GUIDEBOOK SERIES 10 

 linois State Geological Survey 



PENNSYLVANIAN CONODONT 

 ASSEMBLAGES 



from 



LA SALLE COUNTY, NORTHERN ILLINOIS 



CHARLES COLLINSON 

 MATTHEW J. AVCIN 



Illinois State Geological Survey 



RODNEY D. NORBY 



University of Illinois 



GLEN K. MERRILL 



University of Texas, Arlington 



prepared for annual meeting 



PANDER SOCIETY 



in cooperation with North-Central Section 



THE GEOLOGICAL SOCIETY OF AMERICA 



DeKalb, Illinois 

 May 11-14, 1972 



