gills and the depressed body. A pair of neural trunks
are formed in the abdomen by the fusion of the sternal trachece.
A lateral abdominal trunk is well developed which is probably
homologous with the lateral trunk of the Zygoptera though
this may be found to be homologous with the dorsal trunk of
the Zygoptera. The thoracic trachea are less changed.

The writer believes that this reference of the tracheal
branches back to those in a generalized abdominal segment
will give a solution to the homolgies of the tracheal systems in
the various orders of insects. He hopes soon to carry the
study farther.

Jan., 1922 the tracheal branches of insects 89

EXPLANATION OF PLATE.

Fig. 1. Lateral view of Lestes naiad, male, showing the homologies of the somatic
tracheal branches.

Fig. 2. Ventral view of Lestes naiad.

Fig. 3. Hypothetical, primitive segmental tracheal organs. By the fusion of
a series of such the Lestes trachial system may have been developed.

LIST OF ABBREVIATIONS USED IN THE ILLUSTRATIONS.

sp. — spiracle.

spp. — spiracular pit.

spt. — spiracular tnmk.

St. — sternal trachea.

dt. — dorsal trunk.

latt. — lateral trunk.

vt. — ventral trunk.

It. — leg trachea.

pt. — pleural trachea.

gt. — ganglionic trachea.

agt. — accessory ganglionic trachea.

asc. — anterior spiracular connective.

adc. — anterior dorsal connective.

pdc. — posterior dorsal connective.

alt. — anterior latero-tergal trachea.

pit. — posterior latero-tergal trachea.

tadc. — tip of anterior dorsal connective.

tpdc. — tip of posterior dorsal connective.

The Tracheal Branches of Insects
Clarence H. Kennedy

Plate I

Clarence H. Kennedy

ADDITIONS TO THE CATALOG OF OHIO VASCULAR
PLANTS FOR 1921.*

JOHN H. SCHAFFNER

Department of Botany, Ohio State University

During the past year a number of additions have been made
to the Ohio flora and some important extensions of ranges have
been detected. Below is given a Hst of the more important
additions, with some corrections of species names.

54. Equisetumfluviatile'L. Swamp Horsetail. Cedar Swamp,
south of Urbana, Champaign Co. John H. Schaffner.

71. Piniis echinata Mill. Shortleaf Yellow Pine. Jackson

Twp., Jackson Co., Wilkesville and Vinton Twps.,
Vinton Co. "This pine is generally distributed over
N. E. Jackson County, and is the dominant pine
with scrub and pitch pines. Its occurrence, however,
in Vinton County is rather limited and restricted,
occurring always on the ridges." F ,W. Dean.

72. Thuja occidentalis L. Arborvitae. On east bank of

Brush creek, Bratton Twp., Adams Co. Katie M.
Roads.

236. Carex platyphylla Car. Broadleaf Sedge. Hillsboro,
Highland Co. Katie M. Roads.

384. Sporoboliis vaginaefloriis (Torr.) Wood. Sheathed Rush-
grass. Hillsboro, Highland Co, Katie M. Roads.

414. Change name to Torresia odorata (L.) Hitchc. instead of
Savastana odorata (L.) Scvih. Add: Specimens from
Blanchester, Clinton Co. "Wet meadows." E. Lucy
Braun.

545. Juncus torreyi Cov. Torrey's Rush. Hillsboro, High-
land Co. Katie M. Roads.

552.1. Juncoides bulbosiim (Wood) Small. Bulb-bearing Wood-
rush. Blanchester, Clinton Co. "Wet meadows."
E. Lucy Braun.

567. Fissipes acaidis (Ait.) Small. Moccasin-flower. Iron-
ton, Lawrence Co. Lillian E. Humphrey.

* Papers from the Department of Botany, Ohio State University. No. 132.

91

92 JOHN H. SCHAFFNER Vol. XXII, No. 3

662. Sarracenia purpurea L. Pitcher-plant. Cranberry

Island, Buckeye Lake, Licking Co. Spreading abun-
dantly from a single plant set out several years ago
by Miss Freda Detmers. Hundreds of vigorous
plants now cover a considerable area of the open
Sphagnum bog. John H. Schaffner.

663. Drosera rotiindifolia L. Roundleaf Sundew. Cedar

Swamp, southern part of Clarke Co. Mrs. Bayard

Taylor.
683. Koniga maritima (L.) R. Br. Sweet Alyssum. "Per-
sistent and an escape from cultivation." Hillsboro,

Highland Co. Katie M. Roads.
706. Sophia pinnata. (Walt.) Howell. Pinnate Tanzy-

mustard. Gravel slide, Huffman Dam, Greene Co.

Also in Clark Co. A. E. Waller.
714. Conringia orientalis (L.) Dum. Hare's-ear-mustard.

Hillsboro, Highland Co. Katie M. Roads.
739. Dentaria diphylla Mx. Two-leaf Toothwort. Near

Hillsboro, Highland Co. Katie M. Roads.
744. Sinapis arvensis L. Corn Mustard. " In waste places

and gardens." Hillsboro, Highland Co. Katie M.

Roads.
746. Brassica jiincea (L.) Cosson. Indian Mustard. Hills-
boro, Highland Co. Katie M. Roads.
805.1. Tithymalus falcatus (L.) Kl. & Garke. Native of

Europe. Along railroad between Fairmount and

Westwood, near Cincinnati, Hamilton Co. Louis H.

Desjardins.
925. Dianthus armeria L. Deptford Pink. "In a pasture

lot." Hillsboro, Highland Co. Katie M. Roads.
1009. Potentilla recta L. Upright Cinquefoil. Roadside near

Bainbridge, Ross Co. A. E. Waller.
1286. Almis incana {L,.)y^\\\6.. Hoary Alder. Cedar Swamp,

south of Urbana, Champaign Co. John H. Schaffner.
1323.1. Opuntia tort i spiv a Engelm. Twisted-spine Prickly-pear.

In large patches in gravel soil in railroad cut. Terrace

Park, Cincinnati, Hamilton Co. From the west. E.

Lucy Braun,
1420. Phlox pilosa L. Downy Phlox. "In pine woods."

Ironton, Lawrence Co. Lillian E. Humphrey.

Jan., 1922 omo vascular plants for 1021 93

1434. Convolvulus japonicus Thunb. Japanese Bindweed.

Escaped along a road near Brooks, Clark Co. John

H. Schajffner.
1465. Gentiana crmita Froel. Fringed Gentian. "In a swamp"

near Canton, Stark Co. Mary King.
1471. Frasera carolinensis Walt. American Columbo. Blen-

don and Pleasant Twps., Franklin Co. John H.

Schaffner.
1526.1. Paidownia tomentosa (Thunb.) Baill. Paulownia.

Escaped in Ironton, Lawrence Co. Lillian E.

Humphrey.
1529. Conobea muUifida (Mx.) Benth. Conobea. Hillsboro,

Highland Co. Katie M. Roads.

The following changes of names should be made in the
family Scrophulariaceae, to agree with the treatment of the
Ohio species by Mary A. Taylor in "The Figworts of Ohio,"
Ohio Jour. Sci. 21:217-239, 1921. The sequence of genera and
species should also follow the arrangement given there.

1530. Gratiola neglecta Torr. instead of Gratiola virginiana L.

1531. Gratiola virginiana L., instead of Gratiola sphaero-

carpa Ell.
1547. Veronicastrum virginicum (L.) Farw. instead of Lep-
tandra virginica (L.) Nutt.

1551. Dasistoma macrophylla (Nutt.) Raf. instead of Afzelia

macrophylla (Nutt.) Ktz.

1552. Aureolaria pedicularia (L.) Raf. instead of Dasystoma

pedicularia (L.) Benth.

1553. Aureolaria virginica (L.) Pennell, instead of Dasystoma

flava (L.) Wood.

1554. Aureolaria laevigata (Raf.) Raf., instead of Dasystoma

laevigata Raf.

1555. Aureolaria flava (L.) Farw. instead of Dasystoma

virginica (L.) Britt.

1686. Salvia lyrata L. Lyreleaf Sage. Paint Twp., Highland

Co. Katie M. Roads.
1695a. Plantago aristata nuttallii (Rapn.) Morris. A peculiar

but probably merely a depauperate form of P. aristata.

Gallipolis, Gallia Co. R. H. Martin.

94 JOHN H. SCHAFPNER Vol. XXII, No. 3

1761. Galium pilosum Ait. Hairy Bedstraw. Paint Twp.,
Highland Co. Katie M. Roads.

1777. Viburnum defitaium L. Toothed Arrow-wood. "Wet

meadows and undrained flats. " Martinsville, Clinton
Co. E. Lucy Braun.

1778. Viburnum scabrellum (T. & G.) Chapm. Roughleaf

Arrow-wood. Union Twp., Highland Co. Katie M.
Roads.

1786.1. Triostium aurantiacum Bickn. Scarlet-fruited Horse-
gentian. Toboso, Licking Co. E. N. Transeau.

1794. Lonicera japonica Thunh. Japanese Honeysuckle. " Col-
lected on the bank of a small pond." Hillsboro,
Highland Co. Katie M. Roads.

1873. Bidens aristosa (Mx.) Britt. Western Tickseed. Bratten
Twp., Adams Co. Katie M. Roads.

1948. Aster junceus Ait. Rush Aster. "Wet meadows."
Midland, Clinton Co. E. Lucy Braun.

1952. Aster midtiflorus Ait. Dense-flowered Aster. Omit
Gallia Co. from distribution.

1964.1. Leptilon divaricatum (Mx.) Raf. Low Horseweed. "Dry
sandy soil, roadside." From the west. Winton
Place, Cincinnati, Hamilton Co. E. Lucy Braun,

2005.1. Artemisia ludoviciana Nutt. Western Mugwort. Estab-
lished along the interurban track near Brooks, Clark
Co. From the west. John H. Schaffner.

2030.1. Centaurea solstitialis L. Barnaby's Star-thistle. Arch-
bold, Fulton Co. In alfalfa field introduced with
alfalfa seed. John S. Nofzinger! Also at Lima,
Allen Co. L. S. Van Natta.

NOTES ON THE FOOD HABITS OF YOUNG
OF COTTUS ICTALOPS (Millers Thumb.)

C. L. TURNER

Zoological Laboratory, Beloit College

While the writer was engaged in collecting the fry of the
Perch and of the Darters in the vicinity of Put-in-Bay, pre-
paratory to making a study of their food habits a locality was
found in which the young of Cottus ictalops were fairly
abundant.

Around the shores of Buckeye Island there is an abundance
of short, thick vegetation, shaded by willows and protected
and held together by willow roots. This margin is constantly
awash due to the exposed position of the island. The young of
Cottus ictalops and of the Fan Tailed Darter {Etheostoma
flabellare) were found hiding in the vegetation and under the
rocks in the vicinity. It was not possible to take the fish in a
seine because they were* so well protected but a small collection
was secured by persistently dragging the vegetation with a fiat
ended dip net.

About a hundred specimens were taken ranging in size from
12 to 22 millimeters and the stomach contents of thirty-five
were examined. The food articles have been arranged in a
tabular form showing the proportion of each kind of food eaten
by each size of fish.

Although ten different articles occur in the food some of
them are almost negligible in quantity and even the youngest
fish seem to prefer large, active Amphipods or insect larvee. In
some cases a single insect larva, two-thirds as long as the fish
filled the stomach.

The young of most fish subsist on Entomostraca during the
younger stages, turning later to specialized and larger foods.
In a fish of generalized feeding habits the time during which it
takes Entomostraca is known as the period of infancy, a later
period when midge larvae and other minute insect larvae are
used is known as the period of youth, while the stage in which
the usual food of the adult is taken is designated as the period
of maturity. The period of infancy seems to be entirely omitted

95

96

C. L. TURNER

Vol. XXII, No. 3

or to be passed over in specimens of less than 12 millimeters in
length. In this regard it resembles Etheostoma flabellare,
which unlike most of the other darters captures large, active
food while still very small and if it takes Entomostraca at all it
does so only in negligible quantities.

The adult Millers Thumb is reported to be a voracious
feeder and very destructive to other fish. It is interesting that
the young resemble the adult in their ability and their willing-
ness to capture large food animals which are proportionately
large even in 12 millimeter specimens. It is well adapted to
feeding upon large objects by its large terminal mouth.

Table illustrating the food of young of Coitus ictalops.

Length in mm.

12

13

14

15

16

17

18

19

20

21

22

No. examined

1

1

1

2

3

5

5

5

5

4

3

Articles of diet:
Midge larvae

100.

100.

2.5

33.33+

22.6

20.

22.5

28.75

1.66+

May fly larvae

60.

51.66+

43.8

54.

25.

32.5

75.

81.66+

Amphipods

47.5

15.

27.4

18.

52.5

12.5

12.5

Fish remains

40.

6.

20.

12.5

Bottom debris

5.

Beetle larvae

48.5

16.66+

Round worms

1.2

Filamentous algae

1.

Fish eggs

1.5

4.

2.

Insect eggs

1.25

Figures represent the percentage of the volume of the stomach contents.

CONCRETIONS IN LAKE DEPOSITS
AT ELYRIA, OHIO

GEORGE D. HUBBARD
Department of Geology, Oberlin College

Excavations near the corner of Middle Avenue and Sixth
Street, Elyria, made preparatory to the erection of heating
plant extensions for the school buildings located there, have
brought to light some calcareous sand and clay concretions in
the making.

The pit is twelve or fourteen feet in depth. The section is
as follows:

4. Filling, artificial, (clay, brick-bats, crockery, etc.), 2 ft.

3. Brown to yellow sands and clays 8 ft.

2. Blue and blue-gray clays 2 ft.

1. Blue sands 1-2 ft.

Layer number one is micaceous sand and in parts argilla-
ceous. It gives under the weight of horses and wagon and
behaves much like quicksands. It seems to be full of water,
but the water is not flowing through. Layer number two is
dryer and is variable in thickness, the upper surface being
quite uneven. In places the layers above seem to be pushed
into it. In other parts a yellow stain seems to have penetrated
the blue clays from some point or line of seepage, in concentric
spheres or layers. Thus the yellow above and the blue below
are mutually interpenetrating and uneven. It is along this
uneven contact that the concretions occur. The circulating
water responsible for the concretions seems to be moving
through layer three and descending to number two.

Some of the concretions are small and of indefinite bound-
aries and shapes, some are larger and resemble in shape lemons,
cocoanuts and even vases a foot high, with a diameter of three
or four inches. Most concretions have a nucleus of some sort.
In many of these there seems to be a twig or branch of wood, a
quarter of an inch to an inch in diameter, which reaches the
whole length of the structure. In most cases, this twig retains
some of its woody structure and fiber. The clay and sand

97

98 GEORGE D. HUBBARD Vol. XXII, No. 3

surround the stem and the cementing has been done in con-
centric shells. Layers are thicker in the central part, which
fact makes the concretion thicker in its equatorial zone. Only-
partial cementing has yet been effected, and acid tests indicate
that the cement is calcium carbonate.

All the concretions were yellow or brown, although embedded
in the blue clays. It is obvious that oxidized iron from the
upper layers is penetrating the blue with the calcium carbonate
and that both are being deposited, thus solidifying the clay and
sand of the concretions. Yet the structure is still soft and
can be easily cut with the finger nail. We have here a number
of concretion shapes still in the process of making.

A few hundred yards north or down the slope lakeward
from this deposit is the shore line of Lake Whittlesey, a
precursor of the present Lake Erie; and some three miles south
is the abandoned beach of the Maumee stage. This latter
beach is known east of Elyria as Butternut Ridge, and the
former is now occupied through the business section of town
by Main Street. The clays and sands then are between the
Maumee and Whittlesey beaches and therefore belong to the
Maumee Lake stage. While Maumee Lake was held in on the
north and east by ice and overflowed through the Fort Wayne,
Indiana, outlet, its waves and currents built the Maumee beach
around the Elyria embayment, and on its floor were laid the
clays and sands found in the excavation. Hence the con-
cretions can be correlated with the Maumee Lake stage and
can be shown to be wholly post-glacial. Concretions have
been completed in a time period equal to this, but those found
at Elyria seem to be still in the process of growth and
cementation.

PRESERVATION OF NATURAL CONDITIONS.

E. LUCY BRAUN

University of Cincinnati

The Ecological Society of America desires to publish a
National and International list of areas suitable for biological
study in North America and northern South America. All
preserved areas in natural or semi-natural condition, such as
forest preserves and bird and game sanctuaries; and all other
areas in a natural state, even though they may not be preserved,
should be included. It is hoped that the inclusion of tracts
doomed to exploitation, but still in a natural state, will stimulate
interest and lead to the selection of areas in regions where as
yet there has seemed to be no interest in preservation.

Each area is to be described briefly. The description
should include the following points, so far as possible :

(1) A statement as to the nature of vegetation — forest
(and type), prairie, swamp, sand dune, etc. — and
principal trees or other plants. If succession is well
illustrated, this should be stated.

(2) The animals, including birds and fish, should be noted.

(3) The topography of the area — level, rolling, sharp,
precipitous, dissected — and the altitude (highest and
lowest points, or average for level areas) should be
stated.

(4) If streams or lakes are present, describe briefly, as to
current, depth, width, nature of bottom, purity, etc.,
and animal life.

(5) Locate area, and give directions for reaching it, with
name of transportation company, and distance and
direction from some easily located point or points.
Give desirable means of reaching the area; on foot, by
automobile, horseback. Name nearest post office and
nearest town at which through trains stop.

(6) Give name of nearest town with hotel accommodations ;
or if camp outfit is desirable or necessary.

(7) Any reference to literature dealing with the areas
described should be included.

99

100 B. LUCY BRAUN Vol. XXII, No. 3

(8) If the area is a preserve, state agency which owns, and
controls and manages the preserve. (A preserved area
is one publicly owned or owned by an incorporated
institution) .

The work of collecting the information about natural areas
and preserves has been apportioned by states. In addition
to the description of areas, information is wanted about other
features of natural interest in each state.

(1) Caves: Name, location, approximate size (if known),
geological formation.

(2) Location of unpolluted waters.

(3) Description of lake coast areas still in a natural
condition.

(4) References to literature.

If you know of any preserve or natural area in Ohio (or
elsewhere) which should be included, describe it. Do not fail
to describe areas because you think it has already been done;
additional data will invariably be added where descriptions
are duplicated by different persons.

Do your share in helping to make that part of the
"NaturaHst's Guide" dealing with Ohio as complete as possible,
by sending information as outlined above.

The Ohio Journal of Science

Vol. XXII February, 1922 No. 4

PROGRESSION OF SEXUAL EVOLUTION IN THE
PLANT KINGDOM*

JOHN H. SCHAFFNER

Department of Botany, Ohio State University

Sexuality may manifest itself in at least three diifferent
ways: First, by the property of attraction and fusion of cells;
second, by the dimorphism of characters expressed through the
influence of the sexual state at the time of cell differentiation;
and third, by a difference in the nature of the chemical bodies
produced in cells in different sexual states. In the evolution
of sex there are, apparently, degrees of intensity of the sexual
state and degrees of persistency of any state established for the
time, whether male, female, or neutral. The main factor in the
evolution of sexual dimorphism has been the shifting of the time
in the ontogeny when sexual states arise from the neutral state
or when one sexual state gives place to another. The time of
sex determination ranges all the way from a late stage of
gametogenesis in the lowest forms backward through the onto-
genetic history until, as in diecious flowering plants of the
extreme type, the sexual state of both the sporophyte and
gametophyte is established at the time of fertilization of the
egg or even before. Of course, it must be remembered that
new hereditary factors are continually arising or old ones being
modified, in the upward progression of evolution, which come
to expression either in the presence of one sexual state or the
other or in the presence of both sexual states but with different
morphological values. In either case the dimorphism of sec-
ondary sexual characters becomes more pronounced or more
complex.

* Papers from the Department of Botany, The Ohio State University. No. 133.

101

102 JOHN H. SCHAFFNER Vol. XXII, No. 4

If sexuality is a pltysiological state of the cells, then it
becomes evident that sex reversal might take place at any
time and in any cell or tissue. A neutral condition may change
to a male state or to a female state, or one sexual state may
give place to the other, or a sexual state may revert to a
neutral state again. Such reversals not only take place nat-
urally in hermaphroditic, bisporangiate, monecious and mono-
sporangiate individuals, but they can be induced in various
ways by artificial means in diecious sporophytes, as has been
done by the writer and others in Cannabis saliva, Hitmidus
japonicus, Ariscema triphyllum, and Ariscema dracontiiim.

If a distinction is to be made between different categories
of sexual characters, then in order to avoid confusion of ideas
and improper deductions, the terms "primary" and "sec-
ondary" need a more exact definition for application in genetics
than they have received heretofore.

The proper place to draw the line is between gametes on the
one hand and all other cells on the other. The ordinary dimor-
phic characters are produced because of the presence of a sexual
state and not because of differences in heredity of the cells
involved. A primary sexual character is, therefore, defined as
any sexual character possessed by a gamete. A secondary
sexual character is any sexual character possessed by any cell,
tissue, or organ other than a gamete. Thus the wall cells and
stalks of spermaries and ovaries may show secondary sexual
characters comparable to those of cells farther away in the
vegetative body. The main differences in primary sexual
characters pertain to the size and shape of the gametes, size of
or presence and absence of flagella, differences in activity, dif-
ferences in food contents, and differences in color. The funda-
mental differences exhibited between eggs and sperms are
often quite uniform throughout a class or phylum, while "sec-
ondary sexual characters may be quite diverse.

The lowest plants are apparently devoid of sexual states
during their entire life cycle, and the first indications of sex
are entirely physiological. Passing on from this condition of a
physiological state, the first appearance of a structural difference
or dimorphism appears in the gametes. These differences soon
reach a general, normal, dimorphic condition in the Gonidi-
ophyta with well-differentiated eggs and sperms. So long as
organisms are unicellular they cannot be described as her-

Feb., 1922 sexual evolution in the plant kingdom 103

maphrodites. They must be either male or female although
they may be vegetative sister cells. So soon as a multicellular
condition is attained hermaphroditic individuals are possible,
and in the lower multicellular forms hermaphroditism is the
usual condition. If a progeny of unicellular individuals coming
from an ancestral cell by vegetative growth develops some as
male cells and some as female, we evidently have a condition
essentially like an ordinary multicellular hermaphrodite; for
if the cells remained associated after division instead of splitting
apart the combined units going into the sexual state at a certain
stage of their life history would represent genetical conditions
identical to a multicellular hermaphrodite. The further evolu-
tion from hermaphrodites is by gradual steps to unisexual,
multicellular individuals. In the higher plants with an anti-
thetic alternation of generations, the sporophyte is in the lower
levels entirely neutral and homosporous, showing no sexual
states; and from this condition the higher bisporangiate type
with heterospory is evolved. The heterosporous sporophytes
of the lowest types have bisporangiate leaves or bisporangiate
floral axes. This is the general condition from which both
monecious and diecious species are derived. In the mone-
cious individual the entire floral axis is monosporangiate or the
entire inflorescence, while in the extreme diecious condition the
entire individual produces but one kind of spores, or in other
words has but one kind of sexual expression. The highest
plants, therefore, have unisexual, dimorphic gametophytes and
diecious, dimorphic sporophytes.

The detailed description of these evolutionary series is given
in outline below although no attempt has been made to catalog
the numerous intermediate and special cases.

I. NONSEXUAL STAGE.

1. The organization of the protoplast is apparently such
that the origin of sexual states or phases is impossible. This
may be true both morphologically and chemically. No sexual
state is shown at any stage of the life cycle although there is
considerable evolution and morphological differentiation dis-
played by the highest species of this type of plants.

Apparent examples: Merismopedia, Micrococcus, Anki-
strodesmus, Rivularia.

104 JOHN H. SCHAFFNER Vol. XXII, No. 4

II. LOWER SEXUAL SERIES, WITH REDUCTION OF THE
CHROMOSOMES EITHER IN THE ZYGOTE, OR AT THE
END OF THE SEXUAL GENERATION JUST BEFORE
GAMETOGENESIS.

2. The lowest sexual condition in which sexuality manifests
itself by the development of a passing state of attraction
between two morphologically similar mature cells or isogametes.
In the most primitive cases there is no apparent morphological
or physiological differentiation outside of the property of
attraction.

Examples: Diatoms, Desmids, Sphasrella, Botrydium, Cla-
dophora, Ulothrix, Ectocarpus.

Note: We may assume that there is a chemical or physical,
or perhaps it would be better to say a physiological difference
corresponding to female and male states.

3. Development of a difference in size and sometimes color
of the gametes which in typical cases are ciliated, free-swimming
cells.

Examples: Pandorina, Bryopsis, Codium, Spirogyra sp.
Note : Spirogyra shows a considerable degree of heterogamy
in its highest species.

4. The stage of sexual evolution in which the gametes are
typically difl'erentiated as male and female with a decided
dimorphism, the sperm cell being ciliated and small with little
cytoplasm and food supply and actively motile after being dis-
charged from the gametangium, the egg cell being nonciliated
and comparatively large with abundant cytoplasm and food
supply and also discharged from the gametangium although
nonmotile.

Example: Fucus evanescens.

Note: Fucus also shows a dimorphism of the gametangia,
and belongs to a more advanced stage of sexual evolution, but
its female gametes represent a condition which is just a stage
below the final evolutionary development of sexual cells.

5. The stage representing the attainment of typical female
and male, plant gametes, showing the normal primary sexual
dimorphism. Female gamete or egg — large, stationary (not
discharged from the gametangium), with abundant cytoplasm
and food supply ; male gamete or sperm — small, free-swimming
with cilia, and with a small amount of cytoplasm and food.

Examples: Volvox, Sphaeroplea.

Feb., 1922 sexual evolution in the plant kingdom 105

6. Hermaphroditic condition with a definite dimorphism
showing in the gametangia but not in the contiguous regions or
only to a very slight extent. In these plants the sex is deter-
mined in the incipient gametangia.

Examples: Monoblepharis, Vaucheria sessilis, Coleochsete.

7. Hermaphrodites having a greater or less area of tissue
immediately beyond the gametangia proper showing sexual
dimorphism. The sexual state is determined in the tissues
before the definite origin of the gametangia and so influences
the morphological expression in the tissues below them.

Examples: Chara, Nitella.

8. Hermaphrodites having considerable areas of their
bodies differentiated as male or female tissues or branches from
which only spermaries or ovaries are produced. The sex is
determined in the vegetative tissue or branch long before
gametangia are developed.

Examples: Vaucheria synandra, Oedocladium protonema.
Fucus evanescens.

9. The culmination stage in the series represented by uni-
sexual individuals of various degrees of intensity and stability
of the male or female state and showing some dimorphism in
the entire individual. The sexual state in such individuals is
determined either in the gametes before fertilization, in the
zygote, or in a very early stage after germination of the zygote.
There are probably two progressive phases, which, however, can
usually be determined only by experiment: (a) Species in
which sexuality is not strongly fixed, that is the hereditary con-
stitution is such that a reversal of the sexual state is readily
brought about in the individual, (b) Species in which the sexual
state, either male or female, seems to be strongly fixed in the
individual, so that it becomes difficult to change from one sexual
state to a neutral state or from one sexual state to the other.

Examples: Oedogonium lautuniniarum, Fucus vesiculosus,
Mucor stolonifer (specialized sexual condition).

HI. HOMOSPOROUS SERIES WITH ANTITHETIC ALTER-
NATION OF GENERATIONS.

In this series the sporophyte shows no sexual differentiation
whatever, but in some species there may possibly be a physi-
ological difference in the spores with some cytological dimor-

106 JOHN H. SCHAFFNER Vol. XXII, No. 4

phism, as a chromosome difference, for example. The sporophyte
is nonsexual in expression in every respect although it carries
sexual potentialities in its cells in a latent condition. These
potentialities become evident in such abnormal cases as
apospory. The sporophyte in normal conditions is entirely
neutral in respect to sex, while the gametophyte shows all
gradations from hermaphrodites with closely associated sex
organs to extreme, unisexual individuals.

10. The lowest stage of this series is represented by species
with haploid, hermaphroditic gametophytes having the ovaries
and spermaries closely associated. Examples: many liverworts
and mosses (synoicous condition).

11. Haploid gametophytes which are hermaphrodites, but
which have distinctly differentiated male and female areas.
Examples: many ferns, mosses, and liverworts as Lophocolea
heterophylla (paroicous condition).

12. Haploid hermaphroditic gametophytes which have the
male and female organs on distinct branches or axes. Examples:
many liverworts, bog-mosses, and mosses, as Phascum cus-
pidatum (autoicous condition).

There are, of course, practically all possible intergradations
between stages 10, 11 and 12.

13. Haploid gametophytes differentiated into male and
female individuals (unisexual) but which may be reversed in
sex, either normally through age and growth or artificially by
being subjected to the proper environment.

Examples : Equisetum arvense, Matteuccia struthiopteris.

Note: There are also many species especially among the
liverworts and mosses which have part of the individuals uni-
sexual and part hermaphroditic (imperfectly unisexual), as
Cephalozia curvifolia.

14. Haploid gametophytes differentiated into male and
female individuals and these apparently not reversible by
known experimental means or reversible only rarely; often
showing a high degree of sexual dimorphism; in a few cases
at least, but apparently not often, with a difference in size of
synaptic chromosomes which are associated with the two sexes.

Examples: Sphaerocarpus, Marchantia, Polytrichum.
Note: Marchantia polymorpha is occasionally hermaph-
roditic.

Feb., 1922 sexual evolution in the plant kingdom 107

IV. HETEROSPOROUS SERIES WITH ANTITHETIC ALTER-
NATION OF GENERATIONS, THE GAMETOPHYTES
BEING UNISEXUAL AND THE SPOROPHYTE INDIVID-
UALS BISPORANGIATE OR AlONOSPORANGIATE.

In this series the sporophyte shows dimorphism at least in
the spores and sporangia. The gametophyte generation is appar-
ently always unisexual with distinct male and female individ-
uals highly differentiated both in morphological and physiolog-
ical characteristics. Normally, the sexual state of the gameto-
phytes is irreversible and determined even before the spores
are produced from which they originate.

15. The lowest stage of this series is represented by plants
whose bisporangiate sporophytes have only a slight dimorphism;
only the spores and sporangia are differentiated and show male
and female expression. The two kinds of sporangia are devel-
oped side by side on the same leaflet and sorus. The sexual
expression is controllable to a slight extent by artificial means.

Example: Marsilea.

Note: It must be remembered that this condition is evolv-
ing from a sporophyte that shows absolutely no sexuality in
morphological expression in any part of its body but that its
cells are, nevertheless, potentially sexual, the gametophytes
possessing a high degree of sexual dimorphism.

16. The first advance on the preceding condition is slight
but important. This stage is represented by bisporangiate
sporophytes with distinct microsporangiate and megasporan-
giate sori which develop into sporocarps but on the same leaf
and which may be side by side. The sexual state is determined
considerably earlier than the incepts of the sporangia in the
group of cells or in the tissues from which the entire sorus is
developed. The given sexual state must, however, be rather
weak at first since vestiges of the opposite organs appear.

Examples: AzoUa caroliniana and Salvinia natans.

Note: The megasporangiate sorus of Azolla contains ves-
tigial microsporangia and the microsporangiate sorus contains
a vestigial megasporangium, plainly showing that the mono-
sporangiate condition of the sorus was derived from an original
bisporangiate sorus as in Marsilea, the beginning of the sexual
state being thrown back to some extent. The change from one
sexual state to the other in the incipent sporangia inhibits the
full development.

108 JOHN H. SCHAFFNER Vol. XXII, No. 4

17. Bisporangiate sporophytes with the entire sporophylls
more or less differentiated and with but one kind of sporangia,
but the sporophylls arising side by side from a common stem
tissue. The typical state of the higher plants.

Examples: Selaginella, Bennettitites, Magnolia, Aquilegia,
Lilium, Cypripedium, Lactuca.

18. Monecious sporophytes in which the entire floral axis
with its parts is differentiated, the staminate and carpellate
flowers commingled more or less closely and showing large
vestiges of the opposite set of organs.

Examples: Cocos, Aesculus.

Note: The suppression of the opposite set of sporophylls is
of every degree, from this stage on, and has no relation to the
area of tissue involved in the sexual differentiation. There are
species in which the axis of the inflorescence is at first neutral
and gives rise to bisporangiate flowers below and then changes
above to a condition leading to the male state when only
staminate flowers are produced.

Example: Lophotocarpus calycinus. Such species have an
intermediate position between stages 17 and 18.

19. Monecious sporophytes having the axis of the inflo-
rescence differentiated, the staminate flowers being developed
first and, by a reversal of the sexual state, the carpellate later,
or more commonly the carpellate flowers first and the staminate
later.

Examples: Cymophyllus fraseri, Carex nardina, Tripsacum
dactyloides, Zizania aquatica, Ricinus communis, Musa sapi-
entum, Stillingia sylvatica. Typha latifolia.

In such inflorescences bisporangiate or abnormal flowers
frequently appear on the neutral transition zone where the
sexual state changes from one condition to the other.

20. Monecious sporophytes having an entire branch or
inflorescence determined as staminate or carpellate.

Examples: Carex lupulina, Euchlsena mexicana, Zea mays
(normal form).

21. The lower type of diecious sporophytes having only a
moderate reduction in the size of the opposite sporophylls in the
monosporangiate flowers, with frequent reversals to the oppo-
site sexual condition — staminate plants developing carpellate
flowers and carpellate plants staminate flowers.

Feb., 1922 sexual evolution in the plant kingdom 109

Examples : Acer platanoides, Acer rubrum.

There are, of course, interesting intermediate developments,
as for example one type of individuals may be monecious and
the other purely staminate. An example of this condition is
Arisaema dracontium.

22. Diecious sporophytes with complete or nearly complete
suppression of the opposite set of organs, in normal cases in all
the flowers of an individual, and having a more or less decided
vegetative dimorphism. These diecious sporophytes often have
a considerable percentage of intermediate individuals or are
known by experiment to show frequent reversals in sexual
expression, either through mutations, or through the influence
of the environment.

Examples: Arissema triphyllum, Morus alba, Morus rubra,
Cannabis sativa, Humulus japonicus, Mercurialis annua.

23. The last and most extreme type with diecious sporo-
phytes apparently without intermediates and not readily or
not at all reversible in sexual expression. When the sexual
state is once established, the staminate plants remain pure
staminate and the carpellate pure carpellate.

Examples: Acer negundo, Populus deltoides, Fraximus
americana.

Note : As stated, by such species is represented the extreme
limit of evolution in relation to sexual expression. The gameto-
phyte consists of pure male and female individuals apparently
irreversible in the normal environment, and the sporophyte
consists of pure staminate and carpellate individuals whose
sexual state is apparently fixed in their normal environmental
conditions. It is probable, however, that all diecious sporo-
phytes will be found reversible as to sex under the proper
environment during development. In these plants both the
gametophytes and sporophytes are dimorphic. The sexual
state of the gametophyte is determined in the previous sporo-
phyte generation and the sexual state of the sporophyte is
determined either in the gametes before fertilization, in the
zygote at the time of fertilization, or in the embryo after the
germination of the zygote.

110 JOHN H. SCHAFFNER Vol. XXII, No. 4

DISCUSSION OF THE FOREGOING SERIES.

