STATE OF ILLINOIS 

 DwiGHT H. Green, Governor 



DEPARTMENT OF REGISTRATION AND EDUCATION 

 Frank G. Thompson, Director 



NATURAL HISTORY SURVEY DIVISION 

 Theodore H. Frison, Chief 



Volume 23 BULLETIN Article 1 



The Caddis Flies, or 

 Trichoptera, of Illinois 



HERBERT H. ROSS 



Printed by Authority of the State of Illinois 



URBAN A, ILLINOIS 



August 1944 



