VI INTRODUCTION 



Society's copy is mainly followed ; in the present volume 

 that of the Museum copy is quoted. 



Thanks are again due to the Council of the Zoological 

 Society, as well as to the Smithsonian Institute, Messrs. 

 Eowland Ward, and various friends, for cliches of published 

 figures or of photographs. 



May 10th, 1914. 