From a study of the preceding series of species and their
numerous near relatives, from the lowest manifestation of
sexuality to the highest, it becomes evident that sexuality in
respect to its influence on the morphology of the vegetative
structures has been a gradual evolution making a slow and
almost uniform progress to the ultimate species, while the
evolution of the gametes, although also showing fundamentally
a similar progression, was attained very early, so that usually,
when one passes a little beyond the unicellular forms and simple
filaments, one finds the same general differences between eggs
and sperms as are present in the highest types. The most
remarkable thing about the whole evolutionary progression is
the fact that very rarely does any step in advancement have
any direct relation either to the reduction or to the fertilization
stage. So it comes about that the determination of the sexual
state takes place in the vast majority of cases in the vegetative
tissues, at other times than the periods of reduction and fer-
tilization. On the other hand, since hereditary factors are
apparently properties of chromosomes, the characters of the
individual outside of its sexual state are in the vast majority of
cases predetermined by reduction and fertilization. The
environment merely determines the degree of hereditary expres-
sion or the time of the expression in the life history.

We can then postulate the phenomena of sexuality as dis-
tinct from hereditary units. Probably ordinary hereditary units
are irreversible properties of specific parts of the chromatin and
cannot be changed except by mutation, while sexual states
are due to fundamental properties of the protoplasm or its
secretions due to a chemical or physical condition of the mole-
cules or atoms and so any given organic structure may pass
from the female to the neutral and then to the male state, or in
any direction from one of these states to the other without any
change in the hereditary factors whatever.

Cells may, therefore, be absolutely nonsexual or potentially
sexual. The potentially sexual may be in the male, female, or
neutral state in varying degrees of intensity. It has been the
practice of morphologists to designate individuals and genera-
tions in an antithetic cycle as "nonsexual" and there is no
special objection to this although "neutral" individual or gen-

Feb., 1922 sexual evolution in the plant kingdom 111

eration might perhaps define the condition somewhat better,
but objections might also be raised to this term as apphed
to heterosporous sporophytes. If we designate individuals by
the kind of reproductive cells they produce, then there is no
confusion in designating the sporophyte as "nonsexual." It is
probably best at present to hold that the low^est forms are
entirely nonsexual and not merely neutral, because their proto-
plasts apparently do not have the proper complexity of organ-
ization which would permit of or lead to sexual states.

The first differentiation then, as shown above, is in the
gametes themselves, and apparently the most fundamental
manifestation of sexuality is one of reaction or attraction of
two cells (gametes) toward each other. If the sexual state
arises in a cell, destined to be a gamete, after its morphological
expression is practically completed then there can be no struc-
tural dimorphism, but the earlier the maleness or femaleness is
established in the cell the more extreme the dimorphism must
become. Since there can be only a short transition between the
two extremes of isogamy and heterogamy the normal hetero-
gamous state is soon attained, often with little or no advance
in the evolution of vegetative parts, as stated before. The
typical egg as has long been known, is comparatively large with
a large amount of cytoplasm and food content and is nonmotile,
lacking cillia and flagella, while the sperm is small and motile,
being provided with cilia or flagella. These distinctions are true
for the great majority of types of plants and animals, from the
lowest heterogamous species to the highest. The greatest
deviation is in respect to the motile organs of the sperm, which
are absent in the rhodophyta, strobilophyta, and anthophyta.
In other respects, however, the typical dimorphism is not
materially altered. Secondary sexual characters begin to appear
when a given sexual state is established in the neutral veg-
etative cells whose descendants are not all transformed into
gametes or when a given sexual state is established in cells
which are destined to produce vegetative structures only or at
least before the final gamete-producing tissue is developed.
Finally the dimorphism may involve the entire individual. In
this case the sexual state must be present in the spore from
which the individual develops or soon after its germination.
The conditions which determine whether a cell or tissue shall
pass into the male or female state are probably diverse, but

112 JOHN H. SCHAFFNER Vol. XXII, No. 4

favorable and unfavorable nutritive conditions and maturity
or senility seem to be among the most important factors. Dis-
turbances brought about by unequal distribution of autosomes
or characteristic distributions of allosomes appear also to be
conditions bringing about or influencing sexual states, probably
by an influence on the metabolism of the cell. Besides these
cases in which sexual states are associated with slight differences
in chromosome numbers are those in which a haploid or diploid
set may be associated with one sex or the other. It is well-
known, however, that doubling the number of chromosomes in
a gametophyte does not necessarily disturb the sexual condition.
It would appear that in cells with allosomes sex reversal should
be more difficult to bring about than in cells which have equal
distributions of chromosomes, but this is for future
experiments to determine. It is well known that in numerous
cases secondary sexual characters are reversed in spite of the
presence of allosomes. The probable reason that secondary
sexual characters become more prominent in the higher forms is
because the protoplast contains a greater number of hereditary
factors which can be influenced by the sexual state at the time
of their expression of characters.

It becomes evident that sex cannot be associated primarily
with special chromosomes. The hypothesis of homozygous or
heterozygous combinations as determiners and controllers of
any given sexual state falls entirely outside of the complex
phenomena to be explained. Neither hereditary factors for sex
nor factors which control sex are in evidence; for in the vast
majority of plants the sexual state is determined in the somatic
cells in which neither segregation nor association of chrom-
osomes is taking place. So far as the gametophyte is concerned,
after passing through the evolutionary phase where her-
maphrodites are the rule, it is illuminating in the highest degree
to find that when the complete segregation of sex was attained
in the gametophyte it was not at all by the separation of units
with sexual control in the reduction division, but at a different
stage of the life cycle, namely, in the vegetative cells of the
sporophyte. Thus the megasporocytes do not segregate male-
ness from femaleness nor any properties or hereditary factors
which exercise a control over sexual expression, but all the cells
of a megasporocyte are differentiated with femaleness, and
give rise to female gametophytes, and in the same way the

Feb., 1922 sexual evolution in the plant kingdom 113

microsporocytes give rise to four microspores, as the result of
reduction, and all of the four develop into male gametophytes.
The reduction division in this case as in others segregates the
chromosomes with their complements of Mendelian factors,
but sexuality is not involved in such segregation and is not
affected or changed by it. It is, therefore, self evident that
fundamental sexual phenomena are caused by properties in
plants entirely apart from Mendelian units.

The specific structures and functions developed in the
ontogeny of an organism appear to be conditioned on the inter-
action of four fundamental influences: (1) the hereditary fac-
tors themselves, apparently properties of the chromosomes;

(2) the influence of the environment, both external and internal;

(3) the progression of senility, probably including a fundamental
exhaustion and degeneration of the protoplast as well as
retardation or change of its activities due to chemical deposits;
and (4) the presence of sexual states in the living substance,
through which primary and secondary sexual characters and
functions are produced and which are probably positive and
negative states of atoms or molecules contained in the living cell.

A NEW SPECIES OF PLEA
(HEMIPTERA-NOTONECTID^)*

CARL J. DRAKE
Department of Forest Entomology, New York State College of Forestry

The genus Plea of Leach, Trans. Linn. Soc. London, XII,
1817, pp. 11 and 13, is represented in North America by a single
described species. Plea striola Fieber. During the past summer,
1921, the writer collected seven specimens of an apparently
undescribed species in a small stagnant . pond near Fayette,
Miss. The insect is named in honor of Prof. R. W. Harned, who
is taking a very active interest in the insect fauna of Mississippi.

Plea harnedi n. sp.

Yellowish gray, the fuscous markings large and prominent. Size
small, not twice as long as broad, smooth, somewhat shining, quite
coarsely and rather closely punctured, many of the punctures with a
very short, inconspicuous, decumbent hair (visible under the high
power of binocular). Dorsal surface somewhat flattened at the
scutellum. Elytra short, of a uniform structure, very declivous pos-
teriorly, each elytron, like in P. minutissima (Fussl.) of the Palaearctic
region, divided into two distinct areas, the clavus and the corium.
Wings well developed, folded beneath the elytra and thus entirely con-
cealed from view when not in use. Head strongly punctured, with a
large median, triangular, brown or fuscous area between the eyes. The
eyes reddish brown or black. Scutellum fuscous, the apex yellowish
gray. Pronotum largely fuscous, a median rectangular spot back of
the collum, the sides and posterior margin yellowish gray. The fuscous
areas of the elytra and pronotum slightly variable in size. Rostrum
and body beneath blackish. Legs yellowish brown, the coxae and
trochanters blackish, the tips of the femora and of the third tarsal
segments fuscous. Posterior legs with numerous hairs along the inner
margins. Length, 2.27 mm.; width, 1.2 mm.

Seven specimens, taken in a small artificial pond, July 23,
1921, a few miles from Fayette, Miss. Type in my collection.
Paratypes in the National Museum, Mississippi Agricultural
College and my collection. As the species is very distinct and

* Contributions from the Department of Entomology, the New York State
College of Forestry, Syracuse, N. Y., No. 38.

114

Feb., 1922

A NEW SPECIES OF PLEA

115

not easily confused with strioJa, I have not injured a couple
specimens of the type series in order to figure male and female
genitalia.

P. harnedi n. sp. may be readily separated from P. striola
Fieb. by the conspicuous color markings, the large triangular
(brown or fuscous) are between the eyes, and each elytron is
divided by a very deep suture into tw^o regions. In striola the
elytra are usually entire and the color, save a small median
streak between the eyes, is nearly a uniform yellowish gray;

CL

b

Fig. 1. Plea harnedi n. sp. a, dorsal aspect; b, lateral aspect.
From drawing by W. P. Osborn.

the elytra are also more highly arched behind and quite differ-
ently punctured. According to Dr. Hungerford the structure
of the elytra in striola (suture distinct or not) is a variable
character and not a satisfactory one. He states that some
specimens of striola in the National Museum show a distinct
suture (clavus present) and that in others it is pretty hard to
make out at all. My specimens of striola from Canada, Ohio,
New York, Pennsylvania, Florida and Mississippi, fail to show
a distinct clavus.

A number of other rather interesting aquatic and semi-
aquatic Hemiptera were taken in the same pond, near Fayette,

116 CARL J. DRAKE Vol. XXII, No. 4

Miss. In company with P. harnedi the writer collected spec-
imens of Ranatra fusca P. S. (Bueno & Montd.), Notonecta-
hoiuardi Bueno, Corixa n. sp. (fide Hungerford), Benacus griseus
(Say), Belostoma flumineum Say, Belostoma lutarium (Stal),
Pelocoris femoratus (P. B.). The following species were quite
common upon the surface of the water: Mesovelia mulsanti
White, Hydrometra martini Kirk., Hydrometra australis Say,
Gerris canalicidatus Say, Tenagogonus hesione Kirk., Trepobates
pictus (H. S.), Microvelia hinei Drake, Velia hrachialis Stal, and
Merragata brunnea Drake. Micracanthia humills (Say) was
captured upon some floating aquatic plants and Gelastocoris
cidatus Fabr. was quite common upon the moist ground
bordering the pond.

AN ANNOTATED LIST OF MISSISSIPPI
CHRYSOMELID^.

H. L. DOZIER

Slate Plant Board of Mississippi

While engaged in general scouting and inspection work in
Mississippi during the past year the writer took advantage of
the spare moments to collect and study the chrysomelids.
The resultant annotated list is given as an incentive to a more
complete one. Thanks are due to Dr. E. A. Schwarz and
Charles Dury for confirmation and identification of the speci-
mens. Those not otherwise credited were collected by the
writer.

Lema hrunnicollis Lac. Agr. College, Miss., April 7, 1920,
A. V. Smith coll.; Okolona, July 9, 1921, M. R. Smith; Pascag-
oula, August 5, 1921.

Lema trilineata Oliv. Rosebloom, Miss., Summer of 1915,
R. Buchanan; Agr. College, Miss., April 10, 1920. D. V.
Stapleton.

Lema sexpunctata Oliv. Ocean Springs, C. Forkert ; Agr. Col-
lege, May- June, 1920; Vicksburg, July 15, 1921.

Lema sayi Crotch. Agr. College, March-April.

Antipus (Anomaea) laticlavia Forst. Blue Mountain, July 2,
1914, H. H. Carter; Vimville, August 1, 1914, E. R. Rainey;
Agr. College, May-Sept.

Bahia quadriguttata Oliv. Agr. College, April-May.

Saxinis omogera La. Longview, June 27, 1920; Agr. College,
July 20, 1920, A. Mcintosh; several specimens.

Chlamys plicata Fab. Pascagoula, July 10, 1920, swept in
abundance from floor of low pine flatwoods; Helena, July 13,
1920; Aberdeen, April 5, 1921, sweeping in pine woods.

Exema gibber Oliv. Pascagoula, July 10, 1920, sweeping floor
of low pine flatwoods.

Pachybrachys lodingi Fall. Pascagoula, sweeping floor of low
pine flatwoods, July 10, 1920.

Pachybrachys atomarius Melsh. Agr. College, S. F. Potts.

Pachybrachys roboris Fall. Agr. College, July 11, 1913, J. G.
Hester, on pecan.

117

118 H. L. DOZIER Vol. XXII, No. 4

Pachybrachys atomarius var. Pascagoula, swept in abundance
from floor of low pine flatwoods, July 12, 1920.

Pachybrachys bivittatus Say. Agr. College; Woodville, July
26, 1921, abundant on willow.

Pachybrachys autolycus Fall. Cat Island, several swept
from Jimcus vegetation, September 7, 1920.

Pachybrachys vidimtus Fabr. Ocean Springs, July 29, 1920;
Longview, a number taken sweeping in deciduous woods,
June 27, 1920; Hattiesburg, August 10, 1921.

Pachybrachys vidimtus var.? Big Point, July 15, 1920;
Pascagoula, June G, 1920, flatwoods.

Pachybrachys intricatus Sufiir. Dennis, June 6, 1921.

Pachybrachys luridus Fabr. Longview, several sweeping
in low deciduous woods, June 27, 1920.

Pachybrachys subfasciatus Blatch. Agr, College, June 4,
1915. C. C. Greer.

Pachybrachys hepaticus Melsh. Cat. Island; a single speci-
men taken sweeping in a stand of Jimcus, Sept. 7, 1920.

Monachulus (Monachus) auritus Hald. Pascagoula, July
10, 1920; Rara-avis, July 5, 1921, M. R. Smith.

Cryptocephalus quadruplex Newn. Agr. College.

Cryptocephalus bivius Newn. Agr. College, September 29,
1915, W. Gernon.

Cryptocephalus venustus Fabr. Longview, June 27, 1920;
Agr. College, May-June.

Cryptocephalus obsoletus Germ. Pascagoula, sweeping floor
of low pine flatwoods, July 12, 1920, abundant; Helena, July
13, 1920; Maxie, August 19, 1920; Lumberton, August 26, 1920.

Cryptocephalus gibbicollis Hald. Agr. College, January 1,
1915, R. H. Batty; Bradley, July 14, 1921; Poplarville, July 28,
1921; Hattiesburg, August 10, 1921.

Cryptocephalus incertus Oliv. Fruitland Park, sweeping low
grass and foliage at edge of gum swamp, August 17, 1920;
Hattiesburg, abundant sweeping grassy floor of pine and black-
jack oakwoods, August 10, 1921; Pascagoula, August, 1921;
Biloxi, August 1, 1921.

Cryptocephalus sp. Maxie, a single specimen of a very
small brown species so far unidentified and perhaps new,
August 19, 1920; Ocean Springs, August 3, 1921.

Diachus auratus Fabr. Ocean Springs, July 24, 1920; Agr.
College, H. E. Weed; Verona, July 9, 1921.

Feb., 1922 Mississippi chrysomelid^ 119

Bassareus hrunnipes Oliv. Agr. College, abundant sweeping
weeds; June 21, 1920; Big Point, July 15, 1920; Poplarville,
July 27, 1921; Gulfport, August 1, 1921.

Chrysodma globosa Say. Rara-avis, July 5, 1921, M. R.
Smith.

Nodononta tristis Oliv. Bovina, July 2, 1904, T. D. Kilne;
Utica, July 1, 1905, J. B. Dudley; Bassfield, T. N. Gillan.

Colaspis brunnea Fab. Agr. College, common; Millville,
June 24, 1904, J. L. Norman; Roxie, June 20, 1910, S. F.
Blumenfeld; Utica, June 17, 1920, Blumenfeld; Gloster, June
20, 1920, Blumenfeld.

Colaspis favosa Say. Pascagoula, numbers taken sweeping
floor of low pine flatwoods, July 12, 1920; Agr. College, H. E.
Weed.

Rhabdopterns picipes Oliv. Longview, sweeping in deciduous
woods, June 27, 1920; Fruitland Park, August 17, 1920; Agr.
College, June 29, 1915, J. L. E. Lauderdale.'

GrapJiops marcassitiis Cr. Pascagoula, a number taken
sweeping floor of low pine flatwoods, July 12, 1920; Ellisville,
sweeping floor of high pine land, August 24, 1920.

Fidia longipes Melsh. Agr. College, May '93, H. E. Weed;
Como, June 12, 1911, M. W. Weston; Natchez, June 8, 1895,
H. E. Weed.

Metachroma laevicollis? Cr. Pascagoula, July 12, 1920.

Metachroma quercatum Fab. Big Point, L. Brown, numbers
on pecan, April 29, 1915; Big Point, D. Cunningham, abundant
on pecan, May 5, 1915.

Tymnes tricolor Fabr. Agr. College, April 16, 1919, J. W.
Patterson.

Myochrous denticollis Say. Fayette, April 27, 1910, R. H.
Truly'; Crystal Springs, May 9, 1910, R. E. Gates; Phillip,
May 14, 1910, R. W. Harned; Pascagoula, numbers swept
from floor of low pine flatwoods, July 6, 1920; Ocean Springs,
July 29, 1920.

Glyptoscelis pubescens Fab. Agr. College, May 6, 1917,
C. H. Reems.

Paria canella var. quadrinottatus Say. Longview, sweeping
in low deciduous woods, April 9, 1921.

Paria canella var. quadrigiittatiis Lac. A number beaten
from willow at Nettleton, March 27, 1921.

120 H. L. DOZIER Vol. XXII, No. 4

Paria canella var. atterimiis Oliv. Pascagoula, July 12,
1920, flatwoods.

Chrysochus auratus Fabr. Agr. College, April 18, 1914,
V. E. Critz; Agr. College, October 14, 1914, R. E. Jackson;
Oxford, June 16, 1919, F. M. Hull; on Asclepias.

Labidomera clivicollis Kby, Macon, September 16, 1919,
J. T. Douglas; Agr. College, April 24, 1917, E. B. Johnson;
June 10, 1919, G. B. Ray; October 26, 1920, J. B. Boswell.

Leptinotarsa decemlineata Say. Abundant over most of the
State. April-October.

Leptinotarsa juncta Germ. Several taken in State.

Zygogramma suturalis Fabr. Agr. College, March, 1916,
R. C. Pittman.

Calligrapha pvaecelsis Rogers. Agr. College, 1916, G. C.
Horton.

Calligrapha philadelphica Lee. Agr. College, April and
May; Brookhaven, August, 1919, K. W. Holloway; Maxie,
August 19, 1920; Nettleton, March 27, 1921, on willow.

Lina inter riipta Fab. Agr. College, April, 1920, B. R.
Gunn; Poplarville, May 3, 1921, M. H. Mabry.

Lina scripta Fab. Vimville, August 1, 1914, E. R. Raney;
Agr. College, April 2, 1919, M. E. Kelly; Scott, July, 1919,
C. H. Brannon; Leflore Co., July, 1919, R. R. Spann; Agr.
College, July 20, 1920, A. Mcintosh.

Monocesta coryli Say. Agr. College, October, 1895, one
adult and two larvae, H. E. Weed.

Galerucella americana Fab. Pascagoula, July 12, 1920,
abundant in sweeping floor of low pine flatwoods; Lyman,
July 28, 1921.

Galerucella notulata Fab. Pascagoula, July 12, 1920, several
taken in flatwoods.

Galerucella notata Fab. Baxterville, July 27, 1921, sweeping
floor of open pine flatwoods.

Diabrotica 12-punctata Fab. Generally distributed over
the entire State, attacking corn, beans, alfalfa, etc.

Diabrotica balteata Lee. Agr. College, October 26, 1915, on
corn, E. B. Huston; Fayette, October 2, 1916, Mrs. J. C.
McNair; Ocean Springs, July 24, 1920; Biloxi, August 12, 1920.

Diabrotica atripennis Say. Okolona, several taken June
26, 1921.

Feb., 1922 Mississippi chrysomelid^ 121

Diahrotica vittata Fab. Laurel, August 2, 1916, M. G.
Dyers; Houlka, J. R. Plamilton; Buena Vista, H. L. King;
Shubuta, C. E. Brashier; Ratliff, A. Mcintosh; Agr. College,
F. H. Jones; Aberdeen, April 5, 1921.

Diahrotica tricincta Say. Agr. College, summer 1919, B. H.
Virdon. This record is questioned and the specimen is probably
from Texas.

Phyllobrotica limbata Fab. Hattiesburg, 1916, H. Cook.

Luperodes varicornis Lee. Kirby, July 10, 1915, on corn in
numbers, R. L. Saxon; Johns, July 1, 1915, numerous on corn,
D. G. WilHams.

Ceratoma trifurcata Forst. Abundant throughout the State
on beans.

Blepharida rhois Forst. Longview, May 16, 1914, E. H.
Byrd; Agr. College, April-October, on sumach; Amory, March
26\ 1921.

Oedionychis gibhitarsa Say. Agr. College, April 16, 1915,
A. Berret;'May 16, 1915, W. H. Calcata; March 30, 1919, R. L.
Price; Pascagoula, July 5, 1920, abundant, sweeping roadside
vegetation near river; Agr. College, April 18, 1920, J. N.
Crisler.

Oedionvchis tlwracica Fab. Agr. College, March 20, 1918,
R. J. Coker.

Oedionychis vians 111. Agr. College, October 26, 1918,
A. Hammet; Helena, June 13, 1920.

Oedionychis petaiirista Fab. Longview, June 27, 1920,
several taken sweeping in deciduous woods; Pascagoula,
numbers taken sweeping floor of low pine flatwoods, July 10,
1920.

Oedionychis miniata Fab. Pascagoula, July 12, 1920, flat-
woods; Agr. College, H. E. Weed; Baxterville, July 27, 1921.

Oedionychis indigoptera Lee. Hattiesburg, August 10, 1921,
a single specimen.

Oedionychis thyamoides Cr. Agr. College, abundant April-
May; Longview, June 27, 1920; Amory, March 27, 1921;
Aberdeen, April 5, 1921; Gibson, June 27, 1921.

Oedionychis siitiiralis Fab. Shubuta, C. E. Brashier; Big
Point, July 15, 1920; Ocean Springs, July 24, 1920.

Oedionychis quercata var. obsidiana Fab. Big Point, July 15,
1920; Pascagoula, July 6, 1920, flatwoods.

122 H. L. DOZIER Vol. XXII, No. 4

Oedionychis quercata var. Amory, March 27, 1921; Tibbee,
April 5, 1921, abundant on ash.

Oedionychis quercata var. Tibbee, April 5, 1921, abundant
on ash.

Oedionychis scalaris Melsh. var. Pascagoula, July 10, 1920.

Oedionychis sexmaculata 111. Agr. College, April 3, 1921.

Disonycha pennsylvanica 111. Agr. College, H. E. Weed.

Disonycha caroliniana Fab. var. Baxterville, July 27, 1921,
in pine flatwoods.

Disonycha qimtqnevittata Say. Agr. College, May 5, 1914,
K. V. Jones.

Disonycha glahrata Fab. Agr. College, June 23, 1920;
Tylertown; Port Gibson, July 21, 1921.

Disonycha abbreviata Melsh. Agr. College, May, 1920, B.
Boswell; Woodville, July 25, 1921; Meridian, August 14, 1921.

Disonycha collata Fab. Agr. College, March 29, 1919, A. V.
Knight.

Haltica polita Oliv. Baxterville, July 27, 1921, flatwoods;
Belmont, June 7, 1921.

Haltica rnfa 111. Longview, June 27, 1920, one specimen
taken in deciduous woods.

Lactica ocreata vSay. Oxford, summer 1920, F. M. Hull.
Abundant on passion flower.

Chalcoides helxines L. Extremely abundant on willow
throughout the State.

Crepidodera erythropus Melsh. Agr. College, October 20,
1917, D. Q. Segres't.

Epitrix parvula Fab. Meadville, C. F. Cain.

Epitrix cucumeris Harris. Agr. College, H. E. Weed;
Sardis, 1S9.5, T. A. Mitchell.

Chaetocnema pulicaria Melsh. Agr. College, H. E. Weed.

Chaetoc?iema dcnticidata 111. Ocean Springs, July 29, 1920.

Chaetocnema alutacea Cr. Helena, July 13, 1920, sweeping
in low pine flatwoods; Big Point, July 13, 1920.

Systena hndsonias Forst. Longview, June 27, 1920.

Systena frontalis Fab. Helena, July 13, 1920.

Systena pallipes Sz. Biloxi, July 30, 1921. A single
specimen.

Feb., 1922 Mississippi CHRYSOMELiDiE 123

Svstena elongata Fab. Fayette, June 18, 1910, S. F. Blumcn-
feld;'Utica, June 17, 1910; Agr. College, June 22, 1920.

Systena taeniata Say. Abundant throughout the State.

Systena niarginalis 111. Longview, June 27, 1920.

Longitarsiis testaceous Melsh. Agr. College, October, 1895,
H. E. Weed.

Longitarsiis melaiuinis Melsh. Agr. College, H. E. Weed.

PhyUotreta vittata Fab. Agr. College, May G, 1915, J. W^
Bailey, feeding on cabbage; Tupelo, March 22, 1921, in garden.

PhyUotreta picta 111. Artesia, May 1, 1921, swept from
roadside vegetation.

PhyUotreta oregoneusis Cr. Natchez, June 8, 1895, H. E.
Weed. A doubtful record.

Dibolia borealis Chev. Agr. College, H. E. Weed.

PsyUiodes convexior Lee. Agr. College, October and Novem-
ber, 1895, H. E. Weed.

Chalepiis nervosa Panz. Agr. College, April 3, 1921.

Chalcpus bicolor Oh v. Pascagoula, July 10, 1920; F^llisville,
sweeping floor of high pine land, August 24, 1920; Ocean Springs,
July 29, 1920; Fruitland Park, August 17, 1920; Golden,
June 5, 1921; Baxterville, July 27, 1921; Hattiesburg, August
10, 1921.

Chalepiis scapidaris Oliv. Agr. College, March 20, 1910,
J. L. E. Lauderdale; Longview, sweeping in deciduous woods,
June 27, 1920.

Chalepus notatus Oliv. Big Point, July 15, 1920.

Chalepiis rubra Weber. Agr. College, July 1911, L. N.
Felton; Longview, April 9, 1921, sweeping in low deciduous
woods.

Chalepus honiii Smith. Golden, July 5, 1921; Belmont,
July 7, 1921, a number of specimens swept probably from a
small legume on forest floor.

Octotoma plicatiila Fab. Agr. Cohege, April 29, 1921, F. M.
Hull; Woodvihe, July 20, 1921.

Uroplata porcata Melsh. Pascagoula, July 6, 1920, sweeping
floor of low pine flatwoods; August 5, 1921.

Microrhopala excavata Oliv. Golden, July 5, 1921, a single
specimen taken sweeping floor of open high mixed pine and
deciduous woods on hillside; Gulfport, August 1, 1921.

124 H. L. DOZIER Vol. XXII, No. 4

Desmonota variolosa Weber. Columbia, July, Q. E. Morris;
Agr. College, several collected on sweet potatoes by J. W.
Bailey. As this is a tropical species and not known heretofore
from the U. S., I consider both of these records rather doubtful.

Gratiana (Cassida) pallidula Boh. Agr. College, May 3,
1921, C. J. Havens.

Coptocvda clavata. Agr. College, May 15, 1921, F. M. Hull.

The Ohio Journal of Science

Vol. XXII March, 1922 No. 5

SOME SUB-SURFACE ROCK CHANNELS AND

CAVITIES FILLED WITH GLACIAL

MATERIAL.

J. ERNEST CARMAN
Department of Geology, Ohio State University

DESCRIPTION OF DEPOSITS.

At Silica, in Lucas County, Ohio, about ten miles west of
Toledo, is a large quarry which shows a face about twenty feet
in height and about one-fourth of a mile long, extending N-S.
and facing east. The strata exposed are in the upper part of
the Lucas dolomite and they dip westward at an angle of about
five degrees.

Along the south part of this quarry face at about 15 feet
beneath the top there was exposed in 1921 a zone of light
drab dolomite, three to four feet thick, containing a number of
cavities that are lined and partially filled with large crystals
of calcite of the dog-tooth form. These spaces, or former
spaces now partly filled, commonly appear as lense-shaped in
the quarry face and are one to three feet long and six to twelve
inches high.

Associated with the dolomite and calcite of this zone there
is a considerable quantity of fine grained silt clay. Most
of it is greenish or greenish-blue in color, but brown and other
dark shades exist. Most of it is laminated, but some is compact
without laminae. It is very tough and when wet sticks to
the hammer and tears like putty. When dry it is very hard
and breaks with a direct even fracture. Most of this clay
is without grit. At many places the clay rests against and fits
around the projecting dog-tooth calcite cr^^stals. It was found
also in sharp lateral contact with the dolomite and even filling

125

126 J. ERNEST CARMAN Vol. XXII, No. 5

small irregularities in the roofs of the former cavities. The
clay exists in masses two to three feet across and in such
quantity that in wet weather it causes considerable trouble
in the crushing plant, because it clogs in the crushing burrs
and prevents the rock from dropping into them. The larger
masses are dumped to one side by the steam shovel and not
loaded on the cars.

At several places sand is associated with the clay and at a
few places there is gravel containing pebbles and cobbles,
some of the latter being four to six inches through. The most
common rock among the pebbles and cobbles is the Monroe
dolomite, but basalts, granitoids and foreign sedimentaries
exist. Some of the pebbles are well rounded and some are
subangular. All of this material is relatively fresh. Most
of the quarry face was a confused mass of blasted stone, but
where the form of the clay deposits could be determined it
was found that if gravel and sand exist they are at the bottom
and at most places are overlaid by the clay. A few cases of
very fine sand interbedded with clay exist. Surfaces of pro-
jecting dog-tooth calcite crystals are buried in the sand, which
can be cleaned away from around the crystals.

One deposit in a tunnel in the rock gives such clear evidence
as to deserve special notice. The rock channel is three feet
six inches high and two feet wide at the widest part, and is
cut across at an angle by the quarry wall. In the bottom is
coarse gravel containing some cobbles up to six inches in
diameter. Above the gravel is about two feet of compact,
tough clay, blue in color, except for six inches at the top,
which is oxidized and yellow. Above the clay is an open
space about one foot high. The channel extends obliquely
into the quarry wall and at a distance of about five feet it
broadens out into a space four to five feet across, with about
two feet above the filling of clay. Farther in, the channel
narrows and the roof comes down until at a distance of about
20 feet from the quarry face there appears to be only four to
six inches of space above the filling.

ORIGIN OF DEPOSITS.

As to the origin of the clay deposits, it is evident that they
did not originate by weathering in place, but have been intro-
duced in some way. The characteristics of the clay suggest

Mar., 1922 cavities filled with glacial material 127

slack-water silt deposits such as are in many cases associated
with glacial deposits. The composition and shape of the
pebbles and cobbles and the amount of wear show that the
gravel is glacial material. How did it come to its present
position fifteen feet below the surface and apparently enclosed
in the dolomite? The stone above is compact, bedded dolomite
without any known natural opening through it. Numerous
drill holes have been sunk for blasting the stone and some of
these show on the quarry face, but the silt clay is very different
from the calcareous slime derived by wash from the drillings
and the packing used in the drill holes is distinct from the
sand and gravel filling.

The characteristics of abundant calcite, cavities more or less
filled with calcite, and the enclosed silt and gravel deposits,
are present along the quarry face for more than a hundred
yards; that is, these are characteristics of a zone. The strata
here dip west into the quarry wall at an angle of about five
degrees and if this zone is projected upward it would meet
the level of the general rock surface about forty-five yards east
of the present quarry wall. In fact, such a position of outcrop
is shown at the south wall of the quarry. The cavernous
character of this zone continued to the outcrop and it was
by these openings that the glacial material entered. The first
material carried down and deposited was sand and gravel with
cobbles. The coarser material was deposited only in or near
the more open channels like the one described above. Some
of the sand was carried into the smaller crystal-lined cavities
and deposited around the crystals.

The deposition of the clay followed that of the sand and
gravel. Much of it is laminated and the material is very fine
grained, indicating deposition from relatively quiet water which
apparently filled all the cavities of the zone. The deposition
continued until the cavities were completely filled, even to the
placing of laminated clay in small irregularities in the roofs
of the cavities. At other places the cavity filling was only
partial or absent entirely.

The ground water level of the region at the present time is
about 15 feet beneath the surface and it is evident that these
cavities go deeper than this, and in another quarry this same
zone contains much calcite filling, although few open spaces,
at a depth of 45 feet. It is not known to what depth the

128 J- ERNEST CARMAN Vol. XXII, No. 5

introduced glacial deposits extend, but their presence at 15
feet below the surface and the calcite filling at greater depth
show that the region was higher and the ground water surface
deeper at the time of the formation of the cavernous zone and
probably at the time when the gravels were carried down the
passages on a general five degree gradient. The clay on the
other hand gives evidence that the channels were filled with
water at the time of the clay deposition. This indicates a
higher water table, or deposition at the time that the region
lay beneath Lake Maumee and its successors. The general
similarity of these clays to the clay deposits of the old lake
bottom adds support to this latter interpretation. As the
waters of the lake bottom at this place were agitated, the fine
silt settled down into the water of the channels beneath, which
were more or less connected with the lake, and in these channels
and the connected rock cavities the clay deposition took place.

Two miles north of Silica a quarry, exposing the same
horizons as at Silica, shows this same cavernous zone with
crystal lined cavities. A fine grained clay was observed in
the cavities at eight feet below the rock surface and a workman
reported that they had found some very tough and sticky
clay in the cavities of this zone at 15 feet below the rock surface.
This clay is undoubtedly of the same type and origin as that at
Silica.

Considerable masses of tough, fine grained clay were seen
associated with the loose blocks of stone on the quarry faces at
the Holland quarry, seven miles south of Silica and at the
France Stone Company quarry, one mile south of Monroe,
Michigan. The clay was much like that seen at Silica, but in
neither of these places could it be so definitely connected with a
glacial origin.

THE CLASSIFICATION OF PLANTS. XII.*

JOHN H. SCHAFFNER
Department of Botany, Ohio State University

Eleven papers have been published previously by the
writer, giving a preliminary survey of the phyletic classification
of plants, and covering the whole ground except the Algae. The
first paper was published in the Ohio Naturalist, 5: 298-301,
1905, and subsequent papers appeared from time to time in
that journal. The present paper completes the series, but it is
the intention of the writer to continue the studies in a more
detailed manner, dealing with the phylogeny and taxonomy
of the various classes and subclasses.

The term Algae has reference to a physiological group and is
of the same convenience in dealing with the lower plants in a
practical way as the terms, trees, parasites, herbs, etc. It has
no taxonomic value. An alga may be defined as a thallophyte
with chlorophyll. The algae are largely aquatic organisms but
some species are able to endure aerial conditions as their normal
habitat.

The algae apparently belong to at least six distinct phyla
and a number of the classes have closely related fungi. Our
knowledge of the morphology and life histories of the algae is
still very imperfect, so any arrangement must be regarded as
more or less tentative. The writer has not been able to follow
those authors who divide the green algae primarily into Akontae,
Isokontae, and Heterokont^. Such a procedure seems decidedly
artificial. The Peridinieae are regarded as more animal-like
than plant-like and are thus removed to the Protozoa. Follow-
ing Oltmanns and others, the Diatomeae are placed near the
Conjugatae but only as a subphylum, since the relationship
can, at best, be only very remote. The agreement with desmids
in certain characters is nevertheless striking and both diatoms
and desmids may be regarded as derivatives from some prim-
itive filamentous group without zoospores, but which discharged
its isogamous sexual cells into the water with little change
from the vegetative character. Although the Oedogoniaies are

* Papers f-rom the' Department of Botany, The Ohio State University, No. 127.

