AMERICAN SCIENCE SERIES ADVANCED COURSE 



ZOOLOGY 



FOR 



HIGH SCHOOLS AND COLLEGES 



BY 



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



MEMBER OF THE NATIONAL ACADEMY OF SCIENCES; PROFESSOR OF ZOOLOGY 

 AND GEOLOGY IN BROWN UNIVERSITY 



EIGHTH EDITION, REVISED 



NEW YORK 

 HENRY HOLT AND COMPANY 



1893 



