CONTENTS. 



PAGE. 



Introduction 163 



Material antl methods 166 



Serial description of embryos 168 



Development and reduction of the tail 182 



Chorda dorsalis 188 



Development of the caudal end of spinal cord. . . 189 



162 



PAGE. 



Abnormahties of caudal end of spinal cord .... 193 



Spinal ganglia 193 



Sympathetic ganglia 193 



Summary ' 194 



Bibliography 196 



Description of plates 197 