129

130 JOHN H. SCHAFFNER Vol. XXII, No. 5

peculiar in many respects they are nevertheless plainly related
to the other filamentous green algae and the same is true of the
Siphoneae and related forms which according to the writer's
views do not warrant segregation into a distinct phylum as was
done by Bessey. On the other hand, the Charales are so aberrant
that their origin is very obscure and they have, therefore, been
placed in a distinct phylum.

SYNOPSIS OF THE ALGAL PHYLA

I. Cells typically with poorly differentiated nuclei and chromatophores, repro-
ducing by fission, motile and nonmotile, never with a pure chlorophyll-green
color, but containing phycocyanin; unicellular or filamentous, apparently
without sexuality. The most primitive of the algae and along with the
bacteria the most primitive of all organisms. Marine or mostly freshwater,
some species growing in very hot springs. Phylum, Schizophyt.\.

IT. Cells with well differentiated nuclei and usually with definite chromato-
phores; green or variously tinted by coloring matters.

A. Unicellular or filamentous plants containing chlorophyll, either of a
brownish or yellowish color and with silicified, two-valved walls, or
green with complex chromatophores or fantastic cells, the walls not
silicified; sexual or apparently nonsexual by degeneration; conjugating
cells not ciliated, isogamous. Phylum, Zygophyt.\.

L With silicified, valved cell walls, usually with fantastic forms and
markings, and usually of a yellowish or brownish color. Marine
and fresh water plants. Subphylum, Diatomeae.

2. Cell walls not silicified; plants filamentous or unicellular, green,
the unicellular often with fantastic forms and markings. Fresh
water plants. Subphylum, Conjugatae.

B. Plants not with silicified two-valved walls; usually with zoospores when
green, or with heterogamous sexuality, sometimes nonsexual, the iso-
gamous green forms usually not with fantastic chromatophores nor with
a constriction in the middle of the cell.

L Antheridium when present not consisting of a globular structure
containing sperm-bearing filaments; sometimes with an alternation
of generations.

a. Plants mostly green, nearly all producing nonsexual zoospores,
the sexual forms isogamous or heterogamous. Characteristic
water plants, but also numerous marine species.

Phylum, GONIDIOPHYTA.

b. Plants with the chlorophyll usually hidden by a brown, red, or
purple pigment always with a multicellular body and with
sexuality or apparently from sexual ancestors.

(a) Mostly marine, often large, brown algae with phycophaein;
isogamous or heterogamous or sexuality unknown, with
ciliated sperms, both gametes discharged from the game-
tangium. Phylum, Phaeophyta.

(b) Mostly marine red or purple algae with phycoerythrin;
heterogamous, with stationary eggs and non-ciliated sperms.

Phylum, Rhodophyta.

2. Filamentous, green algae with globular antheridia containing sperm-
bearing filaments, the sperms being biciliated; nonsexual spores
absent. In fresh or brackish water. Phylum, Charophyta.

Mar., 1922 classification of plants 131

SYNOPSES OF THE SEVERAL PHYLA

Phylum, ScHizoPHYTA. Fission Plants.

I. Without a definite nuclear membrane and with a low type of chromatophore.
Class, Cyanophyceae. Blue-green Algae. 1000 species.

A. Not filamentous; cells free or in masses or plates (superficial aggregates) ;
or the cell individuals with definite base and apex, in fruiting sometimes
forming a row of cells. Chroococcales. Chroococcaceae, Chamaesipho-
naceae.

B. Cells arranged in definite filaments.

L Filaments without hair-like tips, sometimes narrowed at the ends.

a. Without heterocysts; free filaments commonly massed into flat
layers, sometimes several filaments enclosed in one common
sheath. Oscillatoriales, Oscillatoriaceas.

b. With intercallary heterocysts. Nostocales. Nostocaces,
Scytonemataces, Stigonemataceas.

2. Filaments with hair-like tips at one or both ends. Rivulariales.
Camptotrichaces, Rivulariacese.
IL With nuclear membrane and highly differentiated chromatophores; uni-
cellular or in colonies. Class, GLAucocYSTEiE. 20 species. Glaucocystales,
Glaucocystaceas.

Phylum, Zygophyta. Conjugate Algas.

L Cell walls impregnated with silica, composed of two valves; chromatophores
3'ellow or brown, rarely green, containing chloraphyll and diatomin and a
variable number of pyrenoids. Subphylum and class, Diatome^. Diatoms.
5700 species.

A. Valves without a raphe or pseudo-raphe, with a concentric or ratiating
symmetry around a central point; valve view usually circular, polj^gonal,
or broadly elliptical in outline, rarely boat-shaped or irregular; con-
jugation unknown; cells without spontaneous movement. Mostly
marine plants. Eupodiscales. Round Diatoms. Eupodiscaceae, Sole-
niaceae, Biddulphiaceae, Rutilariaceae.

B. Valves with a raphe or pseudo-raphe or with a sagittal line, with a zygo-
morphic or isobilateral or sometimes irregular symmetry; never centric;
valve view mostly boat-shaped or elliptic in outline; motile or nonmotile;
conjugation known in most groups. Mostly fresh water plants.
Naviculales. LongDiatoms. Fragillariacece,Surirellacese,Achnanthacece,
Naviculacese.

IL Cell walls without silica, but with abundant development of gelatinous
pectose causing the plants to be slimy to the touch; chromatophores green,
with chlorophyll and one or more pyrenoids. Subphylum and class Con-
jugate. 2300 species.

A. Thallus a filament, or commonly separating into single cells, mostly
flattened, the cell wall usually divided into two symmetrical halves;
cells mostly constricted at the middle, often of fantastic and beautiful
forms; cell contents mostly divided into symmetrical halves; conjugation
by the breaking open of the cell walls or by the formation of a primitive
conjugation tube. Desmidiales. Desmids. 2100 species. Spiro-
taeniaceae, Desmidiaceae.

B. Thallus a simple filament, occasionally slightly branched, of cylindrical
cells, the cells not constricted in the middle, but sometimes the contents
divided into symmetrical halves; these latter forms distinguished from
the preceding order by the definite filament and prominent conjugation
tube; some species forming aplanospores. Zygnemales. Pond-scums.
200 species. One family, Zygnemaceas.

132 JOHN H. SCHAFFNER Vol. XXII, No. 5

Phylum, GoNiDioPHYTA. Zoospore Plants.

SYNOPSIS OF THE CLASSES OF GONIDIOPHYTA.

I. Plants unicellular or colonial, not truly filamentous.

A. Nonsexual, unicellular or colonial algae without zoospores, commonly
with autospores; cells normally with one nucleus. Autospor^.

B. Isogamous or heterogamous, sexual algas or probable derivatives from
them, with zoospores.

1. Unicellular or colonial algae, usually with one nucleus in each cell,
rarely cenocytic; the colonial forms not produced by the sym-
metrical aggregation of free zoospores into a definite colony;
vegetative stage nonmotile or active. Isogamus or heterogamous.
Chlorococce^e.

2. Cenocytic algae consisting of colonies of peculiar form, new colonies
being produced by the definite arrangement of daughter cells
developed in the parent cenocyte; isogamous, aquatic.

Hydrodictye^.
II. Green algas with a filamentous or massive body and with 1, 2, 4, or many
cilia on the zoospores and gametes.

A. Cenocytic, septate or nonseptate, isogamous or heterogamous.

1. Vegetative body usually septate, consisting of a series of cenocytes;
chloroplasts forming a net, rarely in separate plates. Siphonoclade^.

2. Vegetative body usually nonseptate, with distinct lenticular, oval or
plate-like chloroplasts. Siphone.^.

B. Algas having normal cells with one nucleus, with a conjugation of free
swimming gametes or with motile sperms and stationary eggs. CoNFERVEiE.

Class, Autospor^. 200 species.

I. Reproduction by autospores, the protoplast dividing within the mother cell,
and the daughter cells escaping singly or in colonies. In fresh, brackish, or
sea water, or on moist rocks, etc.; some endozoic in water animals. Sele-
nastrales. vSelenastracege, Oocystaceae, Chlorellaceas, Tetraedraceae, Scene-
desmaceae, Sorastraceae.
II. Reproduction by vegetative division and separation by splitting of the
daughter cells. (Doubtfully placed in the Autosporas). Aerial, on damp
stones, trees, etc., or in fresh or salt water. Protococcales. Protococcaceas.

Class, Chlorococce/E. 250 species.

I. Cells ciliated and motile in the vegetative state; unicellular or in definite
colonies. Volvocales. Chlamydomonadaceae, Volvocaceae.
II. Cells not active in the vegetative stage.

A. Vegetative cell divisions absent, cells separate or somewhat cenocytic.
Chlorococcales. Chlorococcaceae, Chloretheciaceae, Ophiocytiaceae.

B. Colonies increasing by vegetative cell division. Tetrasporales.
Botryococcaceae, Tetrasporaces.

Class, Hydrodictye.e. 30 species.
One order, Hydrodictyales. Pediastraceas, Hydrodictyaceas.

Class, S1PHONOCLADE.E. Lower Tube Algae. 450 species.

I. Plants isogamous or slightly heterogamous; filaments branched. Clado-
phorales. Valoniaceas, Cladophoraceae, Siphonocladacese, Dasycladaceae.
II. Plants heterogamous^ with stationary eggs and motile spermatozoids;
filaments septate,.unblfmched, free-floating. Sphaeropleales. Sphaeropleaceae.

Mar., 1922 classification of plants 133

Class, SiPHOXE.E. Higher Tube Algje. 200 species.

■ I. Sexual reproduction unknown or isogamous.

A. Small globular terrestrial plants with branched rhizoids penetrating the
ground; zoospores with cilia of unequal lengths.

Botrydiales. Botr\'diaceas.

B. Mostly large marine or sometimes endophytic algae; zoospores if present
not wnth unequal cilia. Bryopsidales. Derbesiacea^, Bryopsidaceae,
Caulerpace^, PhvUosiphonaceEe, Codiaceae.

XL Se.xual reproduction bV highly specialized stationary eggs and motile sperm-
atozoids; thallus tubular, branched or unbranched; growing in fresh or
brackish water or on moist soil. Vaucheriales. Vaucheriaceaj.

Class, CoNFERVE.^. Confervas. 650 species.

I. Isogamous, or the free-swimming gametes sometimes of unequal size.

A. Thallus unbranched.

1. Chloroplasts reticulate, without pyrenoids; fresh water plants.
Microsporales. Microsporaceae.

2. Chloroplasts central or parietal, with one or more pyrenoids. _

a. Chloroplast single, central, stellate, with one pyrenoid; no
zoospores known; aerial in habit. Prasiolales. Prasiolaces.

b. Chloroplast parietal, with one to many pyrenoids.

(a) Unbranched filaments; chloroplasts with one to many
pyrenoids. Ulotrichales. Ulotrichaceae, Tribonemacese.

(b) Thallus expanded, a 1-2-layered plane or tube; chloroplast
single, with 1 pyrenoid; mostly marine. Ulvales. Ulvaceae.

B. Thallus filamentous, branched, usually abundantly so, the branches
often attenuated or hair-like tips. Chaetophorales. Chaetophoraceae,
Trentepohliaceae, Harposteiraceae.

II. Heterogamous, the egg stationary in the oogonium; sometimes with a prim-
itive alternation of generations.

A. Oogonium not developing a cortical layer after fertilization. Oedogoniales.
Cylindrocapsaceae, Oedogoniaceas.

B. Oogonium with a trichogyne-like tip, covered after fertilization by a
cortical layer; thallus disk-like or cushion-like. Coleochaetales.
Coleochaetacese.

Phylum, Phaeophyta. Brown Algae.

I. Zoospores present; sexual reproduction by motile, biciliate gametes produced
ia external gametangia, occasionally by heterogametes, and in extreme cases
by nonmotile eggs. Class, Phaeospor.e. Kelps. 550 species.

A. Zoospores and isogametes similar and motile.

1. Frond various, simple or branched, but never differentiated w4th
definite root-like and leaf-like parts. Ectocarpales. Ectocarpacese.

2. Frond large, leather-like, usually stalked, differentiated with root-
like and leaf-like parts; with zoospores only. The largest marine
plants. Laminariales. Laminariacege. Giant Kelps.

B. Zoospores and heterogametes dissimilar.

1. Gametes large and small, but both motile. Cutleriales. Cutleriaceas.

2. Gametes consisting of small active spermatozoids and nonmotile
eggs; frond filiform. Tilopteridales. Tilopteridaceae.

II. Zoospores absent; sexual reproduction by means of motile sperms and non-
motile eggs which are discharged from the oogonium; nonsexual reproduction
absent or by means of nonmotile spores.

A. Sperms biciliate; without nonsexual spores; gametangia in sunken con-
ceptacles. Class, Cyclospor.^. Rockweeds. 350 species. One order
Fucales. Durvillaeaceae, Himanthaliaceag, Fucaceae, Sargassaceae.

B. Sperms with one flagellum; nonsexual spores nonmotile; reproductive
organs external; with a regular alternation of se.xual and nonsexual
generations. Class, Dictyote.e. 130 species. One Order, Dictyotales.
Dictyotaceae.

134 JOHN H. SCHAFFNER Vol. XXII, No. 5

Phylum, Rhodophyta. Red Algae.

I. Nonsexual reproduction by single thallus cells; trichogyne imperfectly
developed; no pits between the thallus cells. Class, Monospor^. 50 species.
One order, Bangiales. Bangiaceae, Rhodochaetaceae, Compsopogonacese.
II. Nonsexual reproduction by tetraspores usually developed in groups of four;
trichogyne well developed; cells protoplasmically connected through large
pits in the walls. Class, Floride^. 3000 species.

A. Sporophores ("gonimoblasts" or branches bearing the carpospores) of
the sporocarp produced directly from the fertilized oogonium; mostly
plants with filiform fronds. Fresh water or marine. Nemalionales.
Lemaneaceae, Helminthocladiaceas, Chaetangiaceae, Gelidiaceae.

B. Sporophores produced by auxiliary cells after these conjugate with the
fertilized oogonia or their branching processes ("ooblastema").

1. Sporophores produced by nearby auxiliary cells; marine plants.

a. Sporophores produced by nearby auxiliary cells and growing
outward in the plant body; filiform, foliaceous or massive plants.
Rhodymeniales. Sphaerococcaceje, Rhodymeniaceas, Deles-
sariaceae, Bonnemaisoniaceae, Rhodomelaceae, Ceramiaceae.

b. Sporophores produced by the nearby auxiliary cells and branch-
ing copiously in the surrounding tissues of the plant body; fronds
parenchymatous, flattened or leaf-like. Gigartinales. Acroty-
laceae, Gigartinaceas, Rhodophyllidaceae.

2. Sporophores produced by remote auxiliary cells after these have
conjugated with the branched "ooblastema" filaments arising from
the fertilized oogonium; fronds filiform, branched, often flattened.
Mostly marine, but a few fresh water species. Cryptonemiales.
Gloiosiphoniaceae, Grateloupiaceae, Dumontiaceas, Nemastomaceae.
Rhizophyllidaceae, Squamariaceae, Corallinaceae.

Phylum, Charophyta. Stoneworts.

One class and one order, Chare^e. "160 species. Charales.

I. Crown of the oogonium with ten cells. Nitellaceas.
II. Crown of the oogonium with five cells. Characeae.

KEY TO THF ORDERS OF ALG^

1. Nonsexual fission algse, unicellular, colonial or filamentous, blue-green or
brownish, never with a pure chlorophyll-green color, usually with gela-
tinous walls; filaments often with heterocysts; never with cilia or flagella,
but sometimes motile; chromotophores usually poorly defined. 2.

1. Mostly sexual algas, but sometimes nonsexual, with a pure chlorophyll-green

color or often red, purple, yellow, or brown; plants not propagating by
fission; tmicellular, colonial, filamentous, or massive; chloroplasts usually
well defined; commonly with zoospores; some with silicious walls. 6.

2. With poorly differentiated nuclei, without a definite nuclear membrane,

and with a low type of chromatophore. (Cyanophyce/E). 3.

2. With well developed nuclei, with a nuclear membrane, and with highly

differentiated chromatophores. (Glaucocyste^). Glaucocystales.

3. Not filamentous; tmicellular or colonial, free or attached. Chroococcales.

3. Cells arranged in definite filaments. 4.

4. Filaments without hair-like tips, sometimes narrowed at the ends. 5.

4. Filaments with hair-like tips at one or both ends, with or without hetero-

cysts. Rivulariales.

5. Without heterocysts. Oscillatoriales.

5. With heterocysts. Nostocales.

6. Cells covered with two silicious, usually ornamental valves, mostly brown or

yellowish in color; unicellular, or simple filaments, sometimes on gelatinous
stalks. (DiATOME^). 7.
6. Cells not covered with two silicious valves. 8.

Mar., 1922 classification of plants 135

7. Valves without a raphe or pseudo-raphe; usually with a concentric or radiating
symmetry around a central point, rarely isobilateral or zygomorphic;
valve view usually circular; polygonal, or broadly elliptical in outline.
Eupodiscales.

7. Valves with a raphe or pseudo-raphe, or with a sagittal line; with an isobi-

lateral or zygomorphic symmetry, never centric; valve view mostly boat-
shaped, needle-shaped, rod-shaped, or elliptic in outline. Naviculales.

8. Unicellular or simple free filaments, chlorophyll-green, with complex chro-

matophores containing prominent pyrenoids, reproduction usually by con-
jugation of the cell contents either through a conjugation tube or by the
breaking open of the cell walls; cells and gametes never with cilia;
unicellular forms usually of fantastic shapes, usually divided into two
symmetrical halves. (Conjug.at^). 9.

8. Sexual process if present by t^-pical isogametes, or heterogamous; plants

commonly branched filaments or massive, the unicellular forms or simple
filaments rarely corresponding to the above description. 10.

9. Thallus a filament or mostly unicellular, the cell wall usually divided into

two symmetrical halves, cells mostly constricted at the middle; con-
jugation by the breaking open of the cell walls or by the formation of a
primitive conjugation tube. Desmidiales.
9. Thallus a simple filament of cylindrical cells not constricted in the middle,
but sometimes the contents divided into symmetrical halves; these latter
forms distinguished from the preceding order by the definite filament
and the prominent conjugation tube. Zygnemales.
10. Antheridia when present not consisting of a globular structure containing
sperm-bearing filaments. 11.

10. Filamentous green algas with globular antheridia containing sperm-bearing

filaments, erect, branches in whorls; rhizoids thread-like; sperms biciliate,
non-sexual spores absent; plants more or less incrusted with lime.
(Ch.\re.«;). Charales.

—1 I'-
ll. Plants green, rarely with a red or brown color and then unicellular; nearly
all producing zoospores except the lowest; largely fresh water algae, but
some marine. 12.

11. Plants usually with the chlorophyll hidden by a brown, red, or purple pig-

ment, always with a multicellular body, often massive; sperms motile or
non-motile; mostly marine algas. 29.

12. Plants unicellular or colonial, not truly filamentous. 13.

12. Plants filamentous or massive. 18.

13. Nonsexual unicellular or colonial algae without zoospores, commonly with

autospores or merely splitting apart; cells normally with one nucleus, not
forming net-like or fantastic, radially symmetrical plate-like union colonies
(Autospor.'E). 1-4.

13. Isogamous or heterogamous sexual algae usually with zoospores. 15.

14. Reproduction by autospores, the protoplast dividing within the mother cell

and the daughter cells escaping singly or in colonies. Selenastrales.

14. Reproduction by vegetative division and separation by the splitting apart of

the daughter cells. Protococcales.

15. Unicellular or colonial algse with cells normally having one nucleus; the

colonial forms not produced by the symmetrical aggregation of free
zoospores. (Chlorococce.e). 16.

15. Cenocytic algae consisting of net-like or symmetrical plate-like colonies of

peculiar form, produced by the definite arrangement and union of daughter
cells in the parent cenocyte; (Hydrodictye.e). Hydrodictyales.

16. Cells ciliated and active in the vegetative state; unicellular or in definite

colonies, commonly spherical. Volvocales.

16. Cells not active in the vegetative stage. 17.

17. Vegetative cell division absent, cells separate or somewhat cenocytic.

Chlorococcales.
17. Colonies increasing by vegetative division. Tetrasporales.

136 JOHN H. SCHAFFNER Vol. XXII, No. 5

18. Cenocytic algse, septate or nonseptate. 19.

18. NotcenocytiCjbutwithnormalcellshavingasinglenucleus. (Conferve^). 23.

19. Vegetative body usually septate, consisting of a series of cenocytes; chloro-

plasts forming a net, rarely in separate plates. (Siphonoclade^). 20..

19. Vegetative body usually nonseptate, with distinct lenticular, oval, or plate-

like chloroplasts. (Siphone.«). 21.

20. Filanrents branched; plants isogamous. Cladophorales.

20. Filaments unbranched, free-fioating; plants heterogamous with stationary

eggs. Sphaeropleales.

21. Isogamous, or sexual reproduction unknown. 22.

21. Sexual reproduction by highly specialized stationary eggs and motile sperma-

tozoids; thallus tubular, branched or unbranched. Vaucheriales.

22. Small globular terrestrial plants with branched rhizoids penetrating the

ground; zoospores with cilia of unequal lengths or with only one.
Botrydiales.

22. Mostly large marine or sometimes endophytic algae; zoospores if present

otherwise. Bryopsidales.

23. Isogamous, or the free-swimming gametes of unequal size. 24.

23. Heterogamous, the egg stationary in the oogonium; oogonium developing a

cortical layer after fertilization, or if not then certain cells of the filament
with peculiar striate rings around the top. 28.

24. Thallus unbranched. 25.

24. Thallus filamentous, branched, usually abundantly so, the branches often

with hair-like attenuated tips. Chaetophorales.

25. Chloroplasts reticulate, without pyrenoids; growing in fresh water.

Microsporales.

25. Chloroplasts central or parietal, with one or more pyrenoids. 26.

26. Chloroplast single, central, stellate, with one pyrenoid; no zoospores known;

aerial in habit. Prasiolales.

26. Chloroplasts parietal with one to many pyrenoids. 27.

27. Unbranched filaments; chloroplasts with one to many pyrenoids. Ulotrichales.

27. Thallus expanded, a 1-2-layered lamina or tube; chloroplast single with one

pyrenoid; mostly marine plants. Ulvales.

28. Oogonium not developing a cortical layer after fertilization; zoospores with

a crown of cilia; certain cells with striate rings at the upper end.
Oedogoniales.
28. Oogonium with a trichogyne-like tip, covered after fertilization by a cortical
layer; thallus disk-like or cushion-like; zoospores biciliate. Coleochaetales.

29. Mostly marine brown algae; isogamous or with ciliated sperms, and large eggs,
both gametes discharged from the gametangia; or with zoospores only. 30.

29. Mostly marine red algae, with stationary eggs and non-ciliated sperms;

mostly with tetraspores; zoospores absent; usually with cj'stocarps. 35.

30. Zoospores present; sexual reproduction by motile biciliate gametes produced

in external gametangia; occasionally heterogamous, the extreme cases
with non-motile eggs. (Phaeospor.*:). 31.

30. Zoospores absent; sexual reproduction by means of motile sperms and non-

motile eggs which are discharged from the oogonium; gametangia sunken
or external; non-sexual reproduction absent or by means of nonmotile
spores. 84.

31. Zoospores and isogametes similar and motile. 32.

31. Zoospores and heterogametes dissimilar. 33.

32. Frond various, simple or branched, but never differentiated with definite

root-like and leaf-like parts. Ectocarpales.

32. Frond large, leather-like, usually stalked, differentiated with root-like and

leaf-like parts; with zoospores only; plants usually very large. Laminariales.

33. Gametes large and small but both motile; plants medium to large, fiat,

branched, or orbicular, attached by rhizoids. Cutleriales.
33. Gametes a small active spermatozoid and a nonmotile egg; fronds filiform,
tufted, attached by rhizoids. Tilopteridales.

Mar., 1922 classification of plants 137

34. Sperms biciliate; nonsexual spores absent; gametangia in sunken con-
ceptacles; plants usually flat or flattish, branched, attached below, medium
to large in size. (Cyclospor.^). Fucales.

34. Sperms with one flagellum, nonsexual spores (tetraspores) nonmotile, repro-

ductive organs external; fronds erect, flat, leaf-like, attached by rhizoids.
(Dictyqte.'E). Dictyotaies.

35. Nonsexual reproduction by single thallus cells, monospores; trichogyne

imperfectly developed; no pits between the thallus cells; plants red or
purple, mostly filamentous or sometimes stratose. (Moxospor/e) .
Bangiales.

35. Nonsexual reproduction by tetraspores, usually developed in groups of four;

trichogyne well developed; carpospores developed on filaments after
fertilization; cells' of the thallus protoplasmically connected through large
pits in the cell walls. (Floride^). 36.

36. Sporophores ("gonimoblasts" or branches bearing the carpospores) of the

sporocarp on the sexual plant produced directly from the fertilized
oogonium; mostly plants with a filiform frond; fresh water or marine.
Nemalionales.

36. Sporophores produced by auxiliary cells after these conjugate with the

fertilized oogonia or their branching processes ("oob.lastema"). 37.

37. Sporophores of the sexual plant produced by nearby auxiliary cells; marine

plants. 38.

37. Sporophores produced by remote auxiliary cells after these have conjugated

with the branched "ooblastema" filaments arising from the fertilized
oogonia; fronds filiform, branched, often flattened; mostly marine, but
a few fresh water species. Cr5T)tonemiales.

38. Sporophores produced by nearby auxiliary cells and growing outward in the

plant body; filiform, foliaceous, or massive plants. Rhodymeniales.
38. Sporophores produced by nearby auxiliary cells and branching copiously in
the surrounding tissues of the plant body; fronds parenchymarous, erect or
spreading, branching, cylindrical, flattened, or leaflike. Gigartinales.

Phyla, Subphyla, Classes and Subclasses
OF Plants.

A general table of the classification of the plant kingdom on
a phyletic basis is given below. At present the writer recognizes
50 classes, a class being defined as a group of plants in a sub-
kingdom or division whose members show an evident relation-
ship. A class may also be defined as the largest, definitely deter-
mined, monophyletic group in a subkingdom. A phylum con-
sists of one or more classes showing a probable relationship.
It might be mentioned that a subkingdom is one of the seven
progressive stages into which Hving plants may be divided, each
stage being separated from the next higher by a more or less
prominent hiatus.

Phylum I. ScHizoPHYTA. Fission Plants.

Class L Cyanophyceae. Blue-green Algae.
Class 2. Glaucocysteas. Higher Blue-green Algas.
Class 3. Schizomycetae. Fission Fungi.
Class 4. Myxoschizomycetae. Slime Bacteria.

138 JOHN H. SCHAFFNER Vol. XXII, No. 5

Phylum II. Myxophyta. Slime Fimgi.

Class 5. Plasmodiophoreae. Clubroot Fvingi.
Class 6. Acrasieae.

Class 7. Myxomycetae. Slime Molds.
Subclasses.

a. Ceratiomyxeae.

b. Myxogasterae.

Phylum III. Zygophyta. Conjugate Algae.

Class 8. Diatomeae. Diatoms. (Subphylum A).
Class 9. Conjugatae. Conjugates. (Subphylum B).

Phylum IV. Gonidiophyta. Zoospore Plaats.

Class 10. Autosporae.

Class 11. Archemycetae. Primitive Fungi.

Class 12. Chlorococceas. Green-slimes.

Class 13. Hydrodictyeae.

Class 14. Siphonocladeae. Lower Tube Algae.

Class 15. Siphoneae. Higher Tube Algae.

Class 16. Monoblepharideag.

Class 17. Conferveae. Confervas.

Phylum V. Phaeophyta. Brown Algae.
Class 18. Phaeosporae. Kelps.
Class 19. Cyclosporae. Rockweeds.
Class 20. Dictyoteae.

Phylum VI. Rhodophyta. Red Algae.
Class 21. Monosporae.
Class 22. Florideae. Red Seaweeds.

Phylum VII. Charophyta. Stoneworts.
Class 23. Chareae.

Phylum VIII. Mycophyta. True Fungi.
Subphyltmi A. Phycomycetae. Algal Fungi.
Class 24. Zygomycetae.
Class 25. Oomycetae.
Subphylum B. Mycomycetae. Higher Fungi.
Class 26. Ascomycetas. Sack Fungi.
Subclasses.

a. Hemiascae. Intermediate Sack Fungi.

b. Exoascae.

c. Aspergilleas. Tuber Fungi.

d. Discomycetae. Disk Fungi.

e. Pyrenomycetae. Black Fungi. "

f. Deuteromycetae. Imperfect Fungi.
Class 27. Laboulbenieae. Beetle Fungi.
Class 28. Teliosporse. Brand Fungi.

Class 29. Basidiomycetae. Basidium Fungi.
Subclasses.

a. Protobasidiae.

b. Hymenomycetse.

c. Gasteromycetae.

Phylum IX. Bryophyta. Mossworts,

Class 30. Hepaticae. Liverworts.

Class 31. Sphagneas. Bog Mosses.

Class 32. Schizocarpge. Granite Mosses.

Class 33. Musci. True Mosses.

Class 34. Anthocerotae. Hornworts.

Mar., 1922 classification of plants 139

Phylum X. Ptenophyta. Femworts.
Class 35. Filices. Ferns.
Subclasses.

a. Eusporangiatae. Primitive Ferns.

b. Leptosporangiatae. Modem Ferns.
Class 36. Hydropteridae. Water-ferns.
Class 37. Isoeteae. Quillworts.

Phylum XI. Calamophyt,\. Calamite Plants.

Class 38. Sphenophylleae. (Fossil). Wedge-leaf Calamites.

Class 39. Equiseteae. Horsetails.

Class 40. Calamariae. (Fossil). Calamites.

Phylum XII. Lepidophyta. Scale-leaf Plants.
Class 41. Lycopodieae. Lycopods.
Class 42. Selaginelleas. Selaginellas.

Phylum XIII. Cycadophyta. Cycad Plants.

Class 43. Pteridospermae (Fossil). Seed Ferns.
Class 44. Cycadeae. Cycads.
Class 45. Cordaiteae (Fossil). Cordaites.
Class 46. Ginkgoae. Maiden-hair-trees.

Phylum XIV. Strobilophyta. Strobilus Plants.
Class 47. Coniferae. Conifers.
Class 48. Gneteae. Joint-firs.

Phylum XV. Anthophyta. Flowering Plants.
Class 49. Monocotylae. Monocotyls.
Subclasses.

a. Helobiae.

b. Spadiciflors.

c. Glumifiorae.

d. Liliifiorae.

Class 50. Dicotylae. Dicotyls.
Subclasses.

a. Thalamiflorae.

b. Centrospermae.

c. Calyciflorae.

d. Amentiferae.

e. Myrtiflorae.

f. Heteromerae.

g. Tubiflorae.
h. Inferae.

A NEW HYMENOPTEROUS PARASITE UPON ADULT

BEETLES.

A. B. GAHAN

Branch of Cereal, and Forage Crop Insects, Bureau of Entomology,
U. S. Department of Agriculture

The writer has recently received from Mr. W. V. Balduf,
Assistant Entomologist of the Ohio Agricultural Experiment
Station and graduate student at Ohio State University, speci-
mens of an interesting parasite, which appears to be new to
science. This parasite is interesting not only because it attacks
a well known garden pest, the cucumber beetle {Diabrotica
vittata), but it is interesting also structurally and biologically.

The writer is indebted to Mr. Balduf for the following
facts regarding its life history : The parasite attacks the adult
beetle by mounting on the back of its host and thrusting its
ovipositor into the thorax, apparently through one of the
sutures near the base of the elytra, and depositing its egg
within. The parasite larva feeds internally. In its earlier
stages it has a sort of tail like terminal appendage which is lost
before maturity. The mature larva escapes from the body of
its host either at the junction of head and thorax or of the
thorax and abdomen, and although the host is not outwardly
defaced, it is killed. The parasite larva undergoes its trans-
formation just below the surface of the soil in a closely woven
silken cocoon. Pupation lasts approximately ten days. The
parasite is not plentiful, having been found in an average of
about one or two beetles per hundred late in the summer and
somewhat more commonly in May and June.

In its mode of development the parasite reminds one of the
common parasite of lady-bird beetles [Dmocampus terminalis
Nees], but differs in many important details. It is perhaps
more nearly like Perilitus eleodis Viereck, but here again there
are marked differences in details, such as the manner and place
of oviposition, the place of emergence from the host, and the
method of pupation.

Following is a description of the adult female parasite:

140

Mar., 1922 new hymenopterous parasite 141

Superfamily Ichneumonoidea.

Family Braconid^.

Subfamily Liophronin.e.

Syrrhizus diahroticce, new species.

This species does not fully agree with the characterization
of the genus Syrrhizus Foerster, which is said to have the first
cubital and first discoidal cells confluent and the notauli
entirely effaced. In the present species the first abscissa of
cubitus is only partially obsolete and the notauli are not com-
pletely effaced, being represented by a short groove at each
lateral anterior angle and a deep dimple-like median fovea or
depression near the posterior margin of the mesoscutum.
It is apparently intermediate between Syrrhizus on the one hand
and both Centistes Haliday and Leiophron Nees on the other,
but agrees better with the former than with either of the latter.
Considering the evident intergradation of the characters cited,
it seems more reasonable to place it in Syrrhizus than to erect
a new genus for it at this time.

Female. — Length 2.2 mm. Head viewed from above transverse, a
little more than one and one-half times as broad as long, flattened in
front and rounded behind, the occipital carina complete and far below
the vertex; frons, vertex, occiput and posterior orbits smooth and
polished; viewed from in front the head is very slightly broader than
high, subtriangular in outline, convexly rounded above and subtruncate
below; inner margins of the eyes nearly parallel, a little divergent
below; malar space slightly shorter than the width of mandible at
base; face hairy and shining, with a longitudinal swelling medially,
and very finely and obscurely punctate laterad of the median ridge;
antennae inserted a little above the middle, 24-jointed, the basal joints
approximately three times as long as broad, apical joints about twice as
long as broad; mesoscutum perfectly smooth and polished, with the
notauli effaced except for a short groove at each lateral anterior angle
and a deep median fovea near the posterior margin; disk of scutellum
smooth and small, with the transverse groove between it and the mesos-
cutum very broad and divided in the middle by a single longitudinal
carina; lateral face of scutellum strongly rugose; metanotum longitudi-
nally striate ; propodeum rugulose except at anterior middle, with a median
longitudinal carina on the anterior half and a distinct transverse carina
extending completely across the sclerite a little behind the middle, the
posterior face with several irregular longitudinal raised lines; spiracles
small and round; mesopleura mostly smooth with the groove shallow
and more or less weakly foveolate or rugulose; stigma of forewing

142 A. B. GAHAN Vol. XXII, No. 5

broad; first abscissa of radius not half as long as the width of stigma,
the second abscissa long and curved, not reaching to the wing apex;
metacarpus a little longer than the anterior margin of stigma; basal
half of first abscissa of cubitus effaced, the first cubital and first dis-
coidal cells incompletely confluent; cubital vein beyond the inter-
cubitus obsolescent; nervulus postfurcal by nearly its own length;
first brachial cell narrowly open at its posterior outer angle; abdomen
subequal to the thorax in length, curved downward at apex; first
tergite increasing gradually in width from base to apex, longitudinally
striate, about twice as broad at apex as at base and a little more than
one and one-half times as long as broad at apex; second and following
tergites perfectly smooth, the second large and occupying most of the
dorsal length of abdomen, tergites beyond the second bent downward;
ovipositor curved sharply downward and forward, the ovipositor
sheaths broad, narrowed at base and apex and a little shorter than the
length of first tergite,

Black; five or six basal joints of antennae, mandibles, clypeus, palpi,
and all legs including their coxae pale reddish testaceous; face, pro-
thorax and the mesopleura more or less reddish brown to piceous ; tarsal
claws, and antennas except base of latter dark brown; wings hyaline,
stigma and veins dark brown except medius and submedius which
are pale; ovipositor testaceous, its sheaths black.

