Page 

 Present State of Nematocyst Research: Types, Struc- 

 ture, AND Function ........ 187 



Cadet Hand 



Activation of the Feeding Reflex in Hydra Uftoralis . 203 



Howard M. Lenhoff 



The Nutrition of Hydra ...... 233 



David L. Claybrook 



Isolation and Maintenance in Tissue Culture of Coe- 



LENTERATE CeLL LiNES ....... 245 



John H. Phillips 



Symbiosis in Marine and Fresh Water Coelenterates . 255 



Leonard Muscatine 



On the Relation of Calcification to Primary Produc- 

 tivity IN Reef Building Organisms ..... 269 



T. F. Goreau 



The Development of Cordylophora .... 287 



Chandler Fulton 



Developmental Problems in Campanidoria . . . 297 



Sears Crowell 



Patterns of Budding in the Freshwater Hydroid Cras- 

 pcdacusta .......... 317 



Charles F. Lytle 



