ILLINOIS GEOLOGtCAl 



SURVEY tmQAPV 



O 



/Oh ZtJ 



STATE OF ILLINOIS 



DEPARTMENT OF REGISTRATION AND EDUCATION 



Chronology and Molluscan Paleontology 

 of Two Post-Woodfordian Bogs 

 in Northeastern Illinois 



A. Byron Leonard 



ILLINOIS STATE GEOLOGICAL SURVEY 



John C. Frye, Chief Urbana, IL 61801 



CIRCULAR 487 1974 