Male unknown.

Type locality. — Marietta, Ohio.

Type.— Cat. No. 25064, U. S. N. M.

Host. — Diahrotica vittata (Fabricius).

Type and three paratype females received from W. V.
Balduf, of the Ohio Agricultural Experiment Station, by whom
they were reared June 29 and July 2, 1921, from adults of the
cucumber beetle.

DESCRIPTIONS OF ALASKAN DIPTERA OF THE
FAMILY SYRPHID^.

JAMES S. HINE
Department of Zoology and Entomology, Ohio State University

All of the species treated in this paper except Sericomia
cynoctphala were collected by the Katmai Expeditions of the
National Geographic Society. Full accounts of the insect
collections of these expeditions are being prepared for pubhcation,
but as it is desired to refer to some of the species in other papers
these descriptions are published in advance of the final report.

Chilosia platycera n. sp.

Male and female shining black. General form of the body elongate
and rather slender. Vestiture of the body mostly pale, scutellum with
a marginal row of slender black bristles, eyes naked, antennse yellow,
aristce dark, naked; legs largely black, apex of each femur yellow,
tibiffl and tarsi partially yellow; wings pale yellowish hyaline. Length
5-7 mm.

Female: Eyes bare, face and front shining black, front largely pale
pilose, but with a few black hairs intermixed, face below the antennae
concave, facial tubercle rather prominent, much nearer the mouth than
to the base of the antennae. Antenna wholly yellow, arista dark, nearly
black, bare, third segment unusually large, only slightly longer than
wide. Thorax wholly shining black with short, pale, pile rather sparsely
distributed. Scutellum with a few slender marginal bristles. Wings
pale yellowish hyaline, halteres and squamae pale, nearly white; legs in
large part black, narrow apex of each femur, base and apex of each tibia
and second, third and fourth tarsal segments on all the feet yellow.
Abdomen shining black all over, pilosity short and pale grayish in color.

Male: Colored like the female, frontal triangle with long black pile,
antennae yellow, third segment decidedly smaller than in the female,
pilosity of the body rather long and conspicuous, especially along the
side margins of the abdomen, abdomen entirely shining, slenderer than
in the other sex.

Female type, Katmai, Alaska, July, 1917. Allotype with
the same data. Paratypes, 12 females and 3 males from the
same locahty taken in June and July, 1917, and one female
from Savanosky, Naknek Lake, Alaska, July, 1919. Type in
the Ohio State University Collection.

143

144 JAMES S. HINE Vol. XXII, No. 5

Chilosia rohusta n. sp.

Male and female shining black and conspicuously pale pilose all
over. Scutellum without bristles which are differentiated from the
rather dense covering of pile. Eyes conspicuously long hairy; antenna
yellow, arista dark colored, naked; wing yellowish hyaline, somewhat
darker along the costa; legs largely black, tibiae partly yellow. Vesti-
ture over the whole body conspicuously pale yellowish in color, occa-
sionally varying to golden especially in the female. Form robust.
Length 9-12 mm.

Female: Front nearly as wide as either eye, shining black, pale
pilose; face shining black concave below the antennae, facial tubercle
large and located somewhat nearer the oral margin than the base of
the antennse. Antenna yellow, first two segments partially brown,
third segment about as long as broad. Femora black, yellow at extreme
apex of each, tibiae partially yellow, median third or more of each,
brown to black, all the tarsi almost wholly dark colored with short
golden pile beneath. Wing yellowish hyaline, darkest in costal region
of basal half, veins brown, squamae and halteres pale.

Male: Colored like the female except the body pile tends toward
paler in the specimens studied. Abdomen entirely shining as in the
female, and somewhat more slender than in that sex.

Differs from lasiopthalma as follows : The face is much less produced
in both sexes making the distance between the base of the antennas
and the apex of the facial tubercle much shorter than in lasiopthalma,
the pilosity of the eyes is paler and shorter and the wings are less infus-
cated.

Female type, Kodiak, Alaska, June, 1917. Allotype has
the same data. Parotypes, five males and ten females with
the same data as the type; seven males and fourteen females,
Katmai, Alaska, July, 1917; five males and one female. Snug
Harbor, Alaska, June, 1919.

Type in the Ohio State University Collection.

Syrphiis atteyiiiatus n. sp.

Male and female. Face yellow, without a black stripe, lower part of
front including the insertion of the antennae yellow, antenna largely
reddish, third segment dark above, arista dark, eyes naked, occiput
dark in ground color but largely hidden by a covering of yellowish gray
pollen. Thorax dull blue black in ground color, scutellum rather bright
yellow, entire thorax clothed rather densely with long yellow pile,
wings hyaline, costal cells opaque' yellowish; "abdomen black 'with three
pairs of spots and apex yellow, 'first pair iof spots on Second segment
somewhat smaller than the other 'two p3;irs; tri&,ngular, with the long;
side anterior, outer angle produced over the, abdominal margin, second
pair of spots on the third segmeiit, oblong, 'slightly concave anteriorly
and convex posteriorly, outer angle very narrowly produced but scarcely

Mar., 1922 alaskan diptera of the family syrphid^ 145

reaching the lateral margin, third pair of spots on the fourth segment
similar to those on the third, outer angle produced very narrowly over
the margin, posterior margin of fourth segment, anterior and posterior
margins of fifth segment and all of sixth segment, yellow. Length,
11 to 13 mm.

Female: Front black on the u]jper three-fourths, the lower half of
the black color yellowish pollinose, less densely so at middle, front
black pilose, pilosity continuing below the antennae on either side next
the eyes, much of the face sparsely yellow pilose; all the legs yellow to
the bases of the femora, coxas and trochanters dark, posterior feet pale
brownish. All the abdominal spots much attenuated and reaching over
the abdominal margins, fifth segment yellow with a curved black band
about half the width of the segment.

Male: Vertical triangle black and black pilose, frontal triangle
black on superior half and entirely black pilose, pilosity extending much
below the antennas at the sides next the eyes; cheeks blackish beneath
the eyes, margin of the mouth behind yellow; legs to the basal fourth
of the femora, black, otherwise yellow with the exception of the tibiae
which are partially brown, the hind ones nearly black. Fifth abdominal
segment yellow with a very narrow median black marking. Genital
segment all yellow.

Male type taken at Savonosky, Naknek Lake, Alaska,
July, 1919. Allotype with the same data. Paratypes, ten
males and seven females with the same data, a male from the
same locality taken in August and a female from Katmai,
Alaska, 1917. In the Ohio State University Collection.

The species varies somewhat. In some specimens the
abdominal spots are larger and reach the lateral margins
plainly and at greater width than in the type. In one specimen
the narrow outer margin of the abdomen is all yellow and the
black marking on the fifth abdominal segment varies in size
and shape in different individuals. Sometimes the hind
femora of the male practically entirely yellow. The pair of
spots on the fourth abdominal segment is connected occasionally
at the anterior inner corners, forming a band which is very
deeply notched posteriorly. It is a large robust species,
easily separated from others of its size by abdominal markings.

Syrphus curtiis n. sp.
Male and female: Eyes naked, cheeks, mouth margin and facial
stripe extending upward just over the tubercle, black; remainder of
face yellow. Antenna largely black, only the inferior margin of the
third segment reddish. Thorax yellow pilose, scutellum pale; wings
hyaline. Abdomen with three pairs of yellow spots entirely separated
from the margins of the segments, posterior margins of fourth and fifth

146 JAMES S. HINE Vol. XXII, No. 5

segments and anterior outer comers of fifth segment also yellow.
Length 8-9 millimeters.

Female: Front black on upper two-thirds, otherwise yellow with the
exception of a narrow crescent shaped mark above each antenna which
is dark brown, entirely black pilose. Yellow abdominal spots concave
anteriorly and convex posteriorly making them somewhat kidney
shaped with the outer anterior corner somewhat produced and pointed ;
the spots on the second segment are smaller and more transverse than
the others with the inner ends evenly rounded; legs largely yellow,
black to the basal fourth or fifth of the front and middle femora and to
a greater extent on the hind femora. Hind tibias with dark areas and
all the tarsi dark in part.

Male: Vertical triangle black, frontal triangle yellow with black
pile. Abdominal spots similar to those of the female, but those on the
third and fourth segments quite distinctly larger; legs colored similarly
to those of the other sex but black of the femora more extensive,
including nearl}^ half of middle and front pairs and two-thirds or more
of hind pair.

Female type, Savanoski, Naknek Lake, Alaska, August,
1919. Allotype with the same data. Parotypes, six males
and one female from Savanoski, Naknek Lake, Alaska, 1919,
and ten females from Katmai, Alaska, 1917. Type in the Ohio
State University Collection.

The coloration of the legs is somewhat variable in the
species, being darker in general in some specimens, and the black
of the femora is more extensive in some specimens than others,
especially is this true of the females. The extent of the black
on the lower part of the front of the female varies somewhat
and the dark crescent-shaped marking above the base of each
antenna is more pronounced in some specimens than in others.

Syrphiis limatus n. sp.

Male and female shining blue black, face with a wide, shining black
stripe, wider than the yellow on either side of it, pointed above and
reaching nearly to the base of the antennas; cheeks shining black, eyes
rather sparsely hairy, antennas black, abdomen with three pairs of
narrow spots, first pair small and located near the middle of the second
abdominal segment and entirely separated from the margins, second
pair near the anterior margin of the third segment very slightly oblique
and extending toward the middorsal line but not quite reaching it, inner
third of the spot somewhat widened and nearly touching the anterior
margin, outer end reaching over the lateral margin in full width; third
pair of spots similar to the second, but narrower, located near the
anterior margin of the fourth segment; narrow posterior margins of
fourth and fifth segments and anterior lateral comers of the fourth
segment also yellow. Length 10-11 mm.

Mar., 1922 alaskan dipteka of the family syrphid^ 147

Female: Front shinino; black to the base of the antennee, black
pilose, with an irregular pollinose band reaching from eye to_ eye above
the antennae, this pollinose band is briefly interrupted at its middle.
The yellow on each side of the face unites around the upper end of the
black middle part and sends a projection up between the antennae.
Thorax shining black, scutellum dark brown; wing hyaline, stigma
opaque black, space between first and second veins slightly infuscated
back to the wing base; legs partly black, outer half of front and middle-
femora and apex of hind femur light brown; all tibiae in large part
brown, tarsi dark, nearly black.

Male: Very near to the female in size and coloration. The hind legs
are more extensively black in this sex and the pilosity of the eyes is
more pronounced.

Type in the Ohio State University Collection.

This species is somewhat like creper and paiixillus. It is
larger than either and differs in having a much more extensive
black marking on the face. The abdominal markings on the
third and fourth segments extend over the lateral margins in
which respect it agrees with venustus of Europe.

Sericomyia cynocephaJa n. sp.

Female: Face much produced, so that the distance from the base
of the antennae to the apex of the facial production is nearly twice the
distance from the base of the antennae to the vertex. Face uniformly
yellow, lacking the black stripe commonly present in other members of
the genus ; cheeks from the anterior comer of the eye to the apex of the
facial production shining black; front black, sparsely gray pollinose
and black pilose; antenna black, third segment about as wide as long
and very slightly reddish at base, arista black and long plumose;
posterior orbits yellowish pilose. Thorax black in ground color, scu-
tellum pale brown, whole thorax yellowish pilose; wing hyaline, veins
mostly pale, stigma .yellow, squamae pale with a pale fringe, ballancers
yellow; legs black, tips of femora, less pronounced on the hind pair,
and bases of tibiae yellow. Ground color of abdomen above and below
black, segments two, three, and four above each with a pair of oblique
elongate yellow spots. All of these spots are widened outwardly and
none of them reach any of the margins of their respective segments;
spots on the second segment widely interrupted, those on the other
segments more narrowly interrupted. Length 14 millimeters.

Female type collected by V. Stefansson at Barrow, Alaska,
spring of 1912. Type in the American Museum of Natural
History.

This species is distinct from all the species of Sericomyia
known to me by the extreme production of the face and the
absence of the black facial stripe. In the other species of the
genus^I^have^^ studied the facial tubercle is pronounced, but in
cynocephalathis tubercle is only feebly indicated.

THE ZOOLOGICAL RECORD

1 Feb., 1922.
The Editor, Ohio Journal of Science:

Dear Sir: I should be glad if you would draw the attention of
your readers to the present position of the Zoological Record.

Owing to the collapse of the International Catalogue of Scientific
Literature in connection with which the Record was published from
1906 to 1914 the Zoological Society of London has undertaken to bear
the whole financial responsibility for the preparation and printing of
the Record.

Owing to the great increase of the cost of printing and to the very
meagre support accorded to the Record by Zoologists and Zoological
Institutes generally, the financial burden of this undertaking on the
Zoological Society is becoming very severe. The cost of printing the
Record now amounts to between 1500^ and 2000;^ annually and
the Society receives back by subscribers and sales less than 25% of
this s\xn\; I fear therefore, unless Zoologists are prepared to make
greater efforts to support the undertaking, there is a strong possibility
that the Council of the Zoological Society may refuse to find this
large sum each year.

It appears therefore, to be the duty of every Zoologist to help so
far as he is able to support this most invaluable work. All particulars
and forms of subscription can be obtained from the Secretary of the
Zoological Society, Regents Park, London N. W. 8., but I may mention
that the price of the whole volume is now 2 pounds, 10 shillings and the
price of the separate parts a proportional smaller sum.

Yours faithfully,

V. L. SCLATER,

{Zoological Society of London).

148

The Ohio Journal of Science

Vol. XXII April, 1922 No. 6

THE SEXUAL NATURE OF VEGETATIVE
OR DICHOTOMOUS TWINS OF ARIS^MA.*

JOHN H. SCHAFFNER

Department of Botany. Ohio State University

While studying sex reversal in Arisaema triphyllum (L.)
Torr., the writer accidentally came across some interesting
examples of dichotomous twins which have a bearing on the
theory of sex determination. Twin flower clusters were reported
several years ago by Pickettf who discovered about a dozen
of such plants. He says the two flower clusters were surrounded
by two leaves, and also makes the casual remark that the two
clusters "are of the same sex on each plant and are entirely
independent, arising from two separate initial groups."

The twin shoots and separated twins must not be confused
with the normal lateral buds, which are produced each season
from the corm. The main corm often becomes smaller, not
only from accidents to the aerial shoots and poor growing
seasons which reduce the available food supply but also from
excessive or vigorous lateral bud production. In case of
dichotomy of the growing bud which results in twins, one can
find all gradations from simple inflorescences with slightly flat-
tened spadices ending in two tips and with a double-pointed
spathe to individuals which have two entirely distinct aerial
shoots, identical in appearance and situated closely side by side.
Such pairs of twin shoots become entirely separated after a
year or more because of the further development of the two
buds and the dying off of the back end of the corm. The twins
can often be recognized as such for several years after com-

* Papers from the Department of Botany,. The Ohio vState University, Xo. 134.
t Pickett, F. L. A Contribution to our Knowledge of Arisaema triphvllum.
Mem. Torr. Bot. Club. 16:48. 1915.

149

150 JOHN H. SCHAFFNER Vol. XXII, No. 6

plete separation, both because of their position in the ground,
close together and with the buds pointing in the same direction,
and because of the remarkable similarity of the vegetative
characters and similarity in size. Occasionally there is a dif-
ference in size of the individuals, or in the length of the sterile
tips of the spadices, or in the time of emergence from the
ground. There is no reason why such differences should not be
decided, since the original fission of the bud may be quite
unequal. In the dichotomous branches of Vernonia baldwinii
Torr. and V. altissima Nutt,, for example, there is frequently a
decided difference in the length and complexity of the two forks.*
There might also be a difference in the more specific vegetative
characters occasionally, for the same reason that the two sides
of a symmetrically bilateral body may differ in the characters
expressed as, for example, the differences in the details of vena-
tion of pairs of insect wings, differences in the lobings of the
two halves of a leaf, differences in the colored spots of the heads
of certain turtles which are usually symmetrical, and differences
in the color of the eyes of dogs and men, where one occasionally
finds individuals with one eye blue and the other brown. The
same differences of expression must take place occasionally
after separation of two bilateral halves of an egg or vegetative
bud and it is, therefore, possible that identical twins may differ
decidedly in very important characters.

Not only are the Arisfema twins, so far discovered, all
remarkably alike in vegetative characters but they are of the
same sex. Some are staminate pairs, some are carpellate, and
some intermediate with both staminate and carpellate flowers
on the spadix, just as is the case with normal individuals. But
the most remarkable characteristic exhibited by the bisporan-
giate twins is that so far they have been identical or nearly
identical in the distribution, position, and numbers of the
staminate and carpellate flowers. Since the elaboration of the
hypothesis of the Mendelian nature of sex, it has been supposed
by some that the fact that identical or duplicate twins are
apparently always of the same sex gave a very strong pre-
sumption in favor of the correctness of the chromosome-linked
or Mendelian hypothesis. This is, however, not at all the case
as will appear from the evidence given below, derived from a

* ScHAFFNER, JoHN H. Unusual Dichotomous Branching in Vernonia. Ohio
Jour. Sci. 19:487-490. 1919,

April, 1922 SEXUAL nature of twins of aris.^ma 151

study of a considerable number of twins of Arisaema, when it is
remembered that sex in Arisaema has nothing to do primarily
with chromosome shiftings and can be controlled and reversed
almost completely by environmental means.

CHARACTERIZATION OF TYPICAL EXAMPLES.

1. A plant with twin leaves on a common petiole and twdn
spadices on a common peduncle. The two leaves each had
three leaflets and had short petioles coming from the common
petiole. The spathe had tw^o points and surrounded the tw^o
spadices. Both spadices were pure carpellate and the sterile
tips both had the upper two-fifths colored dark purple.

2. Twin shoots coming from the same corm. They were
alike in size and general appearance. Both had the sterile tip
purple. Both had identical sexual expression, being monecious
with a zone of carpellate flowers below, covering about three-
fifths of the spadix, and with a staminate zone above. Both
inflorescences had purple-red anthers and greenish white
stigmas.

3. A pair of large twins with separate corms but evidently
just recently divided — probably the preceding summer. Both
were very late in coming out of the ground; both had green
spathes and green sterile tips; and both were pure carpellate
with violet stigmas.

4. A pair of small twins with distinct corms but still close
together. Both had green spathes and green sterile tips. Both
were pure carpellate. One plant was 8 in. tall and the other
73^ in.

5. Large separated twins, both 12 in. tall to the tip of the
spathe. The spathes of both were a uniform dark purple at the
tip on the inside, and purple and greenish-white striped below.
The sterile tips of both were dark purple above, purple spotted
in the middle part, and green below. The sterile narrow stalks
of the sterile tips were both purple spotted. Both were pure
carpellate with pale violet stigmas.

6. A pair of twins just separated and situated close together.
Both were 6}/^ in. tall to the top of the sterile tip; both had one
larger and one smaller leaf; both had the spathes striped above,
broad purple stripes alternating with narrow greenish -white
stripes, and uniform greenish-white below. Both had the

152 JOHN H. SCHAFFNER Vol. XXII, No. 6

sterile parts of the spadices purple mottled at the tip, with a
solid band of purple just above the middle, and with a slight
purple spotting below, extending from the purple band to the
base of the sterile stalks. Both inflorescences were carpellate on
the main part of the spadix with purple stigmas; and on the
stalks of the sterile tips, a little way above the carpellate inflor-
escence, both had four purple-anthered staminate flowers!
There was a slight difference between the two inflorescences in
that one had a small, additional staminate flower in the top of
the carpellate part, in addition to the four staminate flowers
further up.

7. A pair of separated twins with green sterile tips but
with their short stalks above the flower-bearing part slightly
purple mottled. The spathes had green tips with purple stripes
on their sheaths below. Both plants were robust. One was 12 in.
tall to the top of the sterile spadix and the other was 11 in.
Both were pure carpellate.

8. A pair of twins still united on the same corm. They were
remarkably alike but one was slightly taller than the other,
measuring l}/2 in. while the other measured 73^ in. Both had
the sterile spadices or tips expanding decidedly toward the
base. The tips were purple mottled while the bases were pure
green. The spathes were greenish on the outside ; but each had
a broad band of purple on the inner side, one on the right side
and the other on the left . The opposite sides of the spathes had
a narrower purple mottled band, while the center of each was
green slightly mottled with purple. The spathes, therefore,
showed a decided right and left symmetry. The sheaths of the
spathes were both folded clockwise, but this is a fluctuating
character. Both inflorescences were pure staminate.

9. A pair of twins which developed in the writers exper-
imental plots. The original plant was a pure carpellate individ-
ual brought in from the woods with others for experiments on
sex reversal. This individual was treated for reversal to the
male state by having its root system and leaves greatly reduced
and being kept in a comparatively dry condition. The following
year the growing bud showed that dichotomy had taken place,
as the corm developed twin shoots. Both branches were pure
staminate, being completely reversed in sex, along with a sim-
ilar change in most of the other individuals in the plot that had
been treated in the same way. The twins were of equal size and

April, 1922 sexual nature of twins of aris^ma 153

character and developed at the same time. The plot containing
the twins w^as then treated for reversal to the female state by
an application of rich cow^ manure and abundant w^ater supply
during the entire spring and summer. The follow^ing spring
(1921) the twins had both reversed their sex completely and
were now- pure carpellate again. Examination of the under-
ground parts showed that the corms had separated, although
with the dead part still united. The twins were now of unequal
size and one was nearly a week earlier in coming out of the
ground than the other.

AriscBma dracontiiim (L.) Schott.

Some observations and experiments were also made on the
green-dragon. This species consists of normal monecious and
staminate individuals with occasional abnormal intermediates.

10. A plant with dichotomous inflorescens. The spathe
ended in two separate points, the free points being one inch
long. The spadix was double but united except near the tips of
the sterile part. The entire double spadix was staminate. One
of the free sterile tips was five-eighths inch long and the other
seven-eighths inch. There was also some difference in thickness.

11. A simple staminate plant was transplanted from the
woods with others in 1920 and treated for continuation of the
staminate condition. In 1921 it gave rise by dichotomy to
identical staminate twans.

12. A pair of tall, robust twdns that looked like monecious
individuals, but both stalks were completely sterile, each hav-
ing a small, abortive structure where the infiorescencs should
have developed. They were still united on a single very large
corm. This corm was transferred to the experimental plots in
1920 and treated for reversal to the staminate condition by
reducing the root system and leaf surface decidedly. In the
spring of 1921 both came up as pure staminate shoots. One
came out of the ground a week earlier than the other.

CONCLUSIONS.

All of the twdn Arisasmas described above show-ed a remark-
able similarity in vegetative characters and w^ere exactly alike
in sexual expression. Since it has been established that the
sexual state of Arisaema can be changed at will by proper

154 JOHN H. SCHAFFNER Vol. XXII, No. 6

treatment,* it becomes evident that identity of sex in duplicate
twins can ?wt be regarded as giving any conclusive evidence in
support of the hypothesis that sex is determined by Mendelian
factors. As shown in the examples of twins described above in
Numbers 9 and 12, the sex of twins has been completely reversed
and the reversal was identical for each twin of a pair. The
intermediate examples are even more striking than those with
pure sexual expression. Cases like the one described under
Number 6 must certainly be regarded as most remarkable in
view of the fact that the sex of the individual is so easily
changed. All these cases show that the nutritive balance or
whatever it is that determines the sexual state must act with
decided precision when individuals of like heredity develop
under like conditions. Although so far the writer has no evi-
dence that Arissema twins placed in different environments
would develop the opposite sexual states in any given season,
yet, in view of the fact that any ordinary individual can be
changed from season to season and that the pairs of twins have
actually reversed their sex to the opposite state in agreement
with a change in nutritive environment, it appears that such
must be the case.

As shown by the examples listed above, certain pairs of
dichotomous twins show fluctuation of a considerable degree,
but so far this has been found mainly for size, folding of the
spathe, emergence from the ground, and the like. The varietal
characters, like coloring of the spadix and spathe, shape of the
sterile spadix and length of its stalk, shape of leaflets, color of
anthers and stigmas, etc., are remarkably alike in each pair and
deviate only in minute detail.

* ScHAFFNER, JoHN H. Control of the Sexual State in Arisaema triphyllum
and Arisaema dracontium. Am. Jour. Bot. 9: 72-78. 1922.

EMERGENCE OF A MAYFLY FROM ITS
NYMPHAL SKIN.*

F. H. KRECKER
Department of Zoology and Entomology, Ohio State University

The emergence of a subimago mayfly from its nymphal
skin observed by Superintendent George F. Miller and Captain
Bickford, both of the Ohio State Fish Hatchery at Put-in-Bay,
Ohio, and later described to me by them, impressed me as
being of sufficient interest to warrant the addition of one more
account to the number that have already been published
regarding the subject of mayfly emergence.

The transformation occurred in a large, portable fish tank
which had been standing for a number of weeks on the dock
in front of the Hatchery building. This tank had been filled
with water from the lake by means of a steam pump which
had its intake lying very near the bottom and, presumably,
the mayfly nymph had been drawn up with the water. Mr.
Miller and Captain Bickford were standing at the side of the
tank and were thus in an unusually fortunate position for
observing the entire process of emergence. It occurred some-
time during the month of June. The nymph swam upward
from the bottom of the tank and when it reached a point about
six inches beneath the surface of the water the nymphal skin
split along its dorsal surface and the subimago began to push
out. By the time it had reached the surface the subimago had
freed itself entirely from the nymphal skin and was able to
fly away immediately.

Neither of the men was familiar with the names of ephemerid
species or the criteria for distinguishing them and therefore
it is impossible to say to which one this individual belonged.
The species which occur most commonly in the region of
Put-in-Bay during the late spring and early summer are
Hexagenia bilineata and Ephemera simulans.

Needham ('18) describes the emergence of Hexagenia
bilineata as follows: "Transformation occurs at the surface

Papers from the Lake Laboratory, Ohio State University, No. 74.

155

156 r. 11. KRECKER Vol. XXII, No. 6

of the water and usually at night. The grown nymph swims
up and floats. A rent appears in the skin of its back. The
subimago suddenly emerges from this rent, its wings expanding
almost full size instantly. It stands a moment on the surface
and then rises and flies away to the shore." Heptagenia was
seen emerging under laboratory conditions by Clemens. He
says, "they were observed to crawl up sticks placed in the
breeding jar for the purpose and transform just above the
water-level. "

Some species are apparently able to adapt themselves to
varying conditions, as is shown by their ability either to crawl
up some solid support or else arise directly from the surface
of the water. This is the case in Chirotenetes albomanicatus as
described by Miss Morgan. She writes: "They crawl up
on the shore, leaving their cast skins clinging to the stones or
less often they flew up directly from the mid-current. " Need-
ham's ('05) statement regarding the same species: "Trans-
formation takes place at the surface of the water as in other
species," was made some years before Miss Morgan published
her observations. It is merely an example of the fact that our
knowledge of habits is subject to modification and it leaves
open the possibility that the case I have described may concern
some species for which other descriptions have been given,
perhaps a Hexagenia or a Heptagenia.

Of the various accounts concerning emergence given in the
literature, a description by Miss Morgan for Iron fragilis
(Heptageninas) appears to resemble the instance reported to me
most closely, so far as the ability to fly immediately upon
emerging from the water is concerned. I do not mean to imply
any identity of species. Miss Morgan says, "The nymphs
popped from the surface of the water and flew unsteadily
upward. * * * " She was probably not in a situation
which enabled her to describe what occurred before this, but
presumably some preliminary processes took place beneath
the surface. Another account which bears some resemblance
to the one I have given is by W. E. Howard and concerns
Polymitarcys albus. "I have seen the subimagos emerge and
arise from the surface of the water in great numbers, but always
just far enough from shore so that the nymph skins were
immediately swept into the current. * * * " Somewhat

April, 1922 EMERGENCE OF A MAYFLY 157

similar to this is Needham's description of the emergence of
Caenis dimimita . "It emerges from the water at nightfall
leaving its nymphal skin floating on the surface, and, alighting
on the first support that offers, sheds its skin again. * * * "
In neither of the last two accounts is it definitely stated
whether the mayfly issued from its nymphal skin after reaching
the surface of the water or whether the process began before
that. In the case of Iron Jragilis with regard to which Miss
Morgan uses the phrase, "popped from the surface of the water,"
it would appear that the shedding of the nymphal skin must
have occurred beneath the surface. The emergence I have
described, is, I believe, the only case on record in which such a
process has actually been observed.

LITERATURE CITED

Clemexs, W. a. —

1915. Life Histories of Georgian Bay Ephemeridas of the Genus Heptagenia.

Howard, W. E. —

1905. Polymitarcys Albus Say. In Mayflies and Midges of New York,
New York State Museum Bulletin 86 (Entomology 23), p. 60.

Morgan, Anna H.

1911. Mayflies of Fall Creek. Annals Entomological Society of America,
Vol. 4, pp. 104, 116.

Needham, James G. —

1905. Mayflies and Midges of New York State. New York State Museum

Bulletin 86 (Entomology 23), p. 35.
1908. Report of the Entomologic Field Station conducted at Old Forge,

N. Y., in the Summer of 1905. New York State Museum Bulletin

124 (Edu. Dept. Bull. 433), p. 178.
1918. Burrowing Mayflies of our Larger Lakes and Streams. Bulletin of

the U. S. Bureau of Fisheries, Vol. 36, 1917-18, p. 280 (also Document

No. 883, Bureau of Fisheries, 1920).

A NEW TYPE OF BRYOZOAN GIZZARD, WITH
REMARKS ON THE GENUS BUSKIA.

RAYMOND C. OSBURN and RUTH M. VETH
Department of Zoology and Entomology, Ohio State University

A certain few of the Ctenostome Bryozoa have long been
known to possess a gizzard or grinding organ at the cardiac
end of the stomach, though such information may be sought
for in vain in nearly all text books dealing with the group.

This structure is best known in the genus Bowerbankia
Farre, owing to the work of Hincks (1880, text figure on p. xxiii
and discussion on pp. xxiv-xxvii), and especially to the excellent
histological description by Calvet (1900, p. 227-230, 232-
234, PI. VI, Fig. 13 and PI. VII, Fig. 4).

Davenport (1891, p. 63) incorrectly homologizes the gizzard
with the lower end of the chilostome oesophagus. Calvet (1900,
p. 233) is undoubtedly correct in stating that it is the cardiac
end of the stomach which is thus modified.

The genera Amathia Lamouroux, Vesicularia Thompson and
Avenella Daly ell also possess a gizzard similar to that of Bower-
bankia. All of these genera belong to the family Vesiculariidae.

In the foregoing genera the gizzard has the appearance of a
rounded distension of the cardiac end of the stomach, or, to
quote Calvet (p. 228), "la forme d'une sphere tronquee aux
deux poles." The epithelial lining of the gizzard consists of
enlarged and elongated cells which are easily visible under the
ordinary low power of the microscope. The walls of these cells
at their inner free ends are heavily chitinized, so that each cell
thus presents a separate pointed chitinous tooth for the tritura-
tion of the food, (see Fig. 8). The bryozoan gizzard as thus
described is unique in its armature.

A strong layer of circular muscles completes the grinding
apparatus, which operates by rhythmic contraction and relax-
ation. Hincks (1880, p. xxvii) states that he has seen the food,
after passing through the gizzard, driven back into it by a
retrostaltic movement of the stomach and again submitted to
its action.

158

April, 1922 a new type of bryozoan gizzard 159

The new type of gizzard to be described has been discovered
in another family of the Ctenostomata, the Buskiidse, of which
the genus Biiskia Alder is the only representative. Alder (1856,
p. 156) failed to note the presence of a gizzard in B. nitens
and Hincks (1880, p. 532) also failed to discover it. Later
Hincks (1887, p. 127) described B. setigera from the Mergui
Archipelago, again failing to note the presence of a gizzard.
The s-mall size of the individual in Buskia (in B. armata the
length is .6 mm. and the breadth .2 mm.) and the much smaller
size of the gizzard in comparison with that in the Vesiculariidae,
together with the fact that it is divided into lobes, are respon-
sible, no doubt, for this failure to find it.

In 1912 Osburn (p. 256) re-described Verrill's Vesicularia
armata under the name Hippuraria armata (Verrill). In his
original description Verrill (Verrill and Smith, 1874, p. 710)
had not noticed the gizzard in this species. Osburn figured and
described the gizzard for the first time (p. 256, PI. XXIX, Figs.
84a and 84b). See Figures 1 and 2.

More recently Harmer (1915, pp. 85-89) has restudied the
genus Buskia and has found a gizzard in B. nitens and B.
setigera. If his figures (PI. 5, Figs. 10, 15 and 16), which are
small and not detailed, are to be relied on, the gizzard in these
species is of the same type as in the armata of Verrill. Harmer
indicates that armata belongs to the genus Buskia and is closely
related to B. setigera, a conclusion with which we are quite
ready to agree. There is reason for considering it a distinct
species, how^ever, for armata, as far as observed, does not
possess basal spines for the firmer attachment of the zocecium
and the zocecial wall is not perfectly transparent as described
by Hincks, but is of a yellowish horn color. Buskia armata
should be kept separate for the present at least, especially since
its distribution in the North Atlantic lies to the northward and
it tends to disappear toward the tropics.

Osburn's description of the gizzard (1912, p. 256) is as
follows: "a small but distinct gizzard, not completely sur-
rounding the gut, but forming several rounded lobes, with
pointed teeth projecting into the cavity." The four lobes of
the gizzard, with a band of circular muscles, is shown by
Osburn in Plate XXIX, Figs. 84a and 84b.

The nature of the gizzard lobes and their mode of formation
have been worked out by the junior author. The grinding

160 RAYMOND C. OSBURN AND RUTH M. VETH Vol. XXII, No. 6

structure consists of four mamillate, or low, rounded-conical
structures, which are heavily chitinized, provided with pointed
chitinous teeth of varying length and thickness and which are
continuous with the chitinous cone. The arrangement of these
cones, with their bases directed outward, gives a somewhat
squared outline to the gizzard in cross-section, as shown in
PI. I, Fig. 3. The rounded surfaces, with the teeth pro-
jecting into the lumen of the digestive tract, practically close
the cavity when the gizzard muscles are contracted, and the
teeth are interdigitated when in this position. In operation in
the living specimen, the gizzard lobes are seen to separate for
some distance and then to close strongly and sharply together.

While in Bowerba?ikia and related genera each epithelial cell
of the gizzard is chitinized on its grinding surface (see Fig. 8),
thus making as many teeth as there are cells, in Buskia this is
not the case. The hollow concavity of the chitinous cone is
filled with elongated epithelial cells, those nearest the center
being the longest. Together these cells secrete the chitinous
lobe as one continuous structure, the teeth also being a part
of the mass (Figures 3 to 7).

