VERTEBRATE 

 ZOOLOGY 



AN INTRODUCTION TO THE COMPARATIVE 



ANATOMY, EMBRYOLOGY, AND EVOLUTION 



OF CHORDATE ANIMALS 



BY 



G. R. de BEER, M.A., B.Sc, F.L.S. 



FELLOW OF MERTON COLLEGE, JOHN WILFRED JENKINSON MEMORIAL 



LECTURER IN COMPARATIVE AND EXPERIMENTAL EMBRYOLOGY 



IN THE UNIVERSITY OF OXFORD 



WITH AN INTRODUCTION BY 



JULIAN S. HUXLEY, M.A. 



ULLERIAN PROFESSOR OF PHYSIOLOGY ROYAL INSTITUTION 



NEW YORK 



THE MACMILLAN COMPANY 



1928 



