316 



ORGANS OF DIGESTION. 



FlG. 



with regular vertical series of dense white glistening calcare^- 

 ous spicula, attached to their parietes, and the internal 

 cavities of these polypi are continuous with the long tubular 

 radiating canals which traverse and almost constitute the 

 entire fleshy mass of the body. The internal structure is 

 very similar in pennatulce and viry.ularue, where the mature 

 free ciliated gemmules also pass out through the open cavity 

 of the stomach. In many zoophytes, each polypus forms a 

 separate animal, as in several tubularm^ caryophyllice, and 

 fungi where the cells are as isolated as the polypi. The 

 caryopfayllia cyathus is composed of an isolated calcareous 

 cell, containing a large polypus with a double row of conical 

 tubular tentacula destitute of cilia or any kind of lateral 

 appendices, and altogether constructed like an actinia in its 

 digestive sac and its vertical ovarial partitions. In the 

 winding superficial concavities of the meandrime is protected 

 the variously-coloured fleshy mass of the animal, with 

 numerous short conical polypi form orifices having generaUy 

 eight marginal lobes, the remnants of the eight fimbriated 

 short teotacula so common in the higher forms of zoophytes, 

 and along the margins of the prominent calcareous ridges 