With its band of muscles, the entire gizzard in Buskia
armata measures only about .075 mm. in diameter. Each cone
measures about .0414 across the base and about .0234 in height.
The teeth are quite variable in size but average about .007 mm.
in height. Each cone bears about 30 teeth, though often the
number is much less than this, and the teeth at the tip of the
cone are larger and stronger than those farther down on the
side. The layer of chitin is about .002 mm. in thickness, when
fully developed, but thins out somewhat toward the base and
then suddenly becomes thickened at the margin to form a ring
about the base. The teeth are conical and hollow at the base
and the chitin forming them is somewhat thicker than that of
the cone on which they are borne. These relations are well
shown in Figures 3 to 7.

Much variation is shown in both sections and total mounts
in the exact form of the chitinous cones, possibly depending
somewhat upon the amount of chitinization. Sometimes the
lobes are almost hemispherical and seem to lack the rim around
the base. As such structures appear thinner and lighter in
color, it is probable that they have not reached their full devel-

April, 1922 a new type of bryozoan gizzard 161

opment. The teeth also vary much in form, size, number and
the angle at which they project.

The difference in the structure of the gizzard affords addi-
tional evidence for the separation of the family Buskiidse from
Vesiculariidse, the other family in which a gizzard is known to
occur. That Buskia represents a higher specialization in the
formation of a grinding organ can scarcely be doubted. There
are other evidences of a more highly specialized condition in the
greatly elongated and spiral arrangement of the bristles sup-
porting the collar and in the mode of branching, (see Fig. 1).
The presence of a lateral membranous area also marks this
family off sharply from the Vesiculariidse.

Buskia armata (Verrill) is the only species thus far recorded
from the Atlantic coast of North America. Its known distribu-
tion is from Massachusetts Bay to Beaufort, North Carolina.
On the southern New England coast it growls profusely, spread-
ing over hydroids, algas, etc. In this region it often rises in free
branches more than an inch in height, but toward the limits of
its range only the creeping adherent stage is seen.

LITERATURE CITED

Alder, J.

1856. Catalog of the Zoophytes of Northumberland and Durham. Transac-
tions of the Tyneside Field Club.
Gal VET, Louis.

1900. Bryozoaires Ectoproctes Marins. Montpelier.
Davenport, Charles.

1891. Observations on Budding in Paludicella and Some Other Bryozoa. Bul-
letin Mus. Comp. Zool. at Harvard College, t. XXII, 1891.
Harmer Sidney F.

1915. The Polyzoa of the Siboga Expedition, Part I, Entoprocta, Ctenosto-
mata and Cyclostomata, Leiden.

HiNCKS, T.

1880. British Marine Polyzoa.

1887. Polyzoa and Hydroids of the Mergui Archipelago. Jour. Linn. Soc.
Zool. XXI.

OSBURN, R. C.

1912. The Bryozoa of the Woods Hole Region. Bulletin of the Bureau of
Fisheries, Vol. 30, 1910. Document No. 760, Washington.
Verrill, A. E. and Smith, S. I.

1874. The Invertebrate Animals of Vineyard Sound and Adjacent Waters.
Report of the Commissioner of Fish and Fisheries for 1871-2. Wash-
ington, 1874.

162 RAYMOND C. OSBURN AND RUTH M. VETH Vol. XXII, No. 6

EXPLAXATIOX OF PLATE.

Figures 1 and 2 are from Osburn's Bryozoa of the Woods Hole Region. Figure 8
is modified fiom Calvet, Bryozoaires Ectoproctes Marins. Other
figures by the junior author.

Fig. 1. An individual of B. armata (Verrill), the zooid retracted. The gizzard is
shown in partial side view (at G) and the spiral bristles of the collar
(at B).

Fig. 2. Coriiplete intestinal tract, showing the oesophagus (O), gizzard (G),
stomach (S) and intestine (I).

Fig. 3. Diagrammatic cross-section of gizzard showing circular muscles (M),
epithelium (E) and chitinous cone (C) with teeth.

Fig. 4. Diagrammatic side view of a cone showing the arrangement of the teeth
and the thickened rim around the base.

Figs. 5, 6 and 7. Camera lucida drawings of actual cross-sections of different
cones. Some of the differences in form may be due to the fact that they
are not cut quite in the same direction.

Fig. 8. Cross-section of the gizzard of Bowerbankia for comparison. Note that
here each epithelial cell bears its own chitinous tooth. The enlargement
is much less in this figure than in the others.

A New Type of Bryozoan Gizzard,
R. C. Osburn and Ruth M. Veth.

Plate I.

163

HABITS OF THE COMMON MOLE.*
Scalopus aquaticus machrinits, (Rafinesque).

F. A. HANAWALT
Department of Biology, Otterbein University

In the United States there are five genera of moles, Scalopus,
Parascalops, and Condylura appear in the eastern portion;
Scapanus and Neurotrichus are found west of the Rockies.
Of these genera, Scalopus is most widely distributed and
consequently best known and most divided into species and
sub-species. Jackson, in "A Review of the American Moles,"
has thirteen varieties of Scalopus listed and described along
with their geographical distribution. His work on moles is
notable and his analytical key gives an easy means of identifying
varieties, doing away with much of the confusion arising from
the same variety of mole appearing in various localities under
as many as twenty different names, the genera being confused
as well as the species.

The mole upon which this paper is based is Scalopus
aquaticus machrinus (Rafinesque). The observations regarding
it will deal primarily with those points to which other writers
have given little or no attention, or points upon which I have
found conflicting statements.

Moles are often said to be entirely insectivorous. This
statement, no doubt, is based upon dentition study, for the
study of the stomach contents will soon prove that moles are
rather omnivorous. It is commonly known that a large percent
of their food is made up of earthworms which they detect in
the soil through the use of the tactile hairs and the sensitive
nose. I have noticed that the motion of a wriggling worm
along the side of a mole will cause the latter to turn quickly
and press the worm down with the front feet and the head.
The mole then waits for further activity on the part of the
worm, apparently depending upon this to show just where it is.
If there is no further activity the mole turns its nose about in
an effort to locate the worm, presumably using the sense of

* Part of a thesis offered in partial fulfillment of the requirements for the
degree of Master of Arts from Ohio State University.

164

April, 1922 habits of the common mole 165

smell under these conditions. The nose is usually in motion,
but it is my belief that it is through a sense of touch rather
than through a sense of smell that the nose is most useful in
food getting when the food taken is alive and has the power
of motion.

I have found their method of eating earthworms interesting.
Small worms like Ilelodrilus Joetidus (Savigny) and Helodrilus
caliginosus (Savigny) are eaten entire, but larger worms like
Lumhriciis terrestris (Linnaeus) are torn to pieces with the
claws. A mole may work several minutes upon a large worm,
tearing it into strips and short sections, rolling it about with
the front feet and the mouth, thus getting the parts of the
worm almost free from the ingested earth before eating them.

Whenever I have offered captive moles any of the insects
or insect larvae commonly found in the soil, they ate them
greedily. Beetle larvae, ants, maimed flies, and small Crustacea
were all eaten. Large beetles such as Lachnosterna and
Lucanus were also eaten, but the wing covers and hard parts
of the exoskeleton were generally refused. Prof. E. L. Mosley
has found that captive moles refuse wooly insect larvae, adult
Colorado potato beetles and their larvae. Analysis of stomachs
of moles show a preponderance of earth worms, a large per-
centage of larvae of Lachnosterna in season, various Carabidae,
and insect larvae of different sorts. The most noticeable
insect larvae were those of the Elateridae, no doubt due to the
fact that their tough bodies resist mastication more than the
soft bodies of other insect larvae. In the stomachs were also
found insect pupae, earthworm egg cases, grains of oats, corn
and grass. One mole taken from a clover field in December
had 95% of the stomach contents made up of small ants, and
since the ants were all of one species, this indicates that moles
are given to plundering ant hills.

Grass found in the stomach was at first thought to have
been introduced accidentally until a captive mole was found to
eat grass, making as high as one-fourth of a meal upon fresh
lawn clippings. This led to further experiments with wild
and captive moles to find out what vegetable food they might
take. It was shown, to the author's satisfaction at least, that
moles are guilty in some cases of eating sprouted corn and in
rare instances of eating roots and tubers. Moles in captivity,
when short of water, ate Irish potatoes regularly, and would

166 F. A. HANAWALT Vol. XXII, No. 6

eat freely of apples, apple being taken by some moles very
shortly after they had been captured. None ever ate sweet
potatoes or parsnips. One ate only sparingly of carrots.
The study of marks upon partially eaten Irish potatoes has
led some to say that moles could not have made them, but
that they were made by mice. My observations of captive
moles show that marks resembling tooth marks of mice are
made by moles, both by the teeth and the claws of the front
feet.

Moles in captivity will eat soaked corn readily and will
live for several days upon this diet alone. When this diet has
been supplemented with apples and earthworms three or four
times a week I have succeeded in keeping moles alive for as
long as forty-one days. Soaked wheat and oats are not as
readily eaten as is soaked corn. It seems that when a mole
burrows unerringly along a corn row, he not only follows the
line of least resistance through the soil, provided by the mark
of the planter shoe, but he also eats some of the corn along with
other food found. Whether the corn is eaten or not, the
young plants usually die from having their root systems torn
to pieces.

Moles will usually take meat when captive, eating lean
beef, fish, fresh or salted pork, mice, frogs, and even small
snakes. They have no trouble in disposing of live mice such
as Microtus pennsylvanicus (Ord) this fact making the theory
that potato tubers are eaten by mice that follow along the
runways of moles very untenable. In eating furry animals
the mole discards most of the hair and skin, also some of the
larger bones. The hind feet and strips of skin are all that are
usually left after a meal upon a meadow mouse.

The mole does not ordinarily drink. I observed only one
captive mole drink, taking water by lapping. In dry summer
months moles may be found far from water and in such situation
must depend upon the water found in their food. It would be
of interest to observe moles in dry weather when earth worms
are scarce or excessively deep, to see if it is then that depreda-
tions in potato patches occur. Observations upon captive
specimens indicate that plant roots and tubers are eaten chiefly
to satisfy thirst.

Curiously enough, no reference is made by most authors to
the swimming habits of moles. Some state that the mole can

April, 1922 habits of the common mole 167

undoubtedly swim, and one author has given the mole great
powers of swimming, due to powerful strokes of the great front
feet. Scalopus aquaticiis machrinus (Rafinesque.) does swim
well, but the front feet play no part in propelling the animal,
they are used only in turning or in righting when not on an
even keel. The front feet are held together under the chin
where they cut the water like the prow of a tiny motor boat,
the propeller in this strange craft being the webbed hind feet
which alternate with each other in their movements. The
flexible nose is held curved upwards, raising the nostrils well
above the water. I have used a stop-watch upon swimming
moles and find that the swimming rate averages about a foot
per second. I have found the maximum speed in running to
be only a little more than double the swimming rate, averaging
26.7 inches per second in the specimens tested. Both of these
speeds are low, the small hind feet being poorly adapted for
swimming and the large front legs so wonderfully adapted to
a strong side thrust in digging are poorly adapted to running.

Moles usually bear a few external parasites, such as fleas
and mites, and numerous internal parasites. Nematode worms
are not uncommon in the stomach. The most common internal
parasite is Monilijormis moniliformis (Travassos). The intes-
tines are sometimes so clogged with these parasites that one
wonders how food is able to pass along the tract. Moles
containing as many as three dozen of these worms give no
evidence of the fact in any way unless it be in their ravenous
appetites. They must have no difficulty in supplying both
themselves and their parasites with food, for even the most
heavily infested moles that I observed were in good condition
and seemed to have as much fatty tissue as moles not infested.
Of twenty moles taken in August, 1917, the average for stomach
worms was 1.2 and for intestinal worms 16.4 per animal.
The intestinal worms of one animal numbered 23, their average
thickness 1.4 mm. and their total length 333.5 cm. The length
of the intestine of the mole was 115 cm., making the length
of the enclosed parasites nearly three times the length of the
intestine that held them.

The genus Moniliformis is placed in the subfamily Gigan-
torhynchincE (Travassos, 1915) this being a subfamily of the
GigantorhynchidcE (Hamann, 1892). The members of this
genus are parasites in the intestines of rodents. As far as I

168 F. A. HANAWALT Vol. XXII, No. 6

know the mole has never been included in the list of hosts of
this genus of Echinorynchs. If this be true it is not surprising,
for I find that moles of one collecting ground may be heavily
infested with the parasites, while moles a few miles away may
be entirely free from them.

On account of their tunneling in lawns, flower gardens,
truck patches, golf hnks and such places, the mole is commonly
regarded as a pest. From the standpoint of his food, he is to
be considered beneficial, but when a mole uproots hill after hill
of melons to get the larvae of the striped cucumber beetle
projecting from the roots of the vines, the cure is decidedly
worse than the disease. Once the mole finds a good feeding
ground he can not be easily driven away, and if he is doing any
real damage it will be found advisable to destroy the animal
in some way rather than to attempt to make him seek other
feeding grounds.

Experiments made by placing salt, sulphur, pepper and other
irritating substances in mole runs in an attempt to drive them
out of lawns and golf links have proven failures, the animal
simply building another set of tunnels in another part of the
lawn or golf course. One often hears that castor bean plants
about a garden will keep moles away, but the writer has seen
moles burrow directly under castor bean plants. Dogs can
be trained to catch moles, but they will not eat them,
presumably on account of their bad odor. Cats also catch
moles, usually at night, they also refusing to eat the captured
animal. Poisoning is one of the artificial means that may be
used in reducing the number of moles, the most convenient
method consisting of soaking corn, then placing strychnine or
arsenic in the heart of the grain by pricking it in with a tooth-
pick or other blunt instrument. The poisoned bait should be
placed in the mole runways, one grain of this being sufficient
to kill a mole. Care should be taken to select no poison with
a decided odor, as this will lessen the efficiency of the method.
I have found arsenic the most satisfactory poison to use.

The most common means of destruction, also the most
efficient, is the use of traps. Traps of the nature of pitfalls
have proven useless in the hands of the author, yet if they are
carefully set they occasionally make a catch. Moles are often
found drowned in wells walled up with boulders, but in this
case it is probably thirst that causes the mole to lose his life in

April, 1922 habits of the common mole 169

this manner. Of the various spring traps set in runways, one is
of equal value with another if properly set, but on account of
the use to which the skins may be put, the harpoon type of
trap is the least desirable.

Scalopiis aquaticus machriniis (Rafinesque.) will likely con-
tinue to be an animal small in numbers among us on account
of its breeding habits, for it breeds only in early spring of each
year and the number at birth is small, averaging four or five.
On account of its food habits and its depredations in lawns and
cultivated fields, it will always be of economic value, and of
special scientific interest on account of its subterranean habits
and high degree of specialization.

LITERATURE CITED

Jackson, Hartley H. T.

1915. "A Review of the American Moles." Bureau of Biological Survey.
N. A. Fauna No. 38.

SCHEFFER, ThEO. H.

1917. "Trapping Moles and Utilizing Their Skins." U. vS. Dept. of Agr.
Farmers Bui. 832.

MOSLEY, E. L.

Unpublished Work. "Natural History of the Mammals of the Central and
Eastern States."

A CASE OF UNHINDERED GROWTH OF THE INCISOR
TEETH OF THE WOODCHUCK.

STEPHEN R. WILLIAMS
Department of Zoology, Miami University

Late in the fall of 1921, long after the normal woodchucks
had gone into retirement for the winter the groundhog whose
head is show^n herewith was caught near Oxford in a trap set for
skunks. The trapper killed the woodchuck with a club, breaking
two of the teeth in the process, one of which he picked up. The
pelt being valueless he cut off the peculiar looking head and
threw the body away making the observation that the animal
was much undersized and excessively thin.

The head was brought in, mounted by a local taxidermist,
and put upon exhibition in an office window. I take this oppor-
tunity to thank the exhibitor, Mr. Chas. Wright, for permis-
sion to photograph the mount.

There is no evidence as to what happened to deform the
animals, but the results are clear. In some way the incisor teeth
of the woodchuck's lower jaw became deflected to the animal's
left side and the incisors of the upper jaw turned enough to the
right so that the two sets passed each other and no longer could
be kept worn down by gnawing.

The left lower incisor grew in a regular curve up to the eye,
ploughed through the eye and blinded it. It can be seen that
the direction of growth was changed into a section of a larger
circle as the end of the tooth slid backward along the frontal
bone. The continuous curving growth of the tooth was not to
be resisted by bone, however, and so the point of the tooth per-
forated the skull a short distance behind the eye socket and is
said by the preparator to have penetrated the brain also.

This perforation of the skull and brain must have been some
time before the animal's death, for the last visible part of the
tooth is sheathed with a connective tissue envelop probably
continuous with the periosteum of the skull through which the
tooth passed. How far into the brain the tooth penetrated can
never be determined. The whole socket of the eye was a sup-
purating mass when the animal was killed.

170

April, 1922 unhindered growth of the incisor 171

The right lower incisor was crowded between the left lower
incisor and the bones of the left side of the face. It shows the
effect of pressure and also that it was rubbed between its mate
and the skin of the face. The hair on the face is worn very close
along the line of this tooth also. Unfortunately since it was
broken across when the animal was killed, no more accurate
information can be had as to its position. The photograph
shows it ending freely over the part of the left lower tooth
which disappears into the head.

The stump of the right upper incisor is shown on the animal's
right. The tooth is curving sharply and if the part broken off
could be found it might show that the point was nearly as high
as those of the teeth on the lower jaw.

d. i. dx. — Right upper incisor (broken off).

d. i. s. — Left upper incisor which passes down the animal's throat.

e. s. — Left eye socket through which the lower incisor plowed.

V. i. dx. — Right lower incisor (broken off but placed about as it must have been

in life).
V. i. s. — Left lower incisor penetrating the skull and brain.

The left upper incisor turns directly down and back into the
mouth and, according to the man who mounted the head,
extended down the throat for more than an inch.

This case is a fine example of the way rodent chisel teeth
with persistent pulps (or with continuous growing germs) act
when for any reason the wearing of the teeth is hindered. iThe
fate that follows is inexorable and starvation is its logical end.

How^ did the animal get any nourishment at all? The bodies
of the upper and lower incisors firmly fixed side by side seem to

172 STEPHEN R. WILLIAMS Vol. XXII, No. 6

make entrance of food into the mouth from the front absolutely
impossible. There is, however, a small section of the mouth
opening to the left side just behind the origins of the lower
teeth which looks as though it could have been used. The hair
around this corner of the mouth looks rubbed and worn thin.
Possibly by turning the head to one side and by manipulating
with the tongue as effectively as it could act under the per-
manent tongue depressor (the left upper incisor) some leaves
and other small fractions of plant tissue could be forced far
enough into the mouth to be caught and ground up by the
back teeth.

Whatever explanation one makes concerning the method of
feeding, the animal certainly obtained enough food to keep
alive, for it was killed by the trapper. And from the date of
capture, nearly a month after the normal woodchucks had dis-
appeared, we can be just as sure that the creature had been
unable to hibernate because incapable of accumulating fat.

There is no means of learning the age of the animal, but
since these rodent teeth grow rapidly it was probably a young
one and these tusk-like teeth the unworn accumulation of one
season's growth. It seems impossible to imagine a half blind,
deformed and infected animal ever having been able to store
fat enough to live over even one hibernation period.

The Ohio Journal of Science

Vol. XXII May, 1922 No. 7

SOME COMMON MISCONCEPTIONS OF EVOLUTION*

RAYMOND C. OSBURN

Department of Zoology and Entomology, Ohio State University

The living world embraces such a variety of form and such
a range of structure and mode of life that, to the average man
without scientific training, it must always have seemed a great
unravelable tangle, inexplicable on any other ground than
that of special creation — that some omniscient and omnipotent
being made the various forms of life and established them
in the world, for his own delectation, if for no other purpose.

But the greater scientific and philosophic minds of the
past centuries have been able to discern an order in the midst
of this apparent chaos and, from the time of the ancient Greeks,
repeated attempts have been made to point out this order and
to suggest some more acceptable reason for its existence than
to assume that somebody made it all at once and set it up
ready to run to the end of time. Naturally, the earlier attempts
to convince mankind that there has been a gradual evolution
of the present complex order of existence were unsuccessful
for want of sufficient knowledge.

It is probable that Aristotle, Lucretius, St. Augustine,
Harvey, Buffon, Lamarck, Erasmus Darwin and other great
minds of the past apprehended clearly enough the scheme
of gradual development of life on the earth, but they lacked
sufficient knowledge of the facts to make a convincing argument
on a matter apparently so revolutionary. Furthermore, from
Augustine on down, they were confronted by a dogmatic
theology which effectually blocked the progress of scientific
thought for many centuries.

* Retiring President's Address before the Ohio Academy of Science, April 14^
1922.

173

174 ILWMOND C. OSBURN Vol. XXII, No. 7

The scientific men of tiie past century and a half, especially,
have established the following important facts with regard to
life on the earth:

1. There has been a gradual development from simpler
to more complex forms.

2. There have originated multitudes of new species as
well as whole new phyla since the geological record began.

3. Other multitudes of species as well as whole orders
have passed out of existence in geological time.

4. These changes have been the result of orderly procedure
and not of cataclysmic action.

5. There has been continuity of life and uniformity of
biological processes.

6. Untold ages of time have been involved since life first
appeared on the earth.

The only satisfactory explanation of these facts is found in
organic evolution. All those who have the best right to an
opinion on this matter — the scientists who have investigated
and carefully weighed all the data, are agreed that there is
no other satisfactory method of putting the facts together in
logical order. All of the facts and deductions are open to
re-examination, but as they have been carefully scrutinized
already by large numbers of investigators and from all angles,
it is not likely that any different interpretation will be found
possible.

Notwithstanding this concensus of opinion among those
qualified to judge, there has always been a number of
"conscientious objectors" among those untrained in science,
on the gi-ound that evolution opposed certain established
theological dogmas. A theistic conception of evolution, how-
ever, satisfied the more liberal minded of these objectors and
there has been a gradual diminution of opposition since the
time of Darwin. Recently, however, a well-known, quixotic
platform speaker has made a virulent attack on the law of
evolution and the weight of his oratory has carried so many
people with him, that opposition to evolution has spread like
an epidemic through certain portions of this country. If
he had chosen, instead, to attack the Copernican theory that
the planets revolve around the sun, he would no doubt have
convinced many unthinking people -and those unfamiliar with
the facts. This campaign against a law of nature would be

May, 1922 common misconceptions of evolution 175

amusing were it not for the fact that it shows such a deplorable
state of ignorance among our supposedly enlightened people,
with regard to the progress of science.

It is true that many otherwise highly educated persons do
not have a very clear idea of the law of evolution and that
many misconceptions are current among them. In the effort
to clear up some of these mistaken notions let us consider
a few of those which appear to be most commonly held.

It is commonly, but mistakenly, supposed that scientific
men are divided in opinion as to the truth of evolution. This
idea has arisen from the discussion of certain minor matters,
or side issues, such as the mode of origin of species. It may be
safely stated that the only questions concerning evolution that
are debated by the biological scientists, are those that have
to do with the method of evolution — the discussion of the means
employed by nature in causing the changes that are admitted
to have taken place, and the paths along which the advance-
ment occurred. Though there is still much discussion as to
just how it has come about, no scientist at the present time
has any doubt of the fact of evolution. Furthermore, all will
admit that three great interacting factors are to be found in
variation, however it may be caused; in selection, by which
inadaptive changes are eliminated and adaptive changes
permitted to continue; and in heredity, by which any advance,
involving the constitution of the organism, may be perpetuated
through succeeding generations.

Variations of some sort are necessary, of course, however
they may be caused, or there could never be any change and,
without change, naturally, no evolution. Moreover, the varia-
tions must be of a particular class, for they must be inheritable,
and, as far as we know, only those variations are capable of
being inherited which involve a change in the germ plasm.
The "discontinuous variations" of Bateson and the "muta-
tions of DeVries are the most marked of these germinal varia-
tions, but just how small a variation may be and still be
inheritable no one has yet discovered. Variation, then,
supplies the crude material for evolution.

Natural selection, that much misunderstood and much
abused term! — selection is merely another way of stating the fact
that variations of all sorts occur and that some of these may
benefit an organism, while some others may be harmful to it.

176 RAYMOND C. OSBURN Vol. XXII, No. 7

The beneficial variations are of value to the organism in solving
its problem of existence and, very naturally, such variations
tend to insure that the organism shall live to maturity and
through its reproductive period. If a variation is inimical to
its possessor, then selection naturally eliminates the organism
that possesses such a variation and that is the end of that
variation, since, if its possessor does not live, the variation
cannot be perpetuated.

Heredity is merely passing on to the next generation any
characters which may be a part of the germ plasm of the
organism. A species can find no way of continuing a variation
that is sufficiently harmful to cause the death of its possessor, or
even to pass on for very long a variation that is only mildly
disadvantageous. To indicate how important even a slight
advantage may be, allow me to quote from Prof. R. C. Punnett;
"If a population contains .001% of a new variety, and if that
variety has even a 5% selection advantage over the original
form, the latter will almost completely disappear in less than
a hundred generations." So, heredity becomes an important
factor for progress when coupled with variation and selection,
in that it gathers up the useful variations and concentrates
them in posterity. Or, as Prof. J. A. Thomson puts it, "The
true inwardness of heredity is a holding fast of that which is
good."

A misconception of heredity lies in the notion that it can
accomplish anything more than merely to pass on to future
generations what has already become a part of the germ plasm.
Just as selection has no evolutionary importance aside from its
reaction on variations of different degrees of value in adapta-
tion, so heredity has no place in evolution except as it passes
along such characters as have been already selected out as of
importance in the life of the organism. Any new variation of
the germ plasm, of value, is in this sense selected and, by
heredity, becomes a part of the more advanced organism, while
any new detrimental variation is swamped by the struggle for
existence and is not permitted to be passed along by heredity,
because its possessor is eliminated as unfit to meet the condi-
tions of life. It is possible, of course, for a character to be
merely useless without being harmful, but such features of an
organism must play a very small part in evolution.

May, 1922 common misconceptions of evolution 177

Darwin's theory of Natural Selection has been blamed by
undiscerning critics as being responsible for the Great War.
Unfortunately the term "natural selection," which means
nothing more than that one variation may have an advantage
over another one under the conditions of nature, has been
draw^n into bad company by those who have misused it, as, for
example, in association with the Neitzschian philosophy of the
superman. As a sample, we may quote the following statement
from von Bernhardi, "Wherever we look in Nature, we find
that war is a fundamental law of evolution. This great verity,
which has been recognized in past ages, has been convincingly
demonstrated in modern times by Charles Darwin."

Now, Darwin made no such interpretation, and various
later biologists have taken exception to this application of his
theory to human affairs and especially to war. Thus Thomson
wrote, five years before the war, in 1909, in "Darwinism and
Human Life": "I find no grounds for interpreting Darwin's
'metaphorical phrase,' the struggle for existence, in any sense
that would make it a justification for w^ar betw^een nations."
Dr. Chalmers Mitchell also comes to the conclusion (Evolution
and the War, 1915) that "They" (modern nations) "differ from
the units of zoology and botany in that the individuals compos-
ing them are not united by blood-relationship. Even if the
struggle for existence were the sole law that had shaped and
trimmed the tree of life, it does not necessarily apply to the
political communities of men, for these cohere not because of
common descent, but because of bonds that are common to the
human race."

A former president of this Academy, Prof. Maynard M.
Metcalf, stated in his presidential address before the American
Society of Zoologists on "Darwinism and Nations," "Human
communities, especially, have freed their members from much
of the stress of the struggle for existence, by substituting
co-operation for rivalry. . . Co-operation may perhaps fairly
be said to transcend natural selection as an influence upon the
life of highly civilized man. The higher the development of
human society, the more dominant becomes the principle of
co-operation. Only in the most primitive communities can
there be an approach to unrestricted natural selection. Indeed,
we know today no such human societies, and it is probable that
this stage of social evolution was already passed before man's

178 RAYMOND C. OSBURN Vol. XXII, No. 7

ancestors became truly men" (Anatomical Record, Jan., 1918).
Thomson again says, "The appeal to human history, which the
militarists make confidently, has seemed to many to show that
civilization was born out of war. But scientific inquiry does
not confirm this conclusion." Havelock Ellis writes (1919)
"War probably began late in the history of mankind," and,
"War was a result, and not a cause, of social organization."
As Thomson points out, "The militarists' appeal to history is
not any more convincing than their appeal to biology. The
facts are against them in both fields." Finally we should point
out, as has been done by various biological writers, that war
really is a detriment to both sides, especially between advanced
nations, by destroying the best of the younger men, whom the
nations at war can by no means afford to lose. Thus war,
instead of being contributory to the selecting of the best and
the survival of the fittest, too often results in the survival of
the unfit on both sides, to the great detriment of the human
race.

Thus no one has any cause to shudder at the mere term
"natural selection," since, to its gross misapplication as an
excuse for war, such as that made use of by ardent militarists,
the biologists have as much fault to find as any one. None but
the pre-war German philosophers would ever have agreed with
von Moltke that "war is a part of God's world order," and the
biologist, as much as any one, has a right to feel scandalized by
the crass misinterpretation of the selection theory which has
been placed upon it.

In a state of nature it is undoubtedly true that "the weaker
go to the wall," if by the weaker we mean those that are the
least adapted to meet the complex problem of existence, but that
does not imply, even in lower animals, that there is usually
anything like war between individuals of the same kind. The
struggle is confined to the effort of each to maintain itself as
an individual, and where competition is keen some have a
natural advantage of organization over others and these can
better solve the problem of existence while the others fall by
the wayside. Of course, the term selection is unfortunate in
that in the minds of many persons it is involved with the idea
of conscious choice, but no biologist has any difficulty in
holding to a proper interpretation of the term.

May, 1922 common misgonceptions of evolution 179

The notion seems to be prevalent that the proof of evolu-
tion hangs on the proof of the method of the origin of species.
Now, it happens that the exact cause of the origin of species is
still in doubt. This, however, is a comparatively small matter
and the law of evolution does not depend upon its solution at
all. We have abundant proof that multitudes of species have
originated and some of these have been traced through the
process of change, even if we do not know what caused the
change. Would anyone deny the fact that chickens hatch out
of hen's eggs, because the biologist does not pretend to know
all the processes involved in the development of the embryo?

It would be extremely interesting to know the causes of the
origin of species, but it is not necessary to the fact of evolution.
The origin of species in the past is an incontrovertable fact,
even if we do not know how they originate. Similarly, organic
evolution is an incontrovertable fact, though we may not know
all the processes concerned.

In recent years it has often been stated that "Darwinism is
discredited" and the average person takes this statement to
mean that evolution is discredited, for most people cannot seem
to get through their heads the fact that Dariuinism and evolution
are not synonymous. To what extent Darwinism is discredited,
however, depends entirely upon what we mean by the term
"Darwinism." Darwin's great contribution was establishing
the fact of evolution, than which no greater contribution has
ever been made to the fields of science and philosophy.

There is no thought in the minds of scientists of any possi-
bility of controverting evolution, any more than they would
deny the Newtonian law of gravitation or the Copernican
cosmology. If, however, we merely mean by Darwinism, the
same reliance on natural selection of fortuitous variations as the
method of origination of new species, which Darwin placed upon
it, then we may admit that there are many honest doubters as
to the method of evolution as stated by Darwin.

However, it is clear that the non-scientific public does not
distinguish between the fact of organic evolution and Darwin's
explanation of its cause. So, indiscriminating propagandists,
opposed to evolution, fix upon the discussion of Darwin's
proposed method and overlook entirely the fact which all scientists
are agreed upon.

180 R.\YMOND C. OSBURN Vol. XXII, No. 7

There are some controversialists again, who misuse, in
opposing evolution, the discoveries of Bateson, DeVries, and
others, in regard to mutations or larger steps, which throw
some doubt on the validity of Darwin's belief in the great
importance of minute variations. To accept the mutations of
DeVries only means to hasten the process of evolution, since the
steps in advance are so much greater than those suggested by
Darwin. For, after all, mutations are only germinal, and there-
fore, hereditary, variations of a more noticeable character,
and the acceptance of DeVries' views does not invalidate in
the least the importance of the principles of variation, selection
and heredity, but only makes possible the progress of evolution
at a much more rapid rate than does the Darwinian method.
Yet forsooth, because definite mutations are substituted for the
minor and fortuitous variations of Darwin, the undiscrim-
inating, ignorant and bigoted proclaim that evolution is over-
thrown. It would be as truthful to maintain that the Coper-
nican theory of the movement of the planets around the sun is
overthrown because a new asteroid is located now and then!
Besides it has no bearing on the fact that evolution has taken
place.

As to the controversy between those who hold with Darwin
and those who agree with DeVries I can see no special difficulty.
It may be that they are merely looking at different ends of the
same series. Bateson and DeVries at first assumed that muta-
tions must, of necessity, be breaks in the series, of considerable
importance. Later investigations, however, have shown that
mutations, or hereditary variations, may be much smaller
than they were at first supposed to be necessary and, in fact,
some of them are much less noticeable than some somatic
variations acquired during the life of the individual and not
heritable. The difference, which Darwin could not have known,
is a qualitative one rather than quantitative, on the basis that
to have any evolutionary value, a variation must affect the germ
plasm and not merely the body of the individual. On the other
hand too great a departure from the normal may have no evo-
lutionary importance because it renders the individual unsuited
for life or reproduction and so it is eliminated by natural
selection.

It is a common misconception that evolution is a force or
power by which things are brought to pass. Even the less dis-

May, 1922 common misconxeptions of evolution 181

criminating biologists may not be entirely free from this notion,
for I recall a little verse which used to be sung at Woods Hole,
that Mecca of the biologist, which runs as follows:

"Once I w^as a Rhizopod, a protoplasmic cell,
I had a little nucleus and oh! I loved it well,
Now I am a man at last, by evolution's power,
But oh, my little nucleus! I need thee every hour."

Evolution is merely an explanation of the way things have
come to be as they are, together with a statement of the natural
laws under which this has taken place. It involves uniformity
and continuity in nature and it applies to everything which has
undergone change in the course of time.

Some of the confusion in the minds of those untrained in the
methods of science is undoubtedly due to the lack of a clear
understanding of what is meant by "natural law." A natural
law is merely a formula indicating a method of procedure in
nature. It is a statement based on the classification of facts and
the comparison of their relationships. Civil law, as a man-made
rule of conduct implies a restriction and compels conformity,
and changes continuously with the varying conditions of human
society. Natural laws are merely conclusions drawn from the
scientific study of organized series of facts and are immutable
except as they are modified by a re-classification and re-state-
ment. A careful reading of the third chapter of Karl Pearson's
"Grammar of Science" is recommended to all interested in
this matter. "The civil law involves a command and a duty;
the scientific law is a description, not a prescription. The civil
law is valid only for a special community at a special time ; the
scientific law is valid for all normal human beings, and is un-
changeable so long as their perceptive faculties remain at the
same stage of development."

Another misconception of evolution is involved in the idea
that it always means an advance of some sort toward higher
organization. This idea is contrary to the very method of
evolutionary processes. Variations may occur in any direction
in any group of organisms, as far as we know, and, theoretically,
at least, they are just as likely to be retrogressive as progressive.
Secondary simplification is very commonly observed, especially
in parasitic organisms.

