MANUAL OF ZOOLOGY 



BY 



RICHARD HERTWIG 



PROFESSOR OF ZOOLOGY IN THE UNIVERSITY AT MUNICH 



THIRD AMERICAN 

 FROM THE NINTH GERMAN EDITION 



TRANSLATED AND EDITED BY 



J. S. KINGSLEY 



PROFESSOR OF ZOOLOGY IN TUFTS COLLEGE 



NEW YORK 



HENRY HOLT AND COMPANY 

 1912 



