AMERICAN SCIENCE SERIES 



ZOOLOGY 



FOR 



HIGH SCHOOLS AND COLLEGES 



BY 



A. S. PACKARD, JR., M.D., PH.D. 



MEMBER OP THE NATIONAL ACADEMY OF SCIENCES ; PROFESSOR OF ZOOLOGY 

 AND GEOLOGY IN BROWN UNIVERSITY. 



SECOND EDITION, REVISED 



NEW YORK 

 HENRY HOLT AND COMPANY 



1880 