182 RAYMOND C. OSBURN Vol. XXII, No. 7

But what we are especially concerned with in this discussion
is progressive evolution in the sense that advances are made in
the direction of complexity and the origin of what we are
disposed to call higher animals, though we may be guilty of an
anthropocentrism in so doing. From the standpoint of the
Protozoan we might be considered degenerate, from the fact
that our cells have lost their capacity for independent life, and
have to live together or not at all. However, it is just this
very loss of independence of the individual cell, involving the
.principle of division of labor and necessitating specialization
for the better performance of some process and the co-operation
of various parts, that has marked the advance of more complex
organisms, whether we may be allowed to call them higher
or not.

But variations may occur in all directions and it has often
happened that the road to adaptation has lain in the direction
of secondary simplification of structure, and selection, in such
cases, means the elimination of the more complex, in order
to adjust the animal more closely to its environment.

The crayfishes of our American caverns have lost their
eyes, but they are highly adapted to a life in total darkness;
the sessile ascidians lose nearly all semblance to vertebrate
animals, which they clearly possess in the larval stage, by their
adaptation to sessile life; the whales and seacows have lost the
hind limbs and have taken on a fish-like form in adaptation
to aquatic existence. Among parasitic forms we see this
carried to the extreme. The tape- worm lacks entirely the
intestinal tract, and the parasitic barnacle Rhizocephala is so
profoundly degenerated that were it not for our knowledge
of its development we would not be able to state even its
affinities to the Crustacea. These degenerative changes, bring-
ing about the loss of simplification of structures, are just as
much the product of evolution as are the modification of a
fore limb to a wing in the bird, the highly organized mammalian
brain, or the complex social life of bees and ants. As Thomson
remarks, "It is plain that evolution may be down as well as up,
and that the gates of parasitism and other facile slopes of
degenerate life are always open. The tapeworm in its inglorious
ease is as much an outcome of evolution as the lark at heaven's
gate. "

May, 1922 common misconceptions of evolution 183

On the other hand, a point on which the man who merely
reads about evolution may be at fault, is in thinking that
variations are always necessarily fortuitous and occur in a
helter-skelter fashion. No doubt many variations are of this
nature, but there appear to be others which are directive in
their nature from the beginning and which keep on increasing
in value with successive generations, the "rectigradations"
of H. F. Osborn. The observation of this sort of serial suc-
cessive variations has led to the suggestion of the principle
of orthogenesis in evolution, the idea of successive changes
along the same line, each going a little farther than its
predecessor, so that in a comparatively short time a much
greater distance has been compassed than would be possible
by mere chance variation in any or all directions. The
literature of paleontology is full of such examples, dealing with
horns, teeth, limbs, spines, shells and other structures capable
of fossilization. The only satisfactory explanation suggested
to account for this, seems to be that a small chemical change
in the germ plasm may make possible another change of like
character and this supply the basis for the next step, and so on.
Only on some such basis as this can we explain the evolution
of certain structures which make their first appearance in such
a small degree that they have no apparent value in selection
and yet they keep on varying and advancing along the same line
until the structure becomes either adaptive and of value
to the organism or inadaptive to a degree sufficient to destroy
the species. Such structures may sometimes rise from insig-
nificant, non-selective stages to a condition of much importance,
to the organism, but, having started to vary in one line the
advance may keep on beyond the adaptive condition and
finally become a menace to the species. Such conditions of
racial senescence are known in numerous examples from the
fossil records.

A mistake commonly made by those not engaged in biological
work is to think that a great majority of the variations pro-
duced must have some value to the organism, since harmful
variations are seldom noticed in nature. It is true that
beneficial or at least harmless variations are the ones usually
noticed, because harmful variations are not perpetuated very
long. The biologist with an eye open to these things very
often observes them, but they never last long and the more

184 R-WMOND C. OSBURN Vol. XXII, No. 7

harmful ones never reach the next generation because they
are fatal to the organisms in which they appear. In every
species an abundance o^ such inimical variations may be
observed to produce the death of the organism, even before
hatching or birth.

The objection has often been raised by the less thoughtful
critics of the evolution theory that the principles of selection
and adaptation cannot be of much importance after all, since
we see many cases where adaptations fail to work and where
selection fails to eliminate such variations. A little more
insight into the problem would indicate that, after all, any
adaptation only needs to work sufficiently to be of benefit
to the species as a whole, and not necessarily to all individuals.
An adaptation is merely an adjustment to a certain condition
of life, and if the condition is changed, naturally the adaptation
does not exist; that is to say, the particular reason for the
existence of a particular structure, process or instinct, does
not obtain and therefore the organism is not adapted any
longer. Undoubtedly the reason why it is so difficult to keep
many wild animals in confinement, or why they often will
not reproduce in captivity, is because we cannot supply the
conditions for which they are adapted. A single adaptation
is not a master key, it will unlock only one particular gate
barring the pathway to existence, and if that gate is replaced
by another, that key is useless, but it may not be dangerous
to carry it.

There are, to be sure, many examples of imperfect adapta-
tion to be found on every hand and the biologist has not failed
to take them into account. The case should perhaps be stated
something like this:. vSuccessful organisms, by which we
mean all organisms that continue to exist, are fitted to meet in
a satisfactory manner, the ordinary conditions of their natural
environment. But the environment is always more or less
variable and the adjustment can therefore seldom be perfect.
The organism which is able to pass the adjustment test with a
sufficiently high rating will get along.

Another misconception along this same line arises from the
difficulty which man encounters in attempting to look at the
results of evolution from an impartial standpoint. He cannot
ordinarily escape from the limits of an anthropocentric evalua-
tion of other organisms, and measures all other creatures by

May, 1922 common misconceptions of evolution 185

his own foot-rule. Yet aside from his high nervous organization
it would seem that man has little to be proud of. Certainly,
in many other systems, he is not to be compared in the per-
fection of his adaptations with multitudes of other animals.
Bertrand Russell has facetiously remarked, "Organic life, we
are told, has developed gradually from the protozoon to the
philosopher, and this development, we are assured is indubitably
an advance. Unfortunately it is the philosopher, not the
protozoon, who gives us this assurance, and we can have no
security that the impartial outsider would agree with the
philosopher's self-complacent assumption."

Some one has referred to the results of selection as "the
survival of the adapted," and adaptation means merely the
ability to meet the conditions of existence in one way or another.
All organisms that continue to exist, must therefore be adapted,
and the supposedly lower organization of the protozoan may
be just as effective as the more complex structure of the
mammal. If the only proof of fitness is continued existence,
then the Foraminifera, which have had a long and continuous
career from the Cambrian period, at least, are far better
organisms than were the Dinosaurs, which lasted only through
a few millions of years in the Mesozoic and found continued
existence impossible. Man, who has been on the earth only
a mere half million years or so, has scarcely been given a fair
trial to prove his fitness, and the probabilities are that the
Foraminifera will continue to flourish long after man has
definitely proved his inability to cope with changing conditions.
We should, therefore, in justice to our logic, define carefully
what we mean by "higher," for higher specialization does not
imply higher adaptability.

A mistaken notion of evolution which has caused great
concern to the uninitiated is that it is a theory about the origin
of man from a monkey. Just why this idea should be so repellent
to a large class of people is difficult to see, for after all monkeys
are very respectable in comparison with some humans and,
furthermore, they are very high in the scale of animal organiza-
tion. We will all agree that they are incomparably higher
than the "dust of the earth," which many persons seem to
prefer for their ancestral stock.

But, of course, in thus speaking of the origin of man, no
evolutionist has the modern anthropoid ape in mind any more

186 RAYMOND C. OSBURN Vol. XXII, No. 7

than he has the modern man. Both are the evolutionary
products of a common stock and have taken different directions,
different Hnes of development. Their relationship lies through
a common type of remote ancestor. To approach that relation-
ship, one must go back to more primitive Primates, just as to
find connecting links between the Primates and Carnivora
one must go still farther back to more primitive mammals.

The nature of the "missing link" has exercised the mind
of the non-biological world very greatly, because of an erroneous
idea of what constitutes a missing link. As far as I am aware
this is always popularly applied to the evolution of man and
the usual opinion is that there should be found some inter-
mediate form between man and the nearest anthropoid ape, or,
because the general public is not informed or discerning in
these matters, between man and a monkey. But no biologist
would ever expect to find such a connecting link, for none could
exist. Man and the apes are contemporaries and so it is
impossible that one should descend or ascend from the other.
As well might one expect to find the missing link between
contemporary horses and tapirs, though both are descended
from the same group of primitive ungulate mammals. What
we do expect to find and what, in fact, we do find as we go
back in time is that we unearth simpler and more primitive
types of man until we come to a brain only two-thirds of its
present size, a prognathous jaw, less erect posture, etc., and
if we carry this far enough we will come to the generalized
Primate stock. If we trace out the ancestry of the apes we
will run back in a converging series to the same place. The
only sort of a connection existing between man and the apes
is that of origin from a similar source.

There is also a mistaken notion that evolution fails to
account for the origin of the mind of man. But the modern
psychologist and the student of animal behavior are agreed
that there is no necessity for assuming any break in the con-
tinuity of the series of phenomena in the evolution of mind.
The origin of mind is indissolubly linked up with the nature of
protoplasm, in its automatic movements, tropisms and reactions.
If we begin back as far as the protozoa, we may quote the
statement of Jennings that even the Amoeba "behaves as if it
had a mind of its own." From the indefinite condition of
automatism, irritability and conductivity, exhibited by the

May, 1922 common misconceptions of evolution 187

lowest animals, we arrive by gradual steps through the better
and better organization of a nervous system to a definite brain
and the improvement of this organ through various stages in
the vertebrates up to man, without a break. Parallel with
this we see the development of reflex action, experimental
behavior, instinct and learning, to intelligent behavior, inference
and rational purpose.

The evolution theory has been before the world in a con-
crete form for more than sixty years and all scientific men,
or those capable of forming a worth-while opinion, have been
agreed on it almost without exception ever since the con-
vincing statement of the case by Charles Darwin. Scientific
men have generally shown themselves to be capable of forming
sane opinions in their own field, but the general public still
finds it a difficult matter to accept the word of the scientist,
especially when scientific fact seems opposed to some long-
standing belief, or common uncritically-judged experience.
After nearly 400 years following the announcement of the
Copernican theory, a fair share of people still believe the world
to be fiat, because all they can see of it looks that way. Many
more still believe in witch-craft or the influence of evil spirits,
and a still larger percentage hold firmly to the moon as a
causative agent in the growth of crops, the curing of meat,
etc., etc.

After having written the above paragraph the writer came
across the following in the "Century Magazine" for February
(1922) in an article on "The American Gypsy," by K.
Bercovici: "The study of folk-lore * * * has demonstrated
that a certain stratum of the population is never reached by the
civilization of any given period. There are as many people
today who believe in witch-craft and black magic as there
were 500 years ago; as many people who go to fortune tellers
to have them read the cards, the palms, or tell the future as
seen in the bottom of an emptied coffee cup. "

In the field of medicine, notwithstanding the advance of
science, the general public is as gullible as ever, in the matter
of cure-alls, elixirs and nostrums, advertised to heal all "the
ills that flesh is heir to. " A recent widely distributed adver-
tisement of Dr. Morse's Indian Root Pills states for the benefit
of the public that "Malaria is due to a poisonous miasma,
which arising from the low swampy lands, becomes assimilated

188 RAYMOND C. OSBURN Vol. XXII, No. 7

with the atmosphere, " etc., while every scientific man has known
for the past 25 years that it can be distributed only through
the bite of an Anopheles mosquito.

There is scarcely a newspaper that does not occasionally
carry an advertisement of an astrologer, a crystal gazer, a
clairvoyant, or other similar kind of fakir, while the number
of people who still consult the medical almanac for the signs
of the zodiac and the changes of the moon is very large, even
in the most enlightened countries. The traditional super-
stitions of the primitive civilization of our forefathers still
hold sway in the minds of multitudes in spite of the advance-
ment of the few.

This is easily understood in the uneducated and in that
portion of the public whose intelligence rating is much below
the average, for such people either have no capacity for much
understanding, or no knowledge on which to base anything but
an unscientific belief — and when you come to that kind of
belief it is as easy to believe one thing as another, especially
if you are not particular as to the basis for it. There is a line
in an old hymn which runs to the efiPect that "blind unbelief
is sure to err. " It would have been equally true had it stated
that blind belief is sure to err. It is the blindness in either
case that results in the error. "Belief, in the scientific sense of
the word," says Huxley, "is a serious matter, and needs strong
foundations."

When we come to the educated portion of the public we
have some right to expect more discrimination and less general
credulity. We have a right to expect that they will refrain
from attempts to discredit the work of capable scientists
on the basis that it controverts some already established
belief. An educated man should at least be able to draw the
line between what he knows and what he doesn't know and
not attempt to pass judgment on matters outside of his field
of training. The educated man without scientific training
has no more basis for forming a proper judgment of the Law
of Evolution than of the Einstein Theory of Relativity.

I have said that no scientist doubts the broad fact of evolution
in the organic and inorganic worlds, but it is equally true
that in the minds of many of the unscientific, there still remains
not only a doubt, but a positive conviction that evolution is
merely a vague guess of the scientist and that it is not necessary

May, 1922 common misconceptions of evolution 189

to place any reliance on his views. If the question as to the
truth of evolution were to be put to a public vote today, I
have little doubt that the scientists would be overwhelmingly
voted down.

The newspapers still mistake scientific discussions as to
the method of evolution for doubts as to the fact of evolution
and often herald this error in glaring headlines, such as "Great
Scientist Disputes Darwinian Theory," "Evolution Theory
Disproved, " etc., etc. This happened no later than last winter
following Prof. Bateson's address before the American Associa-
tion for the Advancement of Science at Toronto. At the close
of his address, Bateson said, "Let us then proclaim in precise
and unmistakable language that our faith in evolution is
unshaken. * * * q^j. (doubts are not as to the reality or
truth of evolution, but as to the origin of species, a technical,
almost domestic problem. Any day that mystery may be
solved." Though the greatest pains were taken to insure that
no mistakes should creep into the subject matter presented to
the newspapers for publication, the headliner got in his deadly
work uncensored, with the result that the next morning's
papers carried headlines announcing the unwarranted assertion
that this famous British scientist disputed the fact of evolution.

It is quite apparent that the mass of the reading public
are unable to distinguish the difference between fact and
method in this field of thought. The campaign against evolu-
tion just now being waged by a certain notorious speaker is a
case in point. When a man who is very evidently unskilled
in the handling of scientific data, unfamiliar with the details
of the subject, and solely by an appeal to the emotions through
his oratorical presentation, can obtain a wide hearing throughout
the country and can even influence a state legislature to con-
sider measures for preventing the teaching of evolution, we
must admit that the idea has not yet been fully accepted by
many so-called educated people.

The editor of "The Congregationalist, " (March 16, 1922,
p. 32G), however, wisely points out that "Addresses such as
that which Mr. Bryan delivered in Philadelphia will do ver}'
little to affect the course of science, but we think they are
calculated to do irreparable harm to religion." And again,
"When one realizes the patience, care and courage with which
the sincere scientist pursues his quest of truth, there is some-

190 RAYMOND C. OSBURN Vol. XXII, No. 7

thing anomalous in the effort to dominate that field by the
superficialities of platform oratory."

Professors Henry Fairfield Osborn and Edwin Grant Conklin
have also recently replied, through the "New York Times"
of March 5, to an article by Mr. Bryan in an earlier number of
the same paper. Osborn points out that "evolution takes its
place with the gravitation law of Newton." Conklin com-
ments on Bryan's attempt "to establish an inquisition for the
trial of science at the bar of theology," and grows facetious
over his proposition "to repeal a law of nature by a law of
Kentucky. "

Mr. Edward M. Kindle, of the Canadian Geological Survey,
writes in a recent number of "Science," "A Don Quixote of
Mr. Bryan's calibre only appears once or twice in a century
and the opportunity to study in cold print the celebrated
Nebraskan's proposal to resurrect the 'special creation of
species' myth must be appreciated by our scientific brethren
who are interested in studying the mysterious ways in which
the human mind works when it approaches subjects unfamiliar
to it."

It might be added that the English churchmen knew enough
to quit fifty years ago when the proof of evolution was
demonstrated to them. The modern opponents of the theory
have not a single idea at their disposal that was not worn
threadbare and proved useless a half century ago, while the
facts supporting the theory have accumulated continuously
and voluminously. The more enlightened churchmen the
world over, long ago accepted evolution as one of the great
fundamental truths, leaving only the ignorant and prejudiced
among them to butt their heads against the wall of scientific
■evidence.

Why then, with this mass of evidence which is so clear to
the mind trained in the formation of scientific conclusions,
has not the general public been more ready to accept these
conclusions? Has the public no faith in the findings of the
trained scientist? It would seem so, not only in this matter,
but in many others. Who is to blame for this condition of
affairs? I fear that the scientists themselves are considerably
at fault for not making more effort to place their discoveries
before the public in such form that they can be " understanded
of the people." Scientists have proved to be very poor

May, 1922 common misconceptions of evolution 191

propagandists. The facts and discoveries of science are so
interesting to them that they go from one research to another
without attempting to make clear to others what they have
accomplished. If investigators are constitutionally unable to
make their meaning clear to the reading public, then we need
a group of interpreters who will make it their purpose in life
to investigate the investigators and make known the truths of
science to the masses of people who may be able to understand,
if the facts are written in their language.

Just where does the evolution theory stand today in the
minds of scientific men engaged on problems connected with
this field of knowledge.

1. That there has been a cosmic evolution, no one familiar
with the facts can doubt, though we may still be unsatisfied as
to the truth of the nebular hypothesis of Laplace or the aggrega-
tion theory of Chamberlain as they concern the formation of
the earth.

2. That there has been evolution, in the form of progressive
changes of the earth itself, no one capable of forming a proper
judgment can doubt, though we may still question the number
of aeons it has taken to round the surface of the earth into its
present form, and the exact mode of formation of certain rocks
and strata may still puzzle us somewhat.

3. That there has been an evolution of organic life on the
earth no one familiar with the accumulated data will doubt for
a moment. The facts are so patent that one does not even
have to possess a very logical mind to be convinced of the
truth. The succession of animals and plants from lower to
higher forms in past time, as shown by paleontological studies,
is as clear and straightforward as any story which research
has ever brought to hght. This, coupled with the facts of
embryology and comparative anatomy, yields a truth which
no unprejudiced man can deny. For any one to do so merely
proclaims his narrow-mindedness and prejudice and classes
him among those of the last degree of blindness who "will
not see."

4. That modern man himself is just as patently a product
of evolution is clear to anyone familiar with the findings of
paleontological anthropology, even if we do not consider the
evidence from embryology and comparative anatomy. Our
knowledge of fossil man takes us back through several extinct

192 RAYMOND C. OSBURN Vol. XXII, No. 7

human species — Neanderthal, Heidelberg, Piltdown, Foxhall
and Trinil Man. These extend successively farther and farther
back, through the different glacial periods to the later Pliocene,
over time variously reckoned in years around 500,000. Through
this succession of human species we can trace the gradual
development of the cranial capacity to an increase of at least
50%; the retraction of the face from a prognathous to an
orthognathous condition, the development of a chin, making
possible the free use of the tongue in speech; the completion of
the erect posture, and various other features by which man has
become physically differentiated from his nearest animal kin.
Along with this physical progress we can trace, pari passu, the
evolution of his civilization.

Granted that we do not yet know all the processes by
which these changes in man have come about, the fact that they
have come to pass is so evident that only the ignorant, or he
who willfully ignores the truth for his own ends, will attempt
to dispute the fact. Place what interpretation on it you wish,
the fact remains. I hold no quarrel with the man who accepts
the fact and interprets it as the method of. a supreme being
for working out his eternal plan, or, as John Fiske said, "God's
way of doing things."

Only we must not let our religious beliefs get the better of
our common sense appreciation of facts in this or any other
matter. There is no thing as sacred as truth, in whatever
form it comes, and if it interferes even with a long-established
belief, then it is time that the basis for that belief is looked
into.

We have seen that the evidence of evolution does not rest
on guesses or interpretation, but on facts, and not in one field
only, but that astronomy, physics, chemistry, geology and all
the biological sciences tell the same story in the same way, that
of uniformity, continuity and progressive changes.

Gradually, of course, this natural law will receive general
acceptance among the reading and thinking public. In the
meantime, whenever some misinformed or bigoted egotist
displays his ignorance of scientific matters, there are two things
which we may do ; either we may attack his mis-statements and
set the unscientific public in the right through the press, or we
may follow the plan adopted by the man who was kicked by
a mule, and just "consider the source."

DYNAMICS OF THE LITHOSPHERE.*

O. C. JONES and GEORGE D. HUBBARD
Department of Geology, Oberlin College, Oberlin, Ohio

Introduction—

1.

Definitions.

2.

Thesis.

Astronomical and Physical Data —

1.

Precession.

2.

Nutation.

3.

Variation of Latitude.

4.

Shape of Earth.

5.

Plumb Line.

6.

Pendulum.

7.

Cavendish Method.

8.

Chemical Balance.

9.

Tides.

10.

Support of Load.

11.

Relative Density of Solid and Molten Rocks.

12.

Behavior of Rocks under Pressure.

Geologic and Seismographic Data —

1.

Geological Climates.

2.

"Original Crust."

3.

Geographic Distribution of Igneous Intrusion.

4.

Seismographic Records.

Data of

• ISOSTASY.

Data of

■ Diastrophism.

Centrosphere.

Crust—

-

1.

Depth.

2.

Density.

3.

Adjustability.

4.

Vulcanism.

5.

Mountain-making.

6.

Faulting.

7.

Causes of Lack of Adjustment.

8.

Earthquakes.

9.

Continental Creep.

10.

Some Immediate Causes of Adjustments.

11.

Deltas.

12.

Continental Masses and Ocean Basins.

Conclusions.

* Presented before the Geology Section of the Ohio Academy of Science
April 15, 1922.

193

194 O. C. JONES, GEORGE D. HUBBARD Vol. XXII, No. 7

INTRODUCTION,

It is a characteristic of the human mind that the things
least easily understood are the things most desirable to know;
and this insatiate curiosity frequently devises means to unlock
the hidden and to overcome the impossible. It has been in
large measure this psychological impetus that has prompted
studies dealing with the unattainable central structure of our
globe, and with the slow, invisible adjustments and responses,
to which terrestrial matter is subject.

By lithosphere is meant the solid or rock part of the earth,
not water and air, but probably all the rest from center to
circumference. In order to gain an accurate impression of
the adjustments taking place in the earth's outer part and of
its physical condition, it is necessary to consider the whole
problem of the interior of the earth. All evidence relating to
the physical condition of the interior of the earth or to the
adjustments of the earth's substance will, therefore, be first
drawn together without statement of its reference to the
problem; then conclusions will be drawn from the facts. In
this way the influence of theories which may or may not be
true will be avoided to some extent.

Our thesis is that essentially all the problems of the dynamics
of the lithosphere resolve themselves into the problem of
adjustment of strains and stresses in the structures and
materials of the earth, adjustment to the equilibrium form of
the earth, through the force of gravity, involving diastrophism,
vulcanism, and gradation.

THE ASTRONOMICAL AND PHYSICAL DATA.

Astronomy has furnished the geologist three lines of argu-
ment pertaining to the physical condition of the earth's sub-
stance: These are precession and nutation, variation of
latitude, the shape of the earth.

Precession. — Because the axis of the earth describes a
cone in its motions, tracing a circle about the pole of the
ecliptic, the equator, which preserves about the same inclination
to the ecliptic, moves so that its intersections with the ecliptic
pass in a retrograde direction opposite to the earth. Thi.<^
motion is termed the precession of the equinoxes.^ Precession

^Encyclopoedia Britannica.

May, 1922 dynamics of the lithosphere 195

is caused by the fact that the attractions of the sun and moon
are not a single force acting through the earth's center of
gravity. Since the variation is due to the attraction of forces
which are estimatable, methods of calculation are possible by
which the mass of the earth may be revealed.

Nutation- is a vibratory motion of the earth's axis, pro-
ducing a wavy circle of precession, due to the unequal attraction
of the moon on the equatorial ring of the earth. This, too,
affords another method or means of calculating the earth's
mass.

Variation of latitiide^^'" is caused by a shifting of the axis
of rotation within the sphere so that its polar extremities
wander in a circle of about fifteen (15) meters in diameter. By
computation it should have a period of 305 days; but Chandler,
from a great mass of data, discovered an actual period of 427
days.* Such a retardation can be due only to a shifting of
the equatorial bulge, by the lagging adjustment of which
retardation of the period is effected. Now since adjustment
in the rocks is slow and incomplete, a tide must be set up in
response to the strains developed by the shifting of the axis,
because water is very adaptable to external force. Dr. Bak-
heyzer and Mr. Christie have independently investigated
this problem of tides and both conclude that there is a tidal
variation with about a 430-day period.

The shape of the earth ^~^ has been a subject of long and
extensive study into which we do not need to enter. Suffice it
to say that the shape has been determined to be very nearly
an ellipsoid of revolution, showing that the earth's substance
is sufficiently plastic to be nearly perfectly adjustable to
rotational forces. The superficial exceptions will be discussed
later.

Schweyder^ has recently determined the nutation period as
432.8 days.

The physical data throwing light on the condition and
responsiveness of the earth's substance are varied and extensive.

-Encyclopoedia Britannica.
^Ibid.

•'Darwin: Tides, Chap. xv.

^Chamberlain, Reed, Hayford Schlesinger, Smithsonian Rpt., 1916.
''Encyclopoedia Britannica.

'Poynting & Thompson: Text Book on Physics.

^Schweyder W. Naturwissenschaften, 1917, Potsdam, Germany, pt. 38.
Quoted from Jour. Geo!. 1921, v. 29, p. 396.

196 O. C. JONES, GEORGE D. HUBBARD Vol. XXII, No. 7

The plumb li?ie^~^° has been used near mountains to estimate
the mass of the earth. The deflection from the vertical,
due to the attraction of the mountain, is measured. The mass
of the mountain is then calculated, and from these data the
mass of the earth is calculated. By this method Maskelyne,
in 1775, secured a mean density of 5. and James, in 1854,
obtained 5.32.

The pendulum^~^^ was first used by Bouguer. The number
of swings of the pendulum at the surface are compared with the
number on a mountain, and the comparative attraction worked
out. Carlini, 1821, obtained a mean density of the earth of
4.84; Airy, 1854, obtained 6.57; Pechman, 1865, 6.13; Menden-
hall, 1880, 5.77; Sterneck, 1883, 4.77, and in 1885, 6.77; Preston,
1892, 5.13.

The Cavendish method. — In this experiment two small balls
are placed at opposite ends of a wire and their movement
measured when attracted by a large ball of known mass. A
comparison is then made between the attraction of the earth
and the attraction of the ball. Cavendish, in 1798, found
5.45 to be the mean density of the earth; Bailey, 1843, secured
5.67; Reide, 1852, 5.58; Corme and Bailie, 1878, 5.5; Wilsing,
1889, 5.56; Preston, Bays and Braun, in 1895 and 1896, all
secured 5.53; in 1902, Burgess obtained 5.55.

The chemical balance has been successfully used by determin-
ing the attraction of a known mass placed above or below the
scale, and comparing with mass of earth. By this method
Poynting, 1891, secured a specific gravity of the earth of 5.49;
and Richarz and Krigar Menzel in 1898 obtained 5.51.

Tides. — The evidence from tides is very simple yet very con-
clusive. If the earth is liquid with a crust or lacking in rigidity,
then the entire crust will yield for a tide; but if it is rigid — as
rigid as steel — there will be some rock tide, but the tidal force
will be largely consumed in raising tides in the more responsive
hydrosphere. Calculations on the height of tides by Darwin^^
and others shows that the tides are exactly what are to be
expected on an earth of the rigidity of steel. Prof. Millikan
has, however, measured tides in the rocks.

^New International Encyclopoedia.
'oQsmond Fisher: Physics of Earth's Crust.
'^Darwin: Tides.

May, 1922 dynamics of the lithosphere 197

Support of load. — Physicists have pointed out that a Hquid
interior would not support continental masses rising 3,600 to
5,400'- meters above the ocean floor.' But probably this argu-
ment is of little value when isostatic measurements have shown
them to be of lower specific gravity.

Relative density of solidified and molton rocks^^ is such that
a crust could not permanently form on a molten sphere in
which convection currents are possible, since solidified rocks
are denser than molten rocks.

Behavior of rocks under pressure. — It is a well-known law
of physics that the melting point increases or rises with
pressure'^ Barus found the rise of the melting point of diabase
to increase directly as the pressure. This would give a melting
point of 76,000° C. at the center of the earth. Under such
pressures as exist at the center of the earth, many physicists
claim, it would be impossible to obtain molten rocks, because
such an adjustment would be necessary as gave the least space,
and it is certain that crystalline rocks occupy less space than
molten rocks do. An increment of temperature increase amount-
ing to about 1° C. for every 18 meters of descent has been
found. Assuming the radius to be 6,268 km., this would give
a temperature of 347,600° C. at the center, which is more than
four times the melting point of diabase under the pressures
assumed at the center. But it is unlikely that such a rate of
increase can be supposed. Deeper borings seem to indicate a
lessening rate, and a point may be attained, perhaps compar-
atively near the surface, where temperature ceases to rise. It
is not our problem to account for the heat. It may be due to
the mechanical work done, to radio-activity, to chemical action,
or compression, or all together.

Another line of experiment giving some possible light on the
condition of the interior of the earth is furnished by those
investigations dealing with the crushing and flowage of rock.
Van Hise'^ states that more than 1,700 kilograms of pressure per
square centimeter are necessary to crush granite.

Fisher^'' has estimated 3,000,000 atmospheres of pressure at
the earth's center.

•^Chamberlin & Salisbury, Text II, 7.

"Fisher: Physics of Earth's Crust.

■■•Chamberlin and Salisbury: Textbook in Geology II, 7.

'^Van Hise: Principles of Pre-Cambrian Geol., U. S. G. S., IGth Annual Report.

"Fisher: Physics of Earth's Crust.

198 O. C. JONES, GEORGE D. HUBBARD Vol. XXII, No. 7

Hayford^'' and Bowie give the crushing strength of granite
as about 1,425 kilograms per square centimeter, which place
the zone of no cavities at ^bout 8 kilometers. Van Hise, work-
ing on this problem, using the crushing point of rock as 1,700
kilograms per square centimeter, obtained adepth of 10,000-
12,000 meters.

GEOLOGIC AND vSEISMOGRAPHIC DATA.

Geologic Climates. — It was the problem of variability of
geologic climate that caused the final overthrow of the Laplacian
hypothesis. There have been in geologic history seven periods
of climatic change. ^^ Four of these have been glacial periods:
the first two, early and late proterozoic, are well down the
geologic column, and indicate a cold climate early in geologic
history not at all reconcilable with a cooling globe, which is
implied by a molten interior. The other periods of climatic
change are the Silurian, Permian, Triassic, Cretaceous, Eocene,
and Pleistocene, of which the Permian and Pleistocene are
glacial.

''Original Crust' \ — The great granite embossments of Scan-
dinavia, Canada, and other countries, formerly believed to
be the exposed surface of the original crust, have been shown
to be but intrusions in older sedimentary rocks, or in some
cases greatly altered sediments. ^^ The fact that there are now no
known exposures of the original crust, certainly none that
could have served as an original source of the sedimentary
rocks — such a lack of original feeding grounds, certainly mil-
itated against the idea of an original crust at all.

It is obvious, too, that if our earth has been built up from
planetesimals which have been gathered in upon a nucleus there
will be no uniform gradation of material in any direction, nor any
zoning into concentric layers so that any one layer will be essen-
tially homogeneous as to density, melting point and composition.
Presumably this heterogenity is not as great as it was ages ago
when the infall of planetesimals was more frequent and when
the larger part of the accretionary accumulation was not so far
remote.

"Hayford and Bowie: Spec. Rept., U. S. C. & G. S.
i^Pirsson and vSchuchert: Text Book of Geo!.
'^Chamberlin, T. C, 1916, .Smithsonian Rpt.

May, 1922 dynamics of the lithosphere 199

This theory leaves no place for a "crust" conception as in the
La Placian theory. But it does make place for enough variation
in the composition and fusibility of earth materials even at the
same depth that given a certain temperature in a zone only parts
will become fluid. Fluid parts might tend to rise toward the
surface. Parts remaining solid must then collapse leaving a solid
zone. This would tend to produce a zonal arrangement of the
earth materials. That such a gigantic banding is not perfected is
shown by the persistence of volcanic intrusion and probably by
diastrophism.

Geographic Distribution of Igneous Intrusion. — A third line of
evidence is that afforded by the extent and distribution of igne-
ous intrusion." Were a molten globe surrounded by a thin crust,
strains and stresses within the sphere would be in large measure
relieved by igneous extrusion. The extent of igneous extrusion
does not seem in any way commensurate with the" stresses that
are found. The localization of its geographic extension to certain
well-defined areas would hardly be expected of lavas extruded
from a molten interior ; and it is therefore unlikely that igneous
phenomena have more than a local and perhaps rather shallow
source.

Seismo graphic Records. — The invention of the seismograph, by
which earth tremors are automatically recorded with the exact
time of their occurrence, has contributed much to the solution of
our problem. From every seismic focus there proceed three sets
of waves : those that travel along the surface and those that pass
through the earth, of which there are two kinds — compressional
and distortional."" Those which pass through the interior
increase in velocity with depth below the surface, and increase
more rapidly than the density, showing that the earth is rigid,
and that its rigidity increases. toward the center. Waves have
never been recorded along a diameter, but as far as they have
passed into the earth's interior, geologists may be sure that the
earth is solid, for transverse waves cannot exist in a liquid and
they are always recorded with the longitudinal (compressional)
waves.

These records have made it possible to get at the depth of
the seismic focus. In the case of the Neapolitan earthquake
103^ kilometers was the calculated depth. -^ The mean depth

sointerior of Earth: Oldham, Q. J., G. vS. Lon., v. G2, 1906.
-^Davidson: Earthquakes.

200 O. C. JONES, GEORGE D. HUBBARD Vol. XXII, No. 7

of the focus in the Ischian disturbance was about 500 meters.,
and of the Andalusian of 1884, 12^^^ kilometers; the Charleston
showed a depth of seven and one-third kilometers, and the
Rivera 18 kilometers. The San Francisco earthquake showed
a depth of disturbance of about 24 kilometers.

Many attempts have been made to measure the velocity of
the waves at the surface, but with such varying results as to
indicate inaccuracy of method or data, or perhaps to some
degree to indicate varying density.

THE DATA OF ISOSTASY."

Isostasy is the theory that any given column of rock taken
from the center of the earth to the surface will have the same
mass as any other column of the same cross-sectional
dimensions. But as density of rocks varies the height of the
column will vary. The inequality of density, however, is
found only in the part of the column near the surface, and the
difference in the length of the column is due to difference of
density in the upper 122 kilometers (77 miles) of the column.
The adjustment of material toward this balance under the
force of gravity is called "isostatic adjustment." Defective
density resulting in a taller column and excessive density
causing oceanic basins, that is, a shorter column, constitute
"isostatic compensation."

The density of any given column is calculated from the
vertical component of the forces operative on a swinging
pendulum or the forces deflecting a plumb-bob. -Corrections
must be made for the effect of topography. The pendulum
method has been found most satisfactory and is generally used.

The scheme followed by the U. S. Coast and Geodetic
Survey is as follows: eighty-nine stations were selected in
the United States, and sixteen over the rest of the world. At
these stations pendulum apparatus is set up, and the vertical
component of gravity worked out. In order to correct for
topography the entire earth is divided into 317 compartments,
and the effect of each compartment computed. These cor-
rections are applied to obtain the actual value of gravity due
to density below the station. Next the value of gravity at
the station is computed, a mean surface density of 2.67 being

22Special Rpt. No. 10, U. S. C. Sz G. S., pp. 6, 7, 108.

