/)^' 



STATE OF ILLINOIS 

 DEPARTMENT OF REGISTRATION AND EDUCATION 



NATURAL HISTORY SURVEY DIVISION 



STEPHEN A. FORBES. Chief 



Bulletin 



OF THE 



Illinois State Natural History 

 Survey 



URBANA, ILLINOIS, U. S. A. 

 VOLUME XVI 



1926-1927 



PRINTED BY THE AUTHORITY OF THE STATE OF ILLINOIS 



1927 



