CCELENTEEATA : HTDEOZOA. 75 



In whichever of these forms the gonophore may be present, 

 the place of its origin from the trophosome may vary in 

 different species of the order. 1. They may arise from the 

 sides of the polypites, as in Coryne and Stauridia. 2. They 

 may be produced from the ccenosarc, as in Cordylophora. 

 3. They may be produced upon certain special processes, which 

 are termed 'gonoblastidia,' as in Hydractinia and Dicoryne. 

 These gonoblastidia are processes from the body-wall or 

 ccenosarc, which closely resemble true polypites in form, but 

 differ from them in being usually devoid of a mouth, and in 

 having shorter tentacles. 



As regards the development of the Corynida, the embryo 

 is very generally, though not always, ciliated at first, and 

 becomes developed into a hydra-form polypite, which fixes 

 itself to some foreign, body, and then (if not belonging to one 

 of the simple forms) proceeds to produce by gemmation the 

 composite adult. The development of the Corynida (as well 

 as that of the Sertularida and Lucernarida) obeys the general 

 law that the new polypites are developed at, or near, the 

 distal end of the hydrosoma ; so that the distal polypites are 

 the youngest, the reverse of this obtaining amongst the 

 oceanic Hydrozoa. 



Fig. 15. Corynida. Fragment of Eudendrium rameum, enlarged. 



The subject of the reproduction of the Corynida having 

 been treated at some length, so as to apply to the remaining 

 Hydroi-da, we shall now give a brief description of the two 

 leading types of structure exhibited by the order. 



Eudendrium, a genus of the Corynida, which is not un- 

 commonly found attached to submarine objects, usually in 