May, 1922 dynamics of the lithosphere 201

assumed. The computed density subtracted from the observed
density gives an anomaly which is approximately 1 part error
and 4 parts departure in density from the normal. When
observed density is less than the computed density the anomaly
is negative. The anomalies thus secured bear no relation to
topography.

The following conclusions have been pointed out:

1. The anomalies bear no definite relation to loading and

unloading.

2. The United States is in isostatic adjustment with a mean

departure of 171 m. of rock with 2.67 density.

3. A relation to geologic formation exists by which the

older formations have a positive anomaly.

4. Intrusive and effusive rocks give an anomaly very near

to complete and perfect isostatic compensation.

DATA OF DIASTROPHISM.23

It is hardly necessary to review here the evidence of actual
crustal movement. One might, however, mention a few of the
most important, such as mountain making, folding, faulting,
tilting of lakes, elevated or depressed shorelines with their
familiar accompanying physiographic features, actual measure-
ment of movements, and submergence of oceanic islands.
There was much change of level in and after the Pleistocene
in the Great Lakes region, in Scotland, and in Scandinavia. ^'^

The most noticeable fact of diastrophism is that it is most
intense in regions of thick sedimentation, that is, where geo-
synclines have been filled. The Appalachian geosyncline
presents 12,000 meters of sediment; others have nearly as great
thickness; 10,000 meters are found in the Laramide structure;
3,000 meters of Eocene rocks were deposited in the Rocky
Mountain geosyncline. The Alps present 15,000 meters of
sediment.

Experiments reveal an expansive coefficient of 1 cm. to 19.2
meters for every rise of 100° C. in average rock. In the case
of the Appalachians, 800° at the bottom of the geosyncline
would have given 1650 meters expansion. In Pennsylvania

23The most satisfactory discussion of the facts and theories of this problem is
found in Dana's Manual of Geology, fourth edition.

2nV. B. Wright: Quaternary Ice Age, 1914, pp. 406-426.

202 O. C. JONES, GEORGE D. HUBBARD Vol. XXII, No. 7

the actual shortening lies between 70 and 140 km., thoroughly
beyond the power of increased temperature to create.

Intense normal faulting follows intense folding almost
without exception.

Extensive faulting is usually apparently confined to regions
of thick sedimentation. It is difficult, however, to detect faults
in igneous rocks, also in some metamorphics. This may help
to explain the apparent distribution of faults.

THE CENTROSPHERE.

The term " centrosphere " may be used to include that por-
tion of the earth throughout which rocks are adjustable to
stress through flowage, and in which cavities and fractures do
not exist. It would thus be within the so-called "crust"
or zone of fracture. The seismographic evidence shows two
very important things in regard to this interior; first that it
is solid, because it everywhere transmits transverse waves,
which cannot pass through a liquid — this evidence is conclusive;
secondly, that it is increasingly dense toward the center,
attaining a specific gravity of 6 at .4 radius distance from the
center — evidence calculated from the rate of wave transmission
through the interior. At this rate of progression a density of
8.22 would be attained at the center, assuming the surface
density to be 2.67. It is unlikely that this progression holds
beyond this depth, because the mean density of 5.6 requires a
central density of 11. Down to a depth of .6 radius the
increased density is thought to be only that due to increased
pressure; below this depth the earthquake researches of Oldham^^
may throw some light on the problem. He found that at a
distance of approximately of 130 degrees from the point of
origin, distortional waves were suddenly broken off to be
continued beyond this distance approximately 11 minutes
later. Just what inferences should be drawn from this, it is
not possible to say, except that it is altogether likely that there
exists a central core of about .4 radius extent from the center,
required by other facts to have a density very high, probably
between 8 and 11, and if dense to have a refraction of at
least 2.

Some conclusions may be drawn as to rock flowage through
the centrosphere. Granite has a crushing strength of 1,425

May, 1922 dynamics of the lithosphere 203

kgm. per cm.-^ while the pressure at the center of the earth is
estimated at approximately 3,380,000 kgm. per sq. cm.^^
There can be no question but that rocks under these conditions
will readily adjust to stress or strain. Yet Oldham-^ calculates
that waves emerging at a point 90 degrees distant from their
origin have passed through material having 12 times the
resistance of granite and 15 times its rigidity. He adds: "Prob-
ably this is only what can be traced to increased pressure."

THE CRUST.

The term "crust" is used to describe that portion of the
earth which lies above the level of compensation, and conse-
quently includes all fractures, cavities, and most of the adjust-
ment of the earth's solid substance. Crust and centrosphere
constitute the lithosphere.

Depth. — -Isostatic investigations have placed the compensa-
tion surface — by which is meant the surface at which compen-
sation is complete — at 122 kilometers, which seems by results
obtained to be near the truth; from other evidence the allow-
ance seems ample. Van Hise, assuming the crushing strength
of rocks to be 1,700 kilograms per square centimeter, surface
density to be 2.7, and cavities to be supported by hydrostatic
pressure, found that no cavities or crevasses w^ould be possible
at a depth of 10,000-12,000 meters. Fracture, however, might
occur at this depth. Seismographic evidence would bear out
this conclusion. Most seismic foci lie above 17 kilometers of
depth. In the case of the Neapolitan earthquake, the deepest
estimate fell near 39 kilometers, although the mean depth fell
at 10}/2 kilometers. It is unlikely that this estimate is correct,
because of the imperfect methods of calculation and the
unknown density of the rocks through which the waves passed.
Assuming it to be correct, it is still a very shallow phenomenon
and well within the limits of 122 kilometers. Oldham^* believes
the more or less heterogeneous material may not be more than
a score of miles thick.

"Special Rpt. No. 10, U. S. C. & G. Survey, p. 111.
28Fisher, O.: Physics of the Earth's Crust.

2'Oldham: Some Conclusions as to the Interior of the Earth. Q. J. Geol.
Soc. Lond. (1906), V. 62, p. 456-75; Vol. 63, pp. 344-350.
2801dham, R. D., loc. cit.

204 O. C. JONES, GEORGE D. HUBBARD Vol. XXII, No. 7

De?isity. — Surface density by estimation of its known com-
ponents cannot be far from 2.67. A gradual increase with
pressure due to recoalescence, and compression and inclusion of
gases, due also to the closing of cavities, might be expected.
This gradual increase is supported by seismic investigations.

This topic and many others have been elucidated by the
recent papers of the Chamberlins in Jour, of Geol. Vol. 29-30.

Adjustability. — The most important result of our studies is the
establishment of the fact that adjustment throughout the crust
to external forces or to internal stresses is almost perfect. We
have seen that the variation of latitude occurs because the equat-
orial bulge persists in shifting with the shift of axis. But back of
this wehave evidence of adjustmentin the shape of the earth itself,
which is very nearly the true form of an ellipsoid of revolution.
That it varies at all from this form is evidence, equally good,
perhaps better, of its plasticity. Its apparent inequalities are
the result of its adjustment of heterogeneous density to the
equilibrium of the ellipsoid of revolution. (See note.) We
believe that the whole problem of volcanism, mountain-making,
continent and ocean-basin formations, and all diastrophism are
but phases of the problem of maintaining adjustment to this
form of the earth. That this adjustment is nearly perfect, hav-
ing an average departure of only 171 meters of rock of 2.67
specific gravity in the United States, has been proven beyond
the stage of hypothesis. Even the maximum anomaly or lack
of adjustment found in the United States corresponded to a
stratum only 1,000 meters thick or a deficiency of pressure of
278 kilograms per square cm. or less than one-fifth the crushing
strength of granite. This is an extreme and unusual anomaly.
That this adjustment has been demonstrated in a broad way
in regard to ocean basins and continental masses is beyond
doubt.

The fact that there is essentially no relation to loading and
unloading in the gravity anomalies would indicate rather rigid
adjustment. The quick submergence of volcanic islands having
a positive anomaly is also good evidence. There is no doubt that
the area of deficient density through Nevada, part of Colorado,
Arizona, and Southern California is in a stage of uplift.

Note — By equilibrium is ineant an equilibrium of density, essentially what is
implied in the term "isostasy."

May, 1922 dynamics of the lithosphere 205

Vol can ism P — -The evidence of geographic distribution, extent
of extrusion, and differentiation of magmas indicates that volcan-
ism is a local phenomenon. Seismic evidence clinches the
argument.™ Distortional waves will not pass through a liquid,
yet they pass with perfect freedom through any part of the
crust at which observations have been made. There cannot,
therefore, be any considerable lava lakes beneath the earth's
surface. Isostatic investigations throw an illuminating line of
evidence on the problem. Igneous intrusions and extrusions
of all rocks are almost perfectly compensated.'*^ It would seem
then that volcanism is simply one method of quick adjustment
to the equilibrium figure. It would be found in places of defective
density w^here decreased pressure produces liquefaction in the
form of a vesicle which rises to the surface, and in one way or
another is ejected by force. Most of the vesicles stop before
they reach the surface. Denser material is thereby added to,
or replaces, lighter material bringing about isostatic compensa-
tion. The method would appear to be thoroughly delicate to
reach isostatic adjustment so perfectly. One would expect the
process once set off to continue this inertia beyond the point of
perfect compensation. This is known to occur frequently in the
case of volcanic islands that are thrown up with a positive
anomal}^ but which soon sink into a state of equilibrium.

Moimtain Making. — This is another process resulting from
the tendency of the crustal substance to maintain a state of
equilibrium in reference to the figure of the earth through the
force of gravity. The process is this: Marine sediments are laid
down in a geosyncline, or along the edge of a continent. To
maintain adjustment subsidence takes place until great depths
of sediments are found. Isostatic adjustment is practically per-
fect throughout the process. The sediments thus laid down
have, of course, a lesser density than the sediments or rocks on
either side. There is, therefore, an imperfect horizontal adjust-
ment to the bottom of the geosyncline. Now% as the sediments
are forced downward temperature rises. Probably 800 degrees
is attained at the bottom of the geosyncline, and since it con-
tains rocks w4th more or less water inclusion, the steam devel-
oped, or at least the heated water when pressure is too great

^^Iddings: Problem of Volcanism.

'"Smithsonian Rpt. (1916), The Earth's Figure, etc.

"Special Rpt. No. 10, U. S. C. & G. Survey.

206 O. C. JONES, GEORGE D. HUBBARD Vol. XXII, No. 7

for steam, weakens the rocks, and the expansion caused by
increased temperature, amounting to 1 cm. to every 19.2 meters
for every 100 degrees C. rise of temperature, causes a sHght
disturbance which is carried on by the pressure from the sides;
erosion and deepening of the geosynchne tend to maintain
isostatic adjustment throughout the process. Now inertia may
carry the process beyond isostatic adjustment; certainly the
rock thus thrown up cools to some extent. Both things may
occur; at least there is always a period of normal faulting^-
succeeding a period of folding which might be caused by these
factors. The mountain making process may be aided by lateral
pressure developed by crustal expansion due to rising temper-
ature of the crust. This, however, is mere supposition, and
perhaps unsupported by geologic evidence.

Faulting is another process through which equilibrium is
maintained. It differs from mountain making largely in that
rock flowage and bending are predominant there; whereas
faulting is the result of adjustment with fracture of the rocks
rather than flow. It is not usually associated with the deeper
synclines, although it is confined probably to regions of rather
deep sedimentations.

Causes of lack of adjustment may be external, such as the
tidal influence of the sun or moon, the shifting of the rotational
axis, pressure of the atmosphere, increased load due to forma-
tion of glaciers, or the accompanying emptying of the seas,
great evaporation or excessive precipitation; but probably the
great cause of lack of adjustment is the shift of load due to
erosion.

Earthquakes, so far as is known, present no opposition to our
thesis that all the dynamics of the crust are the result of pro-
cesses of adjustment of heterogeneous density to the form of the
earth through the forces of gravity. The fact that calculations
of depth of focus invariably indicate not a point but a plane
lying more or less vertical to the surface, and that many earth-
quakes actually accompany slipping along a fault plane, would
indicate that the phenomena of tectonic earthquakes are
invariably of this character. The fact that many earthquakes
show merely lateral stresses without elevation or depression in
no way militates against our general thesis. Lateral stresses

'2T. M. Reade: Evolution of Earth Structure, p. 137-8.

May, 1922 dynamics of the lithosphere 207

would be set up in surrounding rocks by elevation or depression
at a distance without local diastrophism. The amount of
accumulated stress resulting in sudden adjustment by fracture
and displacement will depend upon (1) the intensity of the
lateral stresses, and (2) the plasticity of the rocks by which
strain and stress can be adjusted without fracture.

Continental Creep has not entered into our studies. It is
not, however, too much to suppose, since we know the rocks to
be highly plastic, that the difference of pressure on the land side
and water side of the continental slope will result in creep
toward the ocean; the same sort of phenomena that give rise
to mountains. Yet if this is true, the whole process maintains
isostatic adjustment throughout, for anomalies of gravity
nowhere indicate a general excess of gravity along the con-
tinental platform, which lack of adjustment would require.

Some Immediate Causes of Adjustments. — While much of the
evidence presented in this section on "The Crust" indicates
rather rapid adjustment to anomalies, it is true that there would
be no anomalies if the adjustment did not lag more or less
behind the causes which produce maladjustments. This is
only another way of saying that stresses and strains are cumu-
lative, that they may be held by the structures for some time,
but that ultimately the earth structure has failed to hold them,
as shown by Leith.^* If the strains are held a longer time and
become great, their release causes large and widespread adjust-
ments. If the stresses are frequently released, only smaller and
often local adjustments are necessary. When the balance of
stress and structural strength is almost struck, but little is
necessary to start adjustments. Tides, distant earthquakes, or
even changes in atmospheric pressure are believed to be com-
petent to start potential movements.

Deltas furnish a good line of evidence of almost continuous
adjustment, for if adjustment did not take place rather rapidly,
deltas and other areas of loading would indicate a positive
anomaly. A positive anomaly is found at the mouth of the
Hudson and through the Chesapeake Bay region. But we know
that these areas are in a stage of subsidence, so that adjustment,
if not complete, is taking place. On the other hand the delta of
the Mississippi shows negative anomaly, due perhaps to the

2'C. K. Leith, Structural Failure of the Lithosphere, Science, 1921, pp. 195 flf.

208 O. C. JONES, GEORGE D. HUBBARD Vol. XXII, No. 7

tending of physical movements to carry beyond adjustment
through inertia.

Continental masses and ocean basins have been demonstrated
through isostatic measurements to be in isostatic compensa-
tion. This means that the continents and basins must be due
to differential density, and that in this large configuration the
shape of the crust is still in accordance with our thesis. Earth-
quake studies have thrown light on this problem also.^^

CONCLUSION.

We have seen that the phenomena of mountain-making,
volcanism, faulting, and earthquakes, together with density
differentiations, are due to the processes of adjustment, through
gravity of varying mass, to the equilibrium figure of the earth,
and that continental creep and sedimentary loading, especially
in deltas, though not due to this cause, yet are kept in isostatic
adjustment. Our conclusion is therefore as follows: the dynamics
of the lithosphere are essentially the processes of adjustment
of strains and stresses in the varied structures and materials of
the earth, adjustments to the equilibrium form of the earth,
through the force of gravity, involving diastrophism, volcanism,
and gradation.

3<01dham, R. D., Q. J. G. S. London, Vol. 63, 1907, pp. 344-350.

The Ohio Journal of Science

Vol. XXII June, 1922 No. 8

SOME BIONOMICS OF ALPHELINUS SEMIFLAVUS

(HOWARD)*

Chalcid Parasite of Aphids

E. A. HARTLEY
Bureau of Plant Industry, Pennsylvania Department of Agriculture

Contents.

Page

General Considerations 209

Acknowledgments 210

Methods and Apparatus 211

Identity and Description 213

Distribution 213

Bionomics of Adult 215

Reproduction and Development 224

Cohosts 232

Interrelations with Aphidius 232

Secondary Parasites 235

Literature 235

GENERAL CONSIDERATIONS.

Aphelinus semifiavus How. is one of a few species from the
genus Aphelinus, of the Chalcidoid family Eulophidae, known
to attack aphids. The others are scale parasites. At present
there are but seven described species for North America,
recorded as aphid feeders; namely, Aphelinus mali Hald.,
A. nigritus How., A. Semifiavus How., A. Flaviceps How.,
A. Lapisligni How., A. varicornis Gir., and A. automatus Gir.
In addition to this number, the writer has recently taken two
new species: one from an aphid on potato sprouts in the State
Insectary at Whittier, California, and the other from San-
hornia juniperi Perg., an aphid on juniper in Pennsylvania.
Both are being described by Dr. L. O, Howard.

* Contribution from the Department of Zoology and Entomology, Ohio State
University, No. 70.

209

210 E. A. HARTLEY Vol. XXII, No. 8

These parasites, so far as known, are limited to the aphids
as hosts, and most, if not all of them, are confined to a few
species. Aphelinus mail was long considered an exception,
appearing many times in the records as a scale parasite, also.
However, Dr. Howard,* authority on the group, now believes
these records to be in error, and further states that it is probably
not only confined to aphids, but is likely restricted to the woolly
forms, especially the common Eriosoma lanigera Hausm., of the
apple, a species often associated with scale insects; a fact which
may account for the confusion in the records.

The group, on the whole, are extremely minute and incon-
spicuous insects, not often met with by the average entomol-
ogist. Many of the species are quite rare, even to the specialist
on the alert for them. At best they rank secondary to the
Braconid subfamily Aphidinini as a factor in the control of
aphids; although they have been known (Prof. T. H. Parksf)
to play a considerable part in some outbreaks (Toxoptera in
Kansas during 1909). For these reasons, they have practically
escaped attention from a biological standpoint, and most of
them have been known systematically but a few years (since
1908).

With the hope of contributing something to the knowledge
of the bionomics, life-history, economic importance, and rela-
tionship to the aphid complex in general, work was begun on
Aphelinus semiflavus in the greenhouse insectary of the Ohio
State University, Department of Zoology and Entomology, in
the fall of 1920, as part of a thesis for the degree of Master of
Science in Entomology. This was continued throughout the
winter to the middle of May, 1921 ; when the thesis was written.
After graduation in June, part of a series of parthenogenetic
generations of the parasite was taken to Oak Lane, Philadel-
phia, Pennsylvania, where rearing and study was continued at
intervals until the time of this writing, February, 1922.

ACKNOWLEDGMENTS.

The writer here wishes to express appreciation for the kind
assistance of Dr. Herbert Osborn, who directed the work with
many valuable suggestions and criticisms, and to Dr. R. C.

* Private communication,
t Private communication.

June, 1922 bionomics of alphelinus semiflavus 211

Osburn for suggestions and corrections in manuscript. Many
thanks are given to Prof. T. H. Parks for useful suggestions on
rearing methods and recording of data; to Dr. C. H. Kennedy
for aid in microtechnique and drawing; and to the entire staff
of the Department for aid in advice and equipment.

Among those outside the University to whom the writer is
especially grateful, are Dr. L. O. Howard, authority on aphis-
feeding Aphelinids, who very generously gave of his valuable
advice, and assisted greatly in the confirmation of records and
determinations; Mr. A. B. Gahan, of the National Museum,
for determining the parasites; Mr. T. L. Guy ton, of the Penn-
sylvania Department of Agriculture, for determining the aphids;
and Dr. Paul Marchal, director of the Entomological Station,
Department of Agriculture, Paris, France, for giving first hand
his experience in colonizing Aphelhitis mali How. in France.

METHODS AND APPARATUS.

Practically all the data included in this paper are from
indoor rearing, either in a greenhouse or room. Most of it was
carried on in the greenhouse insectary of the Ohio State Uni-
versity, and near a window in room 107 of the Botany and
Zoology building. The observations made in Pennsylvania were
taken on material grown before an open window in the writer's
private room in Oak Lane. That the results thus obtained
should vary with outdoor conditions is a fact which must not
be overlooked; especially since experience has shown Aphelimis
to be quite sensitive to slight temperature changes below a
certain point.

The temperature in the greenhouse insectary varied from
50 degrees Fahr. on cold winter days, to 100 degrees on warm,
sunny days of early fall and late spring. For the greater portion
of the time, it remained between 70 and 80 degrees Fahr. The
room in the Botany and Zoology Building stayed very close to
70 degrees all the time. No temperature readings w^ere taken
for Oak Lane, but here it was very near outdoor temperature
during the summer and warm room temperature (70 degrees
and above) for the winter.

Light and humidity were not measured.

Those cages which gave the most satisfaction in the matters
of light, ventilation, security, and accessibility, were the.

212 E. A. HARTLEY Vol. XXII, No. 8

standard lantern globe cage used in rearing aphids, and a
specially designed celluloid cage. The celluloid cage was found
to be far superior to the lantern globe in ventilation and its equal
in all the other factors. However, both were used with success
throughout the work.

Myzus persiccE Sulz., a common aphid on dock and crucifers,
was used for a host in practically, all the experiments, although
several other species were carried along for the purpose of
testing the parasite in other hosts. This aphid proved to be
quite satisfactory in every way; since it was the natural pre-
ferred host of Aphelimis semiflavus, reproduced readily through-
out the winter on a number of common plants, and was attacked
by practically every other aphid parasite. Dock {Rumex
cripus, and R. obtusifolius) was found to be the best host plant
for this aphid, and was also very satisfactory from an exper-
imental standpoint; being easily grown, and having large smooth
foliage which greatly facilitated observation and handling.

Parasite-free material was obtained by rearing in tight
cages.

In all experiments, a few specimens confined in a small, neat
cage gave better and more accurate results than many in a large
cage. Too many aphids to start with would multiply so rapidly
that they would kill the plant before the experiment could be
closed, making it necessary to transfer them, which always
resulted in loss of material.

For development studies, a number of parasites were con-
fined with parasite-free aphids for a few hours and then removed.
A number of these aphids were dissected at intervals to deter-
mine the stages reached by the parasite in a given time. These
dissections were made in normal salt solution held in a hollow
ground slide under a binocular microscope. Very fine sewing
needles mounted in matches served as excellent instruments.
When the parasites had killed the aphids, they were removed to
gelatin capsules marked with the number of the cage and
date of removal. These were then filed in small cardboard
boxes, by the month, for further reference, in watching their
development from then on. These developments in the capsules
were checked by cage rearing and found to coincide. Gelatin
capsules were made use of as containers for all the material
that was retained for future reference.

June, 1922 bionomics op alphelinus semiflavus 213

IDENTITY AND DESCRIPTION.

Aphelinus semiflavus was first described by Howard ('07)
as follows:

Female. — Length 1.08 mm.; expanse 1.87 mm.; greatest width of
fore wing 0.3 mm. Antenna? short, excluding scape about the length of
face; pedicel long, more than three times as long as wide ; funicle joints
1 and 2 in length and width and each slightly less than one-third length
of pedicel; joint 3 two-thirds length of pedicel and about as wide as its
tip; club slightly swollen, ellipsoidal, and about twice the length of
pedicel. Eyes faintly hairy. General color black; thorax smooth, shin-
ing, scape and pedicel dusky, flagellum pallid, club becoming somewhat
dusky at tip; front and middle femora and all tibiae somewhat dusky;
hind femora straw yellow. Abdomen light yellow shaded around margin
with brownish. Wings rather short, otherwise normal.

Male. — Length 0.85 mm.; expanse 1.58 mm.; greatest width of
fore wing 0.204 mm. Differs from female in having antennae nearly uni-
form brown, scape slightly darker, and in the proportion of third
funicle joint and club. Third joint cylindrical, twice as long as pedicel
and six times as long as broad; club one-quarter longer than third
funicle joint, elongate ovate in shape.

Described from 14 male and female specimens reared by
C. P. Gillette, Fort Collins, Colorado, July 15, 19, 1908, from
Myzus persicse, and reared at Washington from the same host
sent in by Professor Gillette. The parasitized host turns black.

U. S. N. M. type No. 12,931.

DISTRIBUTION.

Geographical.

There are very few available records on the distribution of
Aphelinus semiflavus, but these seem to indicate that it is rather
wide for the United States, at least. Dr. Howard has kindly
furnished the writer with the United States Bureau of Ento-
mology records that he had available, which follow:

Reared from Myzus persicae Sulz., Fort Collins, Colorado,
by C. P. Gillette, July 15, 1908.

Reared from Myzus (new species) on Aguilegia, at Lafa}^-
ette, Ind., by J. J. Davis.

In addition to these, Webster and Phillips ('12) have pub-
lished records from St. Anthony Park, Minn., and Mesilla
Park, N. Mex. The present work will add Ohio to the States in
which Aphelinus occurs. So far it has not been found about
Philadelphia, Pa., after a summer season of diligent search.

214 E. A. HARTLEY Vol. XXII, No. 8

Seasonal.

The data on this point are Ukewise very scant. Practically
all records show that Aphelinus appears rather late in the sum-
mer and fall. The writer did not find it about Columbus until
the first of November, in spite of the fact that he was collecting
aphid parasites there from the middle of September on. Mr.
T. H. Parks*, who was with Webster and Phillips in Kansas
during the work with the "green bug" parasites, is of the open-
ion that Aphelinus does not become numerous until late fall.

Winter is probably passed in the pupal stage within the
blackened remains of the host, according to the observations of
Kurdjumov ('13) working with a similar species in Russia. A
few attempts were made to carry it through the winter in
hybernation cages outdoors in Columbus, but all failed, even
though Aphidius confined with them emerged on the first warm
days of spring. These attempts were repeated the following fall
and winter in Philadelphia with no better success.

As soon as the weather began to moderate in the spring an
outdoor wire-screen cage was established over some dock plants
{Rnmex obtusifolius) in which was placed a colony of parasite-
free Myziis persicce, together with ten or fifteen Aphelinus
semiflavus, to note the behavior of the parasite out of doors at
this season. Observations began on April 11th and continued
every other day until May 13th, and then every few days until
May 24th, when the experiment was closed.

On the first night after the cage was established there
occurred a slight frost which numbed the parasites for a time,
but they became active again as soon as the sun came out.
Several warm days followed, with rather cool nights, and then
about a week of cool rains followed by more warm days.

Several parasites were observed in the cage among the
aphids for three or four days, when they disappeared. On the
25th of April, one live Aphelinus was again observed in the cage
ovipositing in the aphids. Observations were made on this one
intermittently until May 20th. The aphids multiplied rather
slowly for the first ten days in the cage and then gradually
recovered their normal rate, producing a good supply of young.

* Private communication.

June, 1922 bionomics of alphelinus semiflavus 215

In spite of the fact that live parasites were confined with
these aphids for over a month during a period of rather mod-
erate weather conditions, none of them showed the character-
istic blackened appearance of parasitism.

On May 5th, fifteen aphids were dissected and one parasite
egg found, w^hich appeared just ready to hatch. Later observa-
tions, however, showed no sign of parasitism. On May 20th,
more aphids were dissected in which were found three or four
well grown larvae, apparently normal. On the twenty-second,
one aphid had turned black. This was the only one of the lot
turning by May 24th when the experiment was closed.

While the above observations are rough and incomplete,
they more than suggest a considerable influence of weather con-
ditions on the activity and development of Aphelinus.

Where conditions are favorable, Aphelinus will multiply
throughout the year; the generations following each other in
cycles of 20 to 30 days, depending largely on temperature.

BIONOMICS OF ADULT.

Emergence.

Emergence takes place through an irregular rounded hole
cut on the posterior-dorsal side of the blackened host remains.
The fact that the emergence hole is always cut in this one par-
ticular spot, is due to the peculiar orientation of the parasite
in respect to the host; the main axes of the latter being exactly
vice versa to those of the former, which always bring the
mouthparts of the parasite in this one position.

Locomotion.

Movement is rather sluggish in Aphelinus compared with
other aphid parasites. Unless disturbed, it usually crawls delib-
erately about among the aphids. At times, however, it was
observed to hop from one leaf to another, or from the side of
the cage over onto a plant. When stimulated with a needle, it
will hop away much like a flea; taking short jumps of two or
three inches. Many attempts were made to goad it into sus-
tained flight, but all were unsuccessful. In every case, it would
slant downward, even when held several feet above a piece of
white paper before a window. The wings are slightly reduced,

216 E. A. HARTLEY Vol. XXII, No. 8

and probably are not capable of sustaining it in flight at all.
On the other hand, the legs are well developed.

The above evidence would tend to discredit Aphelinus where
rapidity of dispersion was a prerequisite for efficiency, but Mr.
H. S. Smith and Harold Compere ('20) have pointed out in
their work with Aphycus lounsburyi, an imported parasite of the
black scale in California, that this is a trait in the parasite's
favor where it is for local distribution by man.

Reactio7i to Light.

The adult Aphelinus is slightly positive to light, but- it does
not become quiescent in darkness, as shown by several exper-
iments to determine the effect of light on oviposition, which
will be taken up in detail under that heading.

Oviposition.

When the attention of Aphelinus is directed toward an aphid
for oviposition, it moves with extreme precaution and delibera-
tion; approaching very slowly and steadily, swaying from side
to side and feeling forward with the antennae. Just before the
antennae touch (in some cases they do touch) , it halts its forward
progress, sizes the situation up carefully from short range,
obliques slightly, turning the head toward the aphid with a
last parting look as if to make sure of the aim, position, etc.,
and then suddenly faces about, rising well up on the legs,
thrusts the ovipositor out and downward with three or four
quick backward strokes toward the victim. In the majority of
cases, these miss the mark, either by the aphid moving or
through poor aim. Usually they fall short and the point of the
ovipositor is brought down on the substratum on which the
aphid rests. If the host is in an advanced stage, the parasite
may have difficulty in piercing the integument. In either case
after about three or four thrusts, it will turn and repeat the act,
or crawl away in search of a more favorable victim. However,
if successful, it remains in position, standing well up on the legs,
the ovipositor thrusts out and downward, with just the tip
inserted in the host. (Plate I, Fig. 2). This position is often
maintained for several minutes. In fact, some were observed to
last as long as fifteen minutes, and repeated twice in succession
for a like period without depositing a single egg.

June, 1922 bionomics of alphelinus semiflavus 217

In the majority of instances, the aphid appears undisturbed
while oviposition is going on. This is especially true of the
younger stages. However, there are times when the slightest
touch with the antennas or a prick with the ovipositor will cause
them to kick up and make off. If this happens when the ovi-
positor is fastened in one of the larger stages, it drags the par-
asite with it. If the host is smaller, however, the parasite is
able to master it and keep it in place in spite of its struggles.
This is done by the parasite standing well up on its legs and hold-
ing up the victim slightly so that it cannot get a firm foothold on
the substratum. The ovipositor is held in place during the
struggle by the presence of three retractile barbs near the tip.
These function so efficiently that the parasite itself often has
difficulty in getting free, often having to brace the hind legs
against the aphid and give several vigorous pulls before it is
withdrawn. At times, the ovipositor may be fixed so firmly in
place that it permits a larger host to drag the parasite about
so violently that injury results. Several times Aphelinus has
been observed in a crippled condition after getting free from
one of these encounters. In this condition, the ovipositor remains
extruded, the parasite not having the power to retract the
abdominal segments that bring it back in position, and the
individual goes stumbling off with head down and abdomen
elevated until it topples over apparently dead.

The ovipositor is usually inserted on the dorsal surface of
the host's abdomen, but almost any other part of the body may
be chosen, depending on the point of approach. Many times it
has been observed on the head between the antennas, and
among Macrosiphum pisi on clover, a large species that stands
at a considerable angle from the plant, well up on its long legs,
the parasite was observed to attack it from beneath, elevating
the ovipositor well up and making contact with the ventral
surface of the abdomen.

Stage of Host Preferred. — A distinct preference was early
shown for the younger stages of aphids. In order to determine
this more exactly, several experiments were planned and carried
out. Some difficulty, however, was encountered in eliminating
a number of factors that might alter a true expression of this
preference. These factors were the variation in numbers of the
different stages available for oviposition ; the high mortality of

218

E. A. HARTLEY

Vol. XXII, No. 8

the first and second stage nymphs after being parasitized; and
the difficulty of handling large numbers of the various stages of
aphids necessary to obtain accurate results.

At first a large number of parasites were placed with a
greater number of aphids, in the different stages, for a short
time and then removed. An equal number of aphids, represent-
ing the different stages, were then isolated and the parasites
allowed to develop in these until they showed externally. These
parasitized individuals were then counted and the percentage
taken to indicate the preference of the parasite for a given stage.
(See Table I.).

Table I.

Showing the Percent of Parasitism in the Various Instars of the Aphid Host, Reared
Through Until It Appeared.

No. Aphids Used

Instars

No. Parasitized

Percent.

100

100

75

1-2
2-3

4-adult

26

16

5

26
16
6.6

This method was unsatisfactory, as it did not account for the
death of a large number of the smaller stages, which would lower
the percentage considerably for that group. It also did not
necessarily provide an equal number of the various stages,
either at the beginning or the end, to eliminate chance. Then
finally the separating and keeping the aphids in dift'erent cages
for any length of time always made possible the death and
escape of many specimens that could not be accounted for.

To get around these difficulties, the following modifications
were introduced: As nearly equal and smaller numbers of the
different stages were placed together with a number of par-
asites for a day or so and then all were dissected. The percent
parasitized in the various groups, as indicated by the presence
of the parasite's egg, showed fairly accurately the preference for
that particular stage. Three separate lots were thus treated
with the results shown in Table II.

The extreme rarity of parasitism in the adult aphids was
clearly demonstrated in the experiments to determine the effect
of parasitism on the production of young, in which it was neces-

June, 1922 bionomics of alphelinus semiflavus

219

sary to bring about a parasitized condition in the adult after
she had started to produce young. Out of many trials to bring
this about, but three were successful; notwithstanding the fact
that several parasites were confined for days with the adult
aphids time and again.

It is believed that several factors operate here to determine
this preference for the younger stages of the host; namely
(1) size, it being easier to ovipost in a small aphid than a large
one, due to position alone; (2) irritability, the large aphids are

Table II.

Showing the Percent of Parasitism in the Various Instars, Dissected Immediately
After the Parasites Were Removed.

Approx. Instar

No. Dissected

No. Parasitized

Percent Parasi-
tized

Lot 1

Lot 2

Lots

Lot 1

Lot 2

Lots

Lotl

Lot 2 Lota

1-2

90

105

42

54

58

19

60

55.7

45.2

3-4

161

84

57

66

26

20

41

31

35

4-5

62

61

19

10

4

1

16

6.9

5.2

more irritable than the small nymphs, which often renders ovi-
position impossible; and (3) toughness of the integument which
makes it difficult for the ovipositor to penetrate.

Number of Eggs per Host. — In more than 3,000 separate dis-
sections for egg counts, etc., there were only two or three cases
where more than one egg was deposited in a single host. These
few exceptions occurred only where a number of parasites were
confined with a few aphids for several days, and even then no
more than two eggs were ever found in a single host. In some
of these trials a parasitism of 100 percent was obtained for 20
first to third instar nymphs confined with one parasite for a
single day of twelve hours. Instances were observed several
times where parasites apparently oviposited in hosts already
parasitized, even to the blackened condition; but in no case
did subsequent dissection show that an egg was deposited.
Aphelinus has also been observed to return several times to a
single host, but here, likewise, only a single egg is left, or ia
many cases none at all.

220 E. A. HARTLEY Vol. XXII, No. 8

The above observations seem to indicate that Aphelinus
places but one egg in a host, but that it is incapable of deter-
mining whether a given host harbors a parasite already until
the ovipositor is inserted. The above habit is decidedly in its
favor when its efficiency as a parasite is considered in contrast
to some of the more wasteful species like Aphidius, which gen-
erally places a number of eggs in a single host, but only one of
the resulting larvae matures.

