206 PROCEEDINGS OP THE AMERICAN ACADEMY 



Pourtalesia rosea, A. Ag., nov. sp. 



Fragments only of this species were collected. It is, however, well 

 characterized by the peculiar shape of the anal snout, which is later- 

 ally compressed, truncated posteriorly. From the few fragments of 

 the test found they must belong to a large species closely allied to P. 

 ceratopyga. — Station 272, 2,600 fathoms. 



Cionobrissus revinctus, A. Ag., nov. gen. & sp. 



This genus is interesting, pointing as it does to the affinity of the 

 Pourtalesise and Brissina. It resembles Brissopsis somewhat, has 

 like it a peripetalous fasciole and petaloid ambulacra, and also pos- 

 sesses a well-marked subanal fasciole surrounding what corresponds to 

 a rudimentary anal snout, somewhat like the beak of Echinocardium. 

 The large tubercles within the peripetalous fasciole recall Macro- 

 pneustes, and the groove at the end of which is placed the actinos- 

 tome, with the rounded actinal surface with its keeled actinal plastron, 

 remind us somewhat of the Pourtalesiae. The spines of the test are 

 pretty uniform in size, with the exception of the larger ones within 

 the peripetalous fascioles. — Station 191, 800 fathoms. 



Echinocrepis cuneata, A. Ag., nov. gen. & sp. 



This genus has, like Pourtalesia, a deeply-sunken actinal groove 

 and simple ambulacral pores piercing the test. It has, like the species 

 of the group to which P. ceratopyga belongs, a triangular outline when 

 seen from above, with re-entering base and sides and somewhat angu- 

 lar rounded corners, but has no anal snout ; anal system placed on the 

 actinal side. Seen in profile, the apex is anterior, corresponding with 

 the abactinal system. The test is uniformly covered with small tuber- 

 cles carrying small slender spines, with the exception of a few larger 

 tubercles near the abactinal area in the interambulacral spaces, along 

 the actinal keel and the anterior interambulacral spaces of the actinal 

 side, and round the anal system. Seen endwise, the outline is that of 

 a truncated cone. The color of the test is violet brown. — Station 

 147, 1,600 fathoms. 



Spatagocystis Challengeri, A. Ag., nov. gen. & sp. 



The new genera Spatagocystis, Cystechinus, Urechinus, and Geni- 

 copatagus are among the most interesting Ecbini ever discovered, on 

 account of their decided affinities to the strange group of Pourtalesiae, 



