AN INTRODUCTION TO THE 

 STUDY OF THE : 



COMPARATIVE ANATOMY 

 OF ANIMALS 



X 



BY 



GILBERT C. BOURNE, M.A., D.Sc., F.R.S., F.L.S., F.Z.S. 



F'ellmt> of Merton College and Linacre Professor of Comparative 

 Anatomy in the University of Oxford 



VOL. II. 



THE CCELOMATE METAZOA 



NINTH EDITION, REVISED 



LONDON 



G. BELL AND SONS, LTD. 

 1919 