Number of Eggs Laid per Day and Night. — To determine
the number of eggs laid per day and night over the period of
egg production, experiments were carried out with a single
Apheliniis confined with a given number of nymphs from the
first to the third instar. Dissections were made on these both
in the evening and morning, and a fresh supply of parasite-free
aphids placed in the cage for the parasite to oviposit in for the
succeeding period. During the night, the cages were kept in a
dark chamber so that practically absolute darkness prevailed
until the time came to change to light. As nearly equal periods
of light and darkness were obtained as was possible; likewise,
other factors, such as temperature and humidity, were fairly
uniform. All experiments were carried out in room 107 of the
Botany and Zoology Building, in a temperature of from 70 to
75 degrees.

Owing to the extreme minuteness of the specimens dealt with,
considerable difficulty was experienced in carrying a single
parasite through its total life without its escaping or being
accidently killed in handling. This was so great that only one
specimen went through its total period of egg production to a
natural death. Two others were carried for seventeen and
eighteen days respectively before they escaped or were acci-
dentally killed. The results of these experiments appear
graphically in Figure 1.

Feeding.

It is quite evident from observations made that the com-
monest means of sustaining life in the adult Aphelinus is by
its habit of feeding at the puncture holes made by the ovipositor
in the young aphids.

This habit is not restricted to Aphelinus alone, but seems to
be rather common among chalcid parasites in general. The

June, 1922 bionomics of alphelinus semiflavus

221

records with which the writer is familiar date from Howard
('08), where he quotes Dr. Marchal's observations on this habit
in the parasite TetrasHchus xanthomelcBfice Rond, on the eggs of
the elm leaf beetle Galerucella luteola. Later Howard ('10) in
a more general article on this habit among the Chalcidoidea,
again refers to Marchal's observations on TetrasHchus, in addi-
tion to some similar observations on Aphelinus mytilaspidis in
Aspidiotiis ostrecBJormis, along with several others; namely,
Dr. H. T. Fernald on TetrasHchus asparagi, feeding on the eggs

*vtfa"l'i-?Vl''5"t-gi r' g'l '9\lo\h'Uk\l3\MU9\»-l7^ls\k^'l^^

LdXPerfodaf 17 dags
Av'er'age. per vlght 6

" 24 hrs. 153 __
Total egijs prDduc€d _ 256 ^

m Period. cfZC days
A'/eragz pgr mght 62 z
■ -____. "_ day... lg.Z ^

VThtd^ ggg^tpf-c^fjifad 507. _

^miA.

I3:,:i££aLiL

J__FM£^

Fig. 1. Number of eggs deposited by a single Aphelinus semiflavus per day and
night for a given period. Black equals night, cross lines equals day; large squares
on abscissa equal 24 hours; small squares on ordinate equals one egg; "x" equals
point where natural death occurred.

of the asparagus beetle {Crioceris asparagi), and Mr. J. G.
Sanders concerning Aphelinus fuscipennis on Aspidiotiis rapax.
Mr. H. J. Quayle ('10) also refers to a similar habit as occurring
rarely in ApheUnus diaspidis, parasite of the red or orange
scale {ChrysomphaJus aurantii) in California. He also observed
this species to feed on honey dew, plant juices, and fruit. Mr.
L. P. Rockwood ('17) published for the first time observations
on this habit in ApheUnus lapisligni How., feeding at the

222 E. A. HARTLEY Vol. XXII, No. 8

puncture holes in Aphis bakeri, in which the actions are described
in some detail.

A number of the above cited observations have been ver-
ified, by the writer, on Aphelinus semiflavus, and additional data
have been secured on this interesting feeding habit.

These parasites confined in glass vials or other receptacles
without food or water were noticed to live but two or three
days at most; while those among aphids lived a much longer
time (two weeks or more). This species had also been observed
feeding at the puncture holes made by the ovipositor in aphids.
In addition to this aphid-feeding habit, the writer was interested
to know whether they fed on any other substance, and if so,
how long they would live on the various kinds of food that
might be available. This point was thought to have consid-
erable bearing on methods of handling and transporting species
to be used in an economic way for the suppression of injurious
forms.

Several experiments were undertaken to test out the effect
of various foods on the length of life of adult Aphelini. Spec-
imens emerging at the same time were placed in cages as follows :
One lot on dock {Riimex obtusifolius) only, in a lantern globe
cage; another with four or five large aphids not yet producing
young; still another on a dock plant to which leaves covered
with honey-dew were added every other day; and lastly, a lot
on a plant with honey solution added every day. All were con-
fined in lantern globe cages with growing dock plants in room
107 of the Botany and Zoology Building. The results appear
in Table III.

Some careful observations were made on Aphelinus semi-
flavus in the act of feeding at the puncture holes made by its
ovipositor in aphid nymphs. To confine the specimens so that
they could be easily observed under a binocular microscope,
two hollow ground slides were used with the aphids and parasite
in the space between them on a bit of leaf. Four or five 2-instar
nymphs were thus enclosed with one female Aphelinus. Ovi-
position began immediately after they were placed together,
and was repeated several times in the same aphid, after which
the victim was noticed to droop down in a sickly condition. In
this state the parasite approached and carefully examined the
aphid with its antennae. Being apparently satisfied, it placed its
forefeet on the victim's back and its mouthparts to the puncture.

June, 1922 bionomics of alphelinus semiflavus

223

This position was then held for several minutes without mov-
ing, during which the body of the aphid was noticed to slowly
collapse. After it was apparently sucked dry, Aphelmus would
withdraw and search out another victim where the same
maneuvers were repeated. Three small nymphs were thus fed
upon in half an hour, after which the parasite's abdomen
appeared quite distended with their contents.

These dead aphids were later dissected, and it was found
that Aphelinus had deposited an egg in each. This would seem
to indicate that oviposition was the primary object in punctur-
ing a host, and that feeding was a secondary, acquired habit.

Table III.
Effect of Different Food, Accessible, on Length of Life in the Adult Parasites.

Food

Number of
Parasites

Length of Life

3
3
3
1

3 days

4th instar aphids

Honey-dew (on leaves)

Honey solution (fresh)

4 days

11-12 days

39 days

However, with this habit of feeding, the parasite defeats its
primary purpose by killing the host and preventing the develop-
ment of the egg immediately after it is deposited.

Observations made in the course of other experiments show
that a single parasite ordinarily kills, in the above manner,
from three to five of the smaller instars per day. The very
young stages are almost always preferred, although it has been
noticed to feed on a third or fourth instar nymph. That the
older stages are seldom if ever attacked, has been demonstrated
in a number of instances where Aphelinus was confined with
adult aphids for various purposes. The parasite not only failed
to oviposit in these adults, but actually died with them for
want of food when the adult aphids did not produce young for
it to feed on. In all cases the aphid is very much weakened so
as to offer practically no resistance, before the parasite will
attempt to feed. While the feeding is going on, the aphid

224 E. A. HARTLEY Vol. XXII, No. 8

remains slumped down apparently oblivious to the slow ebbing
away of its life blood, the only movement being a slight wave
of a leg or antenna.

Length of Adult Stage.

The length of life in the adult has been observed to vary
according to the kind of food available. Temperature also is
undoubtedly an important factor, but no accurate experiments
have been attempted to show how it operates.

The effect of the different kinds of food on the length of life
is shown in Table III, and may be briefly summarized as
follows: Confined without food, on plants alone, among older
aphids on plants, or in small receptacles, death ensues in less
than four days; on honey dew they live for twelve days; and
one specimen was kept alive for thirty-nine days on honey solu-
tion in distilled water, given fresh every day until it finally
escaped. There is reason to believe that they will live much
longer on this. The only one carried through to normal death
on aphids, lived thirty-six days; producing eggs for thirty of
these days.

REPRODUCTION AND DEVELOPMENT.

Method.

The prevailing method of reproduction in Aphelinus semi-
flavus, as well as in a number of other chalcid parasites, is by
parthenogenesis. Seventeen successive generations have thus
far been reared parthenogenetically, and there is every reason
to expect many more to follow indefinitely; since the last
offspring appear as vigorous as the first.

Proportion of Sexes.

Males are quite rare in this species. Out of more than 900
individuals examined from the different generations through-
out the series of parthenogenetic generations, but seven males
were found. These were scattered more or less irregularly
through the series as shown in Table IV. It is quite possible
that males might have appeared from time to time in other
rearings and passed unnoticed, due to the difficulty of dis-
tinguishing the sexes without a microscope. However, through-
out all the observations, of either living or dead material, males

June, 1922 bionomics of alphelinus semiflavus

225

were encountered but one other time, when three were taken
from Cage 48a3 on March 2, 1921. One of these was confined
with females among some aphids on a dock leaf in a small vial,
and copulation was observed. No observations were made on
mated females to determine whether mating had any effect on
the proportion of sexes and number of offspring produced. This
must be left for later investigation.

Table IV.

Sample Counts from a Series of Partheno gene tic Generations Showing Proportion

of Sexes.

Generation

ai

bi

Ci

d2

ei

fi

g2

hi 12

J2

ki

li

ni2

rii

Oi

pi

q2

Date

3-6

1921

3-22
1921

4-3
1921

5-4
1921

5-23
1921

6-7
1921

6-23
1921

6-29
1921

8-11
1921

9-1
1921

9-24
1921

9-20
1921

10-30
1921

11-19
1921

11-27
1921

12-13
1921

1-30
1922

No. Females. . .

66

38

61

135

55

59

15

8

132

113

81

6

74

57

1

12

8

No. Males

0

0

0

3

0

0

0

0

0

1

3

0

0

0

0

0

0

Some of the Encyrtidae, a family of scale parasites, closely
related to the Eulophidae, produce but few males or none at all.
In other species of the genus Aphelinus, feeding on aphids, the
males are not known.

The production of females parthenogentically that are
capable of producing more females in the same manner, for an
indefinite number of generations, is a very valuable asset to a
parasite when it is to be established in new territory. By this
method of reproduction the chances of its increase are greatly
enhanced. Likewise, it is less liable to die out through reduction
in numbers and consequent scattering of individuals that
would reduce the chances of mating where this was important
for the perpetuation of the race.

The Egg.

Description. — The egg is elongate ovate, and slightly bent
in the middle, with dimensions of .21 x .05 mm. The anterior
end is slightly more rounded than the posterior, which tapers
bluntly to a point. At the anterior end, there also appears a
small nipple-like micropyle that projects just far enough from
the surface to be seen with a high power compound microscope.
The color, in reflected light, is a very light cream-white; darker

226 E. A. HARTLEY Vol. XXII, No. 8

in transmitted light. The corion is very thin and transparent;
showing the finely granular structure of the contents, which is
homogeneous throughout for a few hours after the egg is laid.
Soon development begins to appear by the characteristic form
of the growing embryo. At the end of twenty-four hours the
egg clears up slightly, except for certain parts of the embryo,
which show darker in the form of two blotches; the one in the
anterior portion of the egg having a long and wavy form which
bends around like a hook near the end of the egg; the other in
the posterior portion is more rounded. Both of these blotches
finally join together by the growth of the mesenteron, shown by
two faint lines. When the egg is forty-six to forty-eight hours
old, it becomes still more transparent, and only one elliptical
dark spot appears near the center. It is now almost ready to
hatch. (See Figs. 3, 4, and 5, Plate I.).

Position in Host. — The egg floats loose in the hsemocoel of
the host, where it may be seen on dissection under the high-
power of a binocular microscope. It is quite large in size
compared with the size of the adult.

Length of Stage. — The period of time spent in the egg stage
is very near three days (72 hours) for all the observations.

Number Laid. — The only actual count made of the number
of eggs laid by a single individual in the course of its life, gave
507. (Fig. 1). Other partial counts would lead one to believe
that this is a good high average. The conditions under which
the eggs were deposited may be considered almost optimum,
since the parasite was closely confined with a number of par-
asite-free aphids of the most desirable stage. It is difficult to
make an estimate of what the total number would be under
more natural conditions out of doors, but it is probably much
less than the actual counts indicate for caged material. From
the number of blackened aphids obtained from the different
cages, one might estimate the total number parasitized by
one adult female to be around 200.

Like many other parasitic Hymenoptera, there are only a
few mature eggs in the ovarian tubes at a time; about ten for
Aphelinus. The other eggs mature from day to day in such
numbers as required, which is probably regulated by some
external stimulus, like the presence of a large number of hosts.

June, 1922 bionomics of alphelinus semiflavus 227

Larva.

Description. — The larva when first hatched has practically
the same size and form as the egg, but slightly shorter and
broader. As growth proceeds the anterior and middle segments
enlarge to accommodate the increasing mesenteron, giving it
at first a spindle form and later a distinct top shape; the head
forming a knob on the broad rounded anterior end, and the
posterior tapering to a rounded point. When the larva reaches
maturity it is contracted more in a longitudinal direction,
becoming almost globular in general shape. (Fig. 7, Plate I).

In the younger stages the color is almost absent, except the
dark mesenteron which stands out against the general trans-
parency. Later on the accumulating fat body lends a light
yellow color to the larva.

The segmentation of the larva is rather obscure, but with
careful search thirteen may be counted. The head is distinct,
supported by a visible tentorium, and bearing a mouth opening
in the anterior ventral portion. This mouth is armed with two
sharp dark mandibles which are situated well back in the cav-
ity, but are capable of protrusion sufficient for grasping pur-
poses. A peculiar botryoidal structure may be also observed
covering the front and vertex. (Fig. 8, Plate I). This is prob-
ably a group of sensory organs. The entire digestive tract may
be traced from mouth to anus in transmitted light; though
the fore and hind guts-are indistinct. Several other internal
organs were slightly visible, but no attempt was made to iden-
tify them. Spiracles are observable on segments five to nine
inclusive, but could not be seen on any of the others. Small
trachcce lead off from these, but it was not determined whether
they function or not.

Position in Host. — During most of the growing period the
larva occupies no definite position in the host, but moves
freely about in the fluid of the body cavity. However, when it
has devoured most of the internal organs of the host and has
become large enough to fill the abdominal cavity it assumes
a position with its primary axes similar to those of the host.
Just before pupation this position is exactly reversed, so that
the primary axes of the parasite are opposite to those of the
host, both anterior-posteriorly and dorso-ventrally.

228 E. A. HARTLEY Vol. XXII, No. 8

Length of Stage. — The larval period varies from about six
to eleven days, or even longer in some cases where the temper-
ature is low. The usual time from egg deposition until the
aphid host turned black, was nine to ten days. Pupation began
within one or two days after the host turned black, and by the
end of three days the last larval skin was cast and the full pupal
form assumed.

It was found that it took two days longer for the larva to kill
and turn black an adult aphid than it did for a third instar
nymph, and one day longer for a first instar nymph than for a
third instar. This would seem to indicate that the medium
instars furnished optimum conditions for the development of
the larva, where other factors were equal.

Pupa.

Description. — The pupa is characteristic of the Hymenoptera
in general, i. e., of a form similar to the adult, with rudimentary
wings, and large turgid legs and antennae lying near the body on
the ventral side, and enclosed in transparent sheaths. When
first formed the pupa is almost transparent or very light yellow
throughout. Soon the eyes turn to a reddish brown and the
light yellow deepens with age until the colors of the adult are
reached at maturity.

Meconia. — As soon as the pupa begins to take form, or just
before it sheds the last larval skin, it voids several brown bodies
of an oval shape. These are the characteristic meconia of the
parasitic Hymenoptera, and represent the total, larval excre-
ment that has accumulated throughout the period and dis-
charged at this time.

Position. — The position of the pupa with reference to the
host is exactly opposite to the primary axes of the latter, the
same as described for the mature larva. This places the mouth
parts of the adult Aphelinus in a position to gnaw out the
emergence hole on the posterior-dorsal surface of the blackened
host remains.

Length of Stage. — The average length of the pupal stage is
seven to eight days, but it may vary between five and fifteen
days, or even longer under adverse conditions. There is every
reason to believe that it passes the winter in this stage.

June, 1922 bionomics of alphelinus semiflavus 229

Effect of Parasite on Host.

On Internal Structures. — As soon as the young Aphelinns
larva hatches, it begins feeding on the fat body and developing
young of the host. Within three or four days after hatching
nearly all the young aphids within the mother are destroyed.
The feeding continues on the other structures, until nothing is
left, when the parasite larva approaches maturity, but the
digestive tract. This is in common with the habits of other
parasitic Hymenoptera larva which spare the vital organs of the
host until the very last.

The larva of Aphelinus is armed with well developed man-
dibles, which, however, do not project out of the mouth as in
the larva of the Braconid parasite, Aphidius; but seem situated
back in the mouth cavity where they are less effective in tearing
up host tissue. There is no gathering of bunches of fat globules
in a host parasitized by Aphelinus, as in one harboring Aphidius,
which would indicate that the fat cells are not broken down.
However, many bits of tissue and separate cells may be observed
floating promiscuously around in the body fluids of a host
parasitized by Aphelinus.

On Exter?ial Appearance. — The first external appearance of
parasitism is a change in color of the host from green to light
cream. Then a honey-colored spot appears in the abdomen,
which is the darker mesenteron of the larval parasite within.
This light color of the host deepens into a yellow or light amber
in another day, and by the following day begins to turn gray.
Within a very few hours after graying begins, the aphid is coal-
black, except for the head and appendages, which are trans-
parent. Death occurs during this last darkening. Just before
death the aphid spreads out its legs in symmetrical form and
firmly grasps the plant on which it rests. This tends to make
them adhere to the plant after death; still, they are further
secured by some form of silk secretion through the ventral wall.
No detailed observations were made on this act, but it is evi-
dent that no hole is cut through, as in Aphidius. Perhaps only a
very small puncture is made and the silk forced through it.
The amount is very small, at most, and in some cases there is
not enough to detect; nevertheless, the black aphid remains
adhere quite firmly to the substratum.

230 E. A. HARTLEY Vol. XXII, No. 8^

On Production of Young. — Several experiments were under-
taken to determine the effect of parasitism in the various instars
on their subsequent maturity and production of young. An
equal number of parasites were confined with separate lots,
of different ages and instars of aphids for a day and then
removed. The aphids were observed until they showed para-
sitism and died. One nymph, parasitized on the day it was
born, carried the parasite through to maturity, but did not
mature itself, or produce any young. Three nymphs, para-
sitized in the second instar, produced but one young, which
was doubtfully from one of these nymphs, since another unpar-
asitized one occurred in the same cage. Nine second instar
nymphs matured and produced but two young at the end of
eleven days from birth. Seven nymphs, parasitized in the third
instar, matured and produced sixteen young before succumbing
to the parasite. With the larger stages, parasitism was so rare
that no data were obtained.

It appears from these experiments that those aphids par-
asitized in the second instar seldom mature and produce young;
while those parasitized in the third instar may mature and
produce several young before they are killed.

In the few cases where adult aphids were parasitized after
they had begun to produce young, the production continued for
six days from the time the parasite's egg was deposited. During
this time two females produced twenty-five young. Allowing
three days for the egg of Aphelinus to hatch, it will be seen
(Fig. 2, curve "d") that the decline in production of young
began shortly after the egg hatched. Production ceased alto-
gether two days before the death of the host.

Aphelinus may also disturb the production of young in
aphids by worrying or exciting the viviparous females. This
is shown in Figure 2, curves a, b, and d, between the points
x and xi where the parasites were introduced and removed. In
every case a marked drop occurs in the production. However,
as soon as a few young are born, the parasite's attention is
directed to them so that the adults may go on producing others
unmolested. Here is where the preference of Aphelinus for the
younger stages of the host is of marked significance as a factor
in their control, since it does not attack at the source of pro-
duction, the adult female. This may account for the fact that
Aphelinus is much slower than Aphidius in exterminating a
colony of aphids with which they are confined.

June, 1922 bionomics of alphelinus semiflavus

231

Effect of Host on Parasite.

As in common with most parasitic Hymenoptera, there is a
great variation in size of adults according to food supply or
size of host. This was more than double in Aphelinus, or from
.35 mm. to .75 mm. in length. The extremely small specimens
were apparently sterile, for several trials on parasite-free
nymphs failed to get them to reproduce, or even lay eggs. An
attempt at oviposition was noticed in one case, but the parasite
was unable to extrude the ovipositor its full length.

Fig. 2. A series of curves shoiving the effect of the parasite Aphelinus semiflavus
on the production of young in adult viviparous Myzus persicce. a. Average daily pro-
duction of young in six females for the average total period of production, with
Aphelinus but unparasitized (note drop in curve between x and xi when parasites
were introduced, showing effect of the presence of Aphelitius on production of
young); b. average daily production of young in ten females for the average total
period of production with Aphelinus but unparasitized. (note drop between x
and xi as in a); c. average daily production of young in ten females free from par-
asites; d. average daily production of young in two females for the average total
period of production before and after parasitism. The parasites were introduced
at the point x and removed at Xi. Death from parasitism occurred at the end of
he curve.

232 E. A. HARTLEY Vol. XXII, No. 8

COHOSTS.

Previous records give Myzus persicce Sulz., Aphis gossypii{?)
Glover, Aphis maidis Fitch, and Chaitophorus viminalis Mon.,
as hosts for Aphelinus semiflaviis . The writer can add to this
list from his own rearings, the following: Macrosiphum pisi
Kalt., M. granarium Kirby, M. Sanborni Gillett, rarely, and
Anur aphis viburnicola Gillett.

Myzus persicce, from which most of the field records come,
seems to be the preferred host, although it took to Macrosiphum
granarium and Anuraphis viburnicola quite as readily in cap-
tivity. Macrosiphum pisi was not parasitized very heavily, due,
perhaps to its long legs and large size, and irritability. Macro-
siphum sanborni escaped almost entirely for no apparent reason.
They were only rarely attacked even when confined in a cage
with a number of parasites, and a colony went through the
winter in the greenhouse among many parasites with but a
scarce eight or ten being parasitized.

Several attempts were made to rear Aphelinus in Aphis
rumicis, another common dock aphid, but all were unsuccessful.
The parasite would oviposit in them freely, and subsequent
dissection showed that the eggs would hatch and the larva
become nearly half grown, in some cases; but they would always
die before reaching maturity. In most cases death occurred
shortly after the egg hatched.

INTERRELATIONS WITH APHIDIUS.

Considerable importance has been attached to the inter-
relations of primary parasites in a single host, since the dis-
covery by Pemberton and Willard (18) of the disastrous results
of the interrelations of two primary fruit fly parasites imported
to the Hawaiian Islands.

From what is known of the two groups of primary aphid
parasites, there seems to be no question about the superiority
of Aphidius over Aphelinus as a controlling factor for aphids.
It not only appears earlier in the season, but lays more eggs in
a shorter time, is more vigorous in its actions, is not confined so
closely to the younger aphids, and has a much greater dispersal
than Aphelinus. It was, therefore, both interesting and
important to determine to what extent these two occurred in
the same host, and the ultimate outcome of such occurrence.

June, 1922 bionomics of alphelinus semiflavus 233

Observations on colonies of aphids in the open greenhouse
among both Aphidius and Aphelinus showed that parasitism of
a single host by both parasites was rare at best, if not entierly
absent. In fact, it was often difficult to bring this about when
they were confined in a small cage. However, when they were
put in and taken out separately, the one before the other, results
were different. Aphidius would parasitize practically every
aphid in a small colony, and all the eggs that Aphelinus would
deposit later, which was always considerably less than Aphidius
for a given period, would be in the same host with one or more
Aphidius eggs or larvae.

When Aphidius was placed with a colony of aphids a day
ahead of Aphelinus and remo^^ed before Aphelinus was intro-
duced, a heavy parasitism by both resulted. But in practically
every case, the Aphelinus eggs failed to hatch. The conditions
were then reversed, and Aphelinus was given a day's start. In
this case Aphelinus hatched and began development in the
usual way, but they did not interfere in the least with Aphidius
which came along later. This very efficient parasite emerged
from its membraneous cover in the normal manner and within
a day or two the small Aphelinus larva would die. This happened
even when the Aphelinus larva was allowed several days the
advantage over Aphidius and was quite large when the latter
hatched.

It was, therefore, practically established that for the younger
instars, at least, Aphidius would always dominate, regardless of
whether it came before or after Aphelinus in the same host;
and that Aphelinus, coming after Aphidius for a day, would
never hatch. In fact, the egg would never begin development as
shown in the characteristic change in appearance (Plate I,
Fig. 3, 4 and 5.)

Possible Ways hy Which Aphidius May Cause the Death of

Aphelinus.

Just how the death of Aphelinus is brought about still
remains a mystery that will only be solved by more careful
investigation. Several theories are suggested to explain it, but
all of them require refined methods to prove. They are given
here for what they are worth.

234 E. A. HARTLEY Vol. XXII, No. 8

Cannibalism. — Aphidius is much better armed with man-
dibles and a spiny body, than Aphelinus, and is also more
active. It might, therefore, be expected to kill Aphelinus by
feeding directly on it or injuring it fatally by striking against it
in the host. Yet, in the many cases that were examined, Aphid-
ius was never found feeding on Apheli?uis, nor did there ever
appear evidence of mutilation in the dead larvae. In each case,
Aphelinus simply stopped movement and turned darker in
color, in which condition it remained until it finally shriveled up
and disintegrated.

Starvation. — This theory does not carry much weight when
we consider the abundant supply of food present at the time
of death.

Toxic Substance. — It is quite possible that something of this
nature may be thrown off by Aphidius that has an injurious
effect on Aphelinus, but it is difficult to prove.

Lack of Oxygen. — Our knowledge of respiration in this
group of parasites is still very meager, so it is scarcely possible
to say just how the above condition might effect the parasites.
It appears that both derive their oxygen from the blood of the
host, in which they float, and it is also possible that Aphidius,
being the more active of the two and better adapted for breath-
ing might get around and monopolize it; though it is doubtful
if this could be reduced low enough to kill Aphelinus and not
work permanent injury on Aphidius.

Economic Importance.

While the above theories are of considerable importance
from a biological standpoint, it is sufficient for economic pur-
poses simply to know which of the two parasites will dominate
when the two come together. This the writer has shown. Since
Aphidius is the more efficient one in every respect, there need
be little fear over the fact that it will kill Aphelinus, since this
efficiency will in no way be lessened where they accidentally
come together. The aphids that Aphelinus parasitized would
not interfere with Aphidius, and would be so many more dead
aphids in addition to those killed by Aphidius.

June, 1922 bionomics of alpiielinus semiflavus 235

SECONDARY PARASITES.

Throughout most of the winter of 1921-22, at Columbus,
Ohio, very few secondary parasites appeared to infest Apheliniis
in the greenhouse insectary. But by February, two species
began to appear in from ten to twenty percent of the specimens
taken in the open greenhouse. One was determined by Mr.
Gahan of the United States National Museum, as Asa plies
{Megorismiis) a?nericana Gir., and the other by Mr. Rowher,
also of the Museum, as Alloxysta sp., a Figitid resembling
Charips (Allottria).

In the fall of 1921, another secondary was reared from a
new species of Apheliniis on a juniper aphid near Philadelphia,
Pennsylvania, which likewise proved to be a secondary of
Apheliniis semiflavus. This was determined by Mr. Gahan as
Aphidencyrtus aphidiphagits Ashm.

LITERATURE.

Agee, H. F., and Swezey, O. H.

1919. Director's Report to the Annual Meeting of Hawaiian Sugar Planters
Association. Dec. 2, 3 and 4, 1919, pp. 153.
Back, F. A. and Pemberton.

1916. Parasitism Among the Larvae of the Mediterranean Fruit Fly (Cera-
titis capitata). Jour. Econ. Entom. 9:306, 1916.
Gahan, A. B.

1911. Aphidininae of North America. Maryland Agric. Exp. Sta., Bull.
No. 152.

GiRAULT, A. A.

1909. A New Chalcidoid of the Eulophid Genus Aphelinus Delman. Parasitic

on Schizoneura crataegi Oestlund, Psyche. Vol. 16, pp. 29-31.
1911. A New Aphid-infesting Aphelinus which is not Black. Entomologist,

Vol. 44, pp. 178-179.
1916. Description of and Observation on some Chalcidoid Hymenoptera.

Canadian Entom. xlviii. No. 7, July, 1916. pp. 242-246.
Howard, L. O.

1907. New Genera and Species of Aphelininae, with a Revised Table of

Genera. U. S. D. A., Div. Ent., Tech. Ser. 12, pp. 69-88.

1908. The Importation of Tetrastichus xanthomelaenae Rond. Jour. Econ.

Entom. Vol. I, No. 5, p. 281.
1908a. Upon the Aphis-Feeding Species of Aphelinus, Ent. News, Vol. 19, pp.
365-367.

1910. On the Habit with Certain Chalcidoidea of Feeding at Puncture Holes

Made by Ovipositor, Jour. Econ. Entom. Vol. 3, pp. 257-260.

1911. Existe-t-il un Changement dans la fauna des Aphelinidae en Europe?

Bull. Soc. Ent. France, 1911, pp. 258-259.
1911. A New Aphis-Feeding Aphelinus. Proc. Biol. Soc. Wash. D. C. Vol. 25,
Mar. 31, pp. 77-78.

236 E. A. HARTLEY Vol. XXII, No. 8

KURDJUMOV, N. V.

1913. Notes on European Species of the Genus Aphelinus Dalm. Parasitic
upon Plant Lice. Revue Russe d' EntomologiCj Vol. XIII, No. 2,
Oct. 20, 1913, pp. 266-270.
Marchal, Paul.

1909. La Ponte des Aphelinus et I'interet individual dans les actes lies a la

conservation de 1' espece. C. R. Acad. Sc. t. 148, pp. 1223-1225.

QUAYLE, H. J.

1910. Aphelinus Diaspisis How. Jour. Econ. Ent. Vol. 3, p. 398.
ROCKWOOD, L. P.

1917. An Aphis Parasite Feeding at Puncture Holes made by Ovipositor.
Jour. Econ. Ent. Vol. 10, 1917, No. 4, p. 415.
Shull, a. Franklin.

1910. Do Parthenogenetic eggs of Hymenoptera Produce only Males? Amer-
ican Nat. Vol. XLIV, No. 518.
Smith, H. S.

1916. An attempt to Redefine the Host Relationships Exhibited by Ento-
mophagous Insects. Jour. Econ. Ent. Vol. 9, No. 5, p. 477.
Smith, H. S., and Compere, Harold.

1920. The Life-History and Successful Introduction into California of the
Black Scale Parasite, Aphycus lounsburyi How, Monthly Bull. Dept.
Agric. State of Cal. Vol. 9, No. 8.
Webster, F. M., and Phillips, W. J.

1912. The Spring Grain Aphis or "Green Bug." U. S. D. A. Bur. Ent. Bull.
110.

EXPLANATION OF PLATE.

Fig. 1. Adult female Aphelinus semiflavus with male antenna and genitalia in

insert.
Fig. 2. Female Aphelinus ovipositing in aphid nymph.
Fig. 3. Egg less than five hours old.
Fig. 4. Egg twenty-four to twenty-eight hours old.
Fig. 5. Egg forty-six to forty-eight hours old.
Fig. 6. Small larva just hatched.

Fig. 7. Lateral view of full grown larva, just before pupation.
Fig. 8. Front view of larval head, greatly enlarged.

All figures, except Figure 8, are drawn approximately to the same scale,
enlarged thirty-three and a third times.

Bionomics of Alphelinus Semiflavus
E. A. Hartley

Plate I.

.r^

E. A. Hartley.

INDEX TO VOLUME XXII.

Academy of Science, Ohio 1

A Case of Unhindered Growth of
the Incisor Teeth of the Wood-
chuck 170

Additions to Ohio Vascular Plants
for 1921 91

Alaskan Diptera of the Family
Syrphidae 143

Alphelinus Semiflavus, Some Bio-
nomics of 209

An Annotated List of Mississippi
Chrysomelidae 117

A New Hymenopterous Parasite
Upon Adult Beetles 140

A New Species of Plea 114

A New Type of Bryozoan Gizzard
with Remarks on Genus Beeskia 158

Arisaema, Sexual Nature of Twins 149

A Synopsis of the Genus Steno-
cranus 69

Binomics of Alphelinus Semi-
flavus 209

Bryozoan Gizzard, New Type of 158
Beeskia, Remarks on Genus 158

Catalog of Ohio Vascular Plants

for 1921 91

Chrysomelidae, List of Mississippi 117
Classification of Plants, XII. ... 129
Common Misconceptions of Evo-
lution 173

Common Mole, Habits of 164

Concretions in Lake Deposits at

Elyria, Ohio 97

Cottus Ictalops, Food Habits. ... 95

Darters, Food of Ohio 41

Descriptions of Alaskan Diptera

of the Family Syrphids 143

Dichotomous Twins of Arisaema 149
Diptera of the Family Syrphidae. . 143

Dodder Gall Weevil 63

Dynamics of the Lithosphere. . . . 193

Emergence of a Mayfly from its
Nymphal Skin 155

Evolution, Sexual, in the Plant
Kingdom 101

Evolution, Some Common Mis-
conceptions of 173

Food Habits of Young of Cottus
Ictalops 95

Food of the Common Ohio
Darters 41

Glacial Material, Rock Channels
Filled With 125

Growth of the Incisor Teeth of
Woodchuck 170

Habits of the Common Mole 164

Homologies of the Tracheal

Branches of Insects 84

Hymenopterous Parasites upon

Adult Beetles 140

Incisor Teeth of the Wood-
chuck, Growth of 170

Insects, Respiratory System of . . 84

Lake Deposits, Concretions in. . . 97
Lithosphere, Dynamics of the. . . . 193

Mayfly, Emergence from

Nymphal Skin 155

Misconceptions of Evolution. . . . 173

Mississippi Chrysomelidae 117

Mole, Habits of Common 164

Mysidia, New Species of 69

New Hymenopterous Parasite

upon Adult Beetles 40

New Species of Mysidia 69

New Type of Bryozoan Gizzard. . 158
Notes on the Food Habits of
Young of Cottus Ictalops 95

Ohio Academy of Science, Report 1

Ohio Darters, Food of 41

Ohio Vascular Plants for 1921 .... 91

Plants, Classification of 129

Plea, a New wSpecies of 114

Preservation of Natural Con-
ditions 99

Progression of Sexual Evolution
in the Plant Kingdom 101

Report of Thirty-first Meeting,

Ohio Academy 1

Respiratory System of Insects. . 84
Rock Channels and Cavities
Filled With Glacial Material. . 125

Sexual Evolution in the Plant
Kingdom 101

Sexual Nature of Vegetative or
Dichotomous Twins of Arisaema 149

Smicronyx SculpticoUis, Notes on 63

Some Bionomics of Alphelinus
Semiflavus 209

238

INDEX TO VOLUME XXII

239

Some Common Misconceptions of
Evolution 173

Some Sub-Surface Rock Channels
and Cavities Filled with Glacial
Material 125

Stenocranus, Synopsis of Genus. . 69

Sub-Surface Rock Channels and
Cavities Filled With Glacial
Material 125

Syrphidae, Descriptions of Alaskan 143

The Classification of Plants. XII 129
The Homologies of the Tracheal
Branches in the Respiratory
System of Insects 84

The Sexual Nature of Vegetative
or Dichotomous Twins of
Arisaema 149

Thunderstorms; Especially those
of Ohio 21

Tracheal Branches in Insects. .. . 84

Twins of Arisaema, Sexual

Nature of 149

Vegetative or Dichotomous Twins
of Arisaema 149

Woodchuck. Growth of Incisor
Teeth 170