SYNOPTIC KEY TO THE 

 PHYLA, CLASSES, AND 

 ORDERS OF ANIMALS 



WITH PARTICULAR REFERENCE TO FRESH-WATER 

 AND TERRESTRIAL FORMS OF THE MOIST 

 TEMPERATE REGION IN NORTH AMERICA 



Compiled by 



W. C. ALLEE 



Zoological Laboratory, University of Chicago 

 Based on a compilation originally made by 



V. E. SHELFO^RD 



The Vivarium, University of Illinois 



THE UNIVERSITY OF CHICAGO PRESS 

 CHICAGO - ILLINOIS 



