30 



HYDROZOA 



Fig. 5. 



ew 



Morphology of Cordylophora : — a, hydrosoma of Cordylo- 

 phora lacustris, growing on a dead valve of the swan-mussel ; 0, 

 longitudinal section of a portion of its ccenosare, with a singr 

 polypite ; c, another fragment of the same ccenosare, to whicA 

 are attached, a polypite, and three reproductive bodies, or gone* 

 phores, in various stages of development, the largest and m° s 



- o, mouth ; 8', cavity behind the 

 mouth ; 5, gastric cavity ; /c', interior of the ccenosare ; cp, end0 ' 

 derm ; /x, muscular layer; €*c, ectoderm; e/c', outer hard lay e ' 

 or polypary, excreted by ectoderm ; e/c", processes of ectoderiDf 

 connecting it with the inner surface of this hard layer. (AH e 

 cept a f magnified.) 



advanced containing ova ; 











