INTRODUCTION 



I 



1902. Part X. " The Origin of the Auditory Organ : the Meaning- of the 



Vlllth Cranial Nerve," vol. xxxvi., p. 164. 



1903. ., XI. '" The Origin of the Vertebrate Body-cavity and Excretory 



Organs : the Meaning of the Somites of the Trunk and 

 of the Ductless Glands," vol. xxxvii., p. 168. 



1905. .. XII. " The Principles of Embryology," vol. xxxix., p. 371. 



1906. .. XIII. " The Origin of the Notochord and Alimentary Canal," 



vol. xl., p. 305. 



