STATE OF ILLINOIS 
DwicuT H. GREEN, Governor 
DEPARTMENT OF REGISTRATION AND EDUCATION 
FRANK G. THOMPSON, Director 
Nem eerie Hal 5 IOs R>yp 5 OU RVoh ye ba VES LON 
‘THEODORE H. FRison, Chief 
Illinois Natural History Survey 
BULLETIN 
V olume 22 
Ab 
Zr IA 
THE LIBRARY OF THE 
CCT 8 1945 
UNIVERSITY OF ILLINOIS 
Printed by Authority of the State of Illinois 
UBRER AON A Eel N OU. 
1941-1943 
