STATE ORFILVELINOGIS 
Witiiam G. STRATTON, Governor 
DEPARTMENT OF REGISTRATION AND EDUCATION 
VERA M. Brinks, Director 
BOARD OF NATURAL RESOURCES AND CONSERVATION 
VERA M. BINKs, Chairman 
A. E. Emerson, Ph.D., Biology 
L. H. Tirrany, Ph.D., Forestry 
Rosert H. ANDERSON, B.S.C.E., Engineering _ ‘ Sur 
Lioyp Morey, B.A., B.Mus., C.P.A., LL.D., President of the University of Illinois 
DELYTE W. Morris, Ph.D., President of Southern Illinois University 
NATURAL HISTORY SURVEY DIVISION 
Urbana, Illinois 
SCIENTIFIC AND TECHNICAL STAFF 
HARLOW B. MILLS, Ph.D., Chief 
Bessie B. East, M.S., Assistant to the Chief 
Section of Economic Entomology 
GeorGe C. Decker, Ph.D., Entomologist and 
Head 
J. H. Biccer, M.S., Entomologist 
L. L. ENGuiisu, Ph.D., Entomologist 
S. C. CHANDLER, B.S., Associate Entomologist 
Wituts N. Bruce, Ph.D., Associate Entomologist 
NorMan C. GANNON, Ph.D., Associate Ento- 
mologist 
Joun M. WriGut, Ph.D., Associate Entomologist 
Paut SurRANYI, Ph.D., Assistant Entomologist 
W. H. Luckmann, M.S., Assistant Entomologist 
Ronatp H. Meyer, B.S., Assistant Entomologist 
Joun W. Matteson, B.A., Field Assistant 
ROBERT SNETSINGER, M.S., Field Assistant 
Sue E. Watkins, Technical Assistant 
H. B. Petty, M.A., Extension Specialist in En- 
tomology* 
STEVENSON Moore, III, Ph.D., Extension 
Specialist in Entomology* 
Mouan Rao, M.S., Research Assistant* 
CLARENCE E. Wuite, B.S., Research Assistant* 
LouISE ZINGRONE, B.S., Research Assistant* 
Section of Faunistic Surveys and Insect 
Identification 
H. H. Ross, Ph.D., Systematic Entomologist and 
Head 
Mitton W. SANDERSON, Ph.D., Associate Tax- 
onomist 
Lewis J. STANNARD, JR., Ph.D., Assistant Tax- 
onomist 
Puitip W. Smitu, Ph.D., Assistant Taxonomist 
Leonora K. Gioyp, M.S., Laboratory Assistant 
VirGINiA A. WHIPPLE, Technical Assistant 
Section of Aquatic Biology 
GEORGE W. BENNETT, Ph.D., Aquatic Biologist 
and Head 
WituiaM C. Starrett, Ph.D., Associate Aquatic 
Biologist 
R. W. Larrmore, Ph.D., Associate Aquatic Bi- 
ologist 
Donatp F. HANSEN, Ph.D., Assistant Aquatic 
Biologist 
Rospert D. Crompton, Field Assistant 
LEONARD DurHAM, M.S., Research Assistant* 
P. L. McNet, B.S., Research Assistant* 
Wiirr1aM F. Cuivpers, B.S., Technical Assistant* 
ConsuLTANnts: HerpetoLocy, Hopart M. Situ, Ph.D., Associate Professor of Zoology, University of Illinois; 
PARASITOLOGY, NORMAN D. LEvINE, Ph.D., Professor of Veterinary Parasitology and of Veterinary Re- 
search, University of Illinois. 
_ *Employed on co-operative projects with one of several agencies: Tlinois Agricultural Extension Service, 
Illinois Department of Conservation, United States Army Surgeon General’s Office, United States Depart- 
ment of Agriculture, United States Fish and Wildlife Service, United States Public Health Service, and others. 
This paper is a contribution from the Section of Aquatic Biology. 
(1650—4,500—8-54) gan 2 
Section of Applied Botany and Plant 
Section of Game Research and Management 
Section of Publications and Public Relations 
Technical Library 
WALTER H. NEWHOUSE, Ph.D., Geology 
RoGEr ApaAMs, Ph.D., D.Sc., Chemistry 
Pathology 
J. Cepric CARTER, Ph.D., Plant Pathologist and 
Acling Head 
J. L. ForsBerc, Ph.D., Associate Plant Pa- 
thologist 
G. H. Boewe, M.S., Assistant Plant Pathologist 
R. J. Campana, Ph.D., Assistant Plant Pathol- 
ogist 
I. R. ScHNEIDER, PuH.D., Assistant Plant Pa- 
thologist 
E. B. Himetick, M.S., Assistant Plant Pathologist 
Rospert A. Evers, Ph.D., Assistant Botanist 
RoveniA F. Fitz-Geratp, B.A., Technical 
Assistant 
Harry J. KRrueEGeEr, B.S., Special Research 
Assistant* 
T. G. Scott, Ph.D., Game Specialist and Head 
Ravpu E. YEATTER, Ph.D., Game Specialist 
F. C. BELLROsE, B.S., Associate Game Specialist 
H. C. Hanson, M.S., Assistant Game Specialist 
J. S. JorpaNn, Ph.D., Assistant Game Technician 
Ross J. MILvLer, M.S., Field Ecologist 
FRANCES D. Ropsins, B.A., Technical Assistant 
WILLIAM NuEssS, Field Assistant 
LysLeE R. Pretscu, M.F., Project Leader* 
WiILtiAmM B. ROBERTSON, JR., M.S., Research 
Assistant* 
James OpsaH_, M.S., Field Assistant* 
Rosert H. Brouau, Field Assistant* 
JAMEs S. Ayars, B.S., Technical Editor and Head 
nies P. YounG, B.A., Assistant Technical 
itor 
WitiiaMm E. Crark, Assistant Technical Photog- 
rapher 
RosBert E. TEEGARDIN, Technical Assistant 
Rutu R. Warrick, B.S., B.S.L.S., Technical 
Librarian 
Ovca E. Grimincer, B.A., Assistant Technical 
Librarian 
