288 



CTENOPIIORiE. 



Pakt II. 



Fj 101 



Pandora the rows of locomotive flappers lie in a furrow, the margins of which 

 may close over them. They differ farther from Pandora in the more extensive 

 development of the rows of flappers, which reach near to the oral tube, and in 

 this respect they resemble more Idyia, with which they agree also in being much 

 compressed laterally. The circumscribed area is bounded by a fringe of deeply 

 lobed processes arranged in two prolonged circles, with the eye-speck between them, 

 in the centre. The eye-speck is not raised on a peduncle. The branching tubes 

 penetrating into the spherosome, Avhich Eschscholtz does not mention in Pandora, 

 are even more distinct than in Idj'ia ; and those arising from the circular oral 

 tuljc are quite numerous. The main chymiferous cavity, from which arise the 

 chyniiferous tubes, is a globular hollow, situated in the abactinal part of the sphero- 

 some and communicating with the wide digestive cavity through a narrow fissure. 

 The compression of the body is quite striking, and, upon contrasting a lateral and 

 a front view, these species appear rather flat. For this genus I would propose 

 the name of Idyopsis. 



Idyopsis Clarkii Aij. {Fig. 101). I inscribe this species to my friend Prof. H. 

 J. Clark, to whom I am indebted Fij. 102. 



for a sketch of its outlines, certain 

 that, when he has an opportunity 

 for examining it leisurely, he will 

 give us a most minute account of 

 its structure. From notes made 

 years ago, it appears that the rows 

 of locomotive flappers have on 

 each side a jjand of yellow and 



Ijrown stellate dots, and that the edge of the mouth, 

 "■ as Avell as the fringes around the circumscribed area, 

 were dotted in the same manner. The digestive cavity is occasionally constricted 

 about half way up its height, and may remain so for a long time, while the mouth 

 is broadly opened, and the constriction gliding toward the abactinal end of the 

 digestive cavity may reach the fissure leading into the main chymiferous cavity, and 

 disappear when the latter opens. Seen in profile from its broad side, this species 

 is nearly globular. Found in the harljor of Charleston. 



Idyopsis affinis Aff. differs from the preceding in being more flattened in front 

 and behind, and less rounded in its outUnes when seen from the broad side, the 

 actinal side being broader. Found along the reef of Florida, at Key West, and 

 about the Tortu^as. 



Idyopsis Claekii, Ay. 



Seen from the bro-id siJe. 



/ funnel. — I- T' anterior and posterior ambulacra. 



— I\ l^ lateral ambulacra. — d digestive cavity. 



— mouth surrounded by the oral tube, the 

 coeliac tube occupying the centre of the figure. 



iDYorsis Cl.\ekii, Ag. 



Seen from the abactinal side. 



c circumscribed area. —A ^s, HIo 

 lateral ambulacra. — /- l\ I'' H 

 anterior and posterior ambu- 



