STUDIES IN THE DEVELOPMENT OF SCYPHOMEDUSiE 



CHAS. W. AND G. T. HARGITT 



From the Zoological Laboratory, Syracuse University 



With Forty-nine Figures 



CONTENTS 



Introduction 217 



Material and Methods 218 



General Account 219 



Breeding Habits 220 



Historical 224 



Cyanea arctica 231 



Cleavage 232 



Gastrulation 234 



Aurelia flavidula 237 



Oogenesis 237 



Maturation 238 



Cleavage 241 



The Germ Layers 242 



Later Development 245 



The Planula 245 



The Scyphistoma 246 



The Ephyra 249 



Bibliography 252 



Introduction 



Several years ago the senior author began a more or less de- 

 tailed study of the life history and development of Cyanea arctica, 

 devoting to the subject both laboratory research, and such atten- 

 tion to distribution and open sea habits as was afforded by a 

 cruise of several days to the Gulf Stream on the schooner Gram- 

 pus, of the Fisheries Bureau. 



