ACIINOZOA. 



229 



The important diversities of form in the polyp stocks are not 

 only occasioned by the differences of structure of the skeleton of the 



FIG. 175. Vertical section 

 through the cup of Cyathi- 

 na Cyathus (after Milne 

 Edwards). 8, Septa ; P, 

 pali ; C, columella. 



polyp, but are also the 

 resultant of varying 

 methods of growth by 

 gemmation and imper- 



FIG. 17-1. -Vertical section through a polyp <if Axfrniiles 

 enlycuUiris (after Lacaze Duthiers). The mouth open- 

 ing and tesophageal tube are seen as well as the me- 

 senteries fastened to the same ; also the calcareous 

 septa between the mesenteries, and the columella of 

 the skeleton, Sk. 



feet fission. According 

 to the method, nume- 

 rous modifications of 

 branched stocks are dis- 

 tinguished, e.y., Madre- 

 pores (fig. 176), Ocitll- 

 nidce (fig. 177), and the 

 lamellar and massive 

 stocks as Astiwa (fig. 

 178) and the Jfcean- 

 drinidfK (fig. 179). 



The Anthozoa are all 

 inhabitants of the sea, 

 and live mostly in the warmer zones, but certain types of the fleshy 



FIG. 170. adi-i'/iuni rernt- 

 cosa after Ed. H. 



FIG. 177. Branch of Ocit- 

 tina speeiotsa (after Ed. 

 H). 



