STATE OF ILLINOI S 



DwiGHT H. Green, Governor 



DEPARTMENT OF REGISTRATION AND EDUCATION 



Frank G. Thompson, Director 



BOARD OF NATURAL RESOURCES AND CONSERVATION 

 Frank G. Thompson, Chairman 



William Trelease, D.Sc, LL.D., Biology* Arthur Cutts Willard, D.Eng., LL.D., 



Ezra J. Kraus, Ph.D., D.Sc, Forestry President of the University of Illinois 



L. R. HowsoN, B.S.C.E., C.E., Engineering Norman L. Bowen, Ph.D., Geology 



Roger Adams, Ph.D., D.Sc, Chemistry 



NATURAL HISTORY SURVEY DIVISION 



Urbana, Illinois 



Scientific and Technical Staff 



Theodore H. Prison, Ph.D., Chief 



Florence A. Nyberg, Assistant to the Chief 



Section of Economic Entomology 



G. C. Decker, Ph.D., Entomologist 

 M. D. Farrar, Ph.D., Research Entomolo- 

 gist 

 J. H. Bigger, M.S., Associate Entomologist 

 S. C. Chandler, B.S., Southern Field Ento- 

 mologist 

 James W. Apple, M.S., Northern Field Ento- 

 mologist 



B. G. Berger, M.A., Assistant Entomologist 

 John M. Wright, B.A., Assistant Entomolo- 

 gist (on leave) 



H. B. Petty, Jr., M.A., Associate in Ento- 

 mology Extension 



C. J. Weinman, Ph.D., Special Research 

 Assistant 



Willis N. Bruce, B.S., Special Research 

 Assistant 



Section of Insect Survey 



H. H. Ross, Ph.D., Systematic Entomologist 

 Carl O. Mohr, Ph.D., Associate Entomolo- 

 gist, Artist (on leave) 

 B. D. Burks, Ph.D., Assistant Entomologist 



(on leave) 

 Milton W. Sanderson, Ph.D., Assistant 



Entomologist 

 Kathryn M. Sommerman, M.S., Artist, 



Entomological Assistant 

 Phyllis A. Beaver, Laboratory Assistant 



Section of Forestry 



James E. Davis, M.F., Extension Forester 

 Lee E. Yeager, Ph.D., Forester 



Section of Aquatic Biology 



George W. Bennett, Ph.D., Limnologist 

 D. F. Hansen, Ph.D., Assistant Zoologist 

 Paul G. Barnickol, M.A., Ichthyologist 

 Bruno von Limbach, M.S., Special Researd 

 Assistant 



Section of Game Research and Management 

 R. E. Yeatter, Ph.D., Game Specialist 



Section of Wildlife Experimental Areas 



Arthur S. Hawkins, M.S., Game Technicia, 

 (on leave) 



F. C. Bellrose, Jr., B.S., Assistant Game 

 Technician 



Harold C. Hanson, M.S., Assistant Game 

 Technician 



Section of Applied Botany and Plant 

 Pathology 



L. R. Tehon, Ph.D., Botanist 



J. C. Carter, Ph.D., Assistant Botanist 



G. H. Boewe, M.S., Field Botanist 



J. L. Forsberg, M.S., Research Pathologist 

 Bessie B. Henderson, M.S., Research 

 Assistant 



Section of Publications 



James S. Avars, B.S., Technical Editor 

 Eleanor G. Wolff, B.Ed., Assistant Tech 

 nical Editor 



Technical Library 



Marguerite Simmons, M.A., M.S., Tcchnica 

 Librarian 



Consultants in Herpetology: Howard K, Gloyd, Ph.D., Director of the Museum, Chicago 

 Academy of Sciences; Clifford H. Pope, B.S., Curator of Amphibians and Reptiles, Chicago 

 Natural History Museum. 



•Deceased January 1, 194S. 



This paper is a contribution from the Section of Aquatic Biology. 



(79323— 3M— 3-45) 



