138 



PTYCHOGENA LACTEA. 



pouches as there are pomts to the projections of the chymiferous 

 tubes ; the folds become smaller and smaller (Fig. 222) towards the 

 abactinal pole, and are connected by a loose fold with the actinostome. 

 The opening of the actinostome is large ; its folds are small, and do 



Fig. 221. 



Fi<r. 220. 



not form regular lips, but merely an irregular quadrangular frill. (Fig. 

 223.) The tentacles are extremely numerous, opening into a large circu- 

 lar tube ; they are very much flattened in one direction (/, Fig. 224) ; 

 between every two tentacles is found a club-shaped appendage, made 



Fig. 223. 



Fip. 224. 



up of large cells somewhat Uke those of Laf<x,a calcarata (h, Fig. 224) ; 

 the tentacles are capable of great expansion, and when contracted are 

 usually curled up tightly, as is the case in Melicertum and Staurophora ; 

 they are very frequently tied up in festoons, as in Fig. 220. This 



Fig. 220. Profile view of Ptychogena, somewhat reduced. 



Fig. 221. Magnified \-iew of the genital organs, seen from the abactinal pole. 



Fig. 222. The same as Fig. 221, seen in profile, on a somewhat smaller scale. 



Fig. 223. Actinostome. a, opening of actinostome ; p, point of attachment of the digestive 

 cavity ; I, lips of the actinostome. 



Fig. 224. Magnified base of tentacles and club-shaped appendages. /, swelling of tentacles ; 

 h, club-shaped appendages. 



