KEY TO THE FAMILIES OF NORTH 

 AMERICAN INSECTS 



AN INTRODUCTION TO THE CLASSIFICATION 

 OF INSECTS 



BY 



CHARLES T. BRUES 



Assistant Professor of Economic Entomology 

 Harvard University 



AND 



A. L. MELANDER 



Professor of Entomology, State College 

 of Washington 



BOSTON, MASS., AND PULLMAN, WASH. 



Published by the Authors 



1915 



