210 PROCEEDINGS OF THE AMERICAN ACADEMY 



avnbulacral areas of the abactinal side are of very uniform size, those 

 of the bivium being, however, somewhat larger than those of the 

 trivium. Station 191, 800 fathoms. 



Paleopneustes Murrayi, A. Ag., nov. sp. 



A number of large reddish-brown specimens were collected, unfor- 

 tunately all nearly of the same size, so that I am unable to determine 

 if the presence of a more or less well defined lateral fasciole is a suffi- 

 cient reason for separating this species from the typical Paleopneustes, 

 in which this fasciole either does not exist, or only in a very rudimen- 

 tary condition. This species is at once separated from the West 

 Indian species by the lesser height of the test, the smaller actinal 

 plastron, the far greater length of the petaloid ambulacra, the propor- 

 tionally larger primary tubercles on the abactinal side of the test, and 

 the shorter truncated plane of the posterior extremity in which the 

 anal system is placed. — Station 232, 345 fathoms. 



Geulcopatagus affinis, A. Ag., nov. gen. & sp. 



This genus has striking affinities with Holaster, Toxaster, and Car- 

 diaster. The lateral ambulacra and the odd ambulacrum have an 

 identical structure, as in Toxaster, the ambulacra are slightly sunken, 

 the double pores giving the ambulacra above the ambitus a slight 

 petaloid appearance, much as in Paleopneustes. Seen in profile, the 

 test is hemispherical, with prominently labiate actinostome and a fiat 

 actinal surface. The primary tubercles occupy the central part of the 

 plates on the abactinal side of the test. On the actinal side the pri- 

 mary tubercles are large and prominent in the interambulacral areas. 

 The ambulacral plates carry but a few secondary tubercles. The 

 anal system is placed half-way between the ambitus and the abactinal 

 system. The color of the test varies from pinkish to yellowish green. — 

 Station 157, 1,950 fathoms. 



Hemiaster gibbosus, A. Ag., nov. sp. 



Seen in profile, the anal extremity is nearly vertically truncated, the 

 apex is close to the posterior edge, thence the test slopes gradually to 

 the anterior extremity, somewhat beyond the apical system, this is also 

 vertically truncated and rounded, the actinal line is quite flat. Seen 

 from above, the outline is elliptical, widest at posterior extremity. 

 Test covered with tubercles of uniform size and equally distributed 

 over the plates, except in the lateral posterior interambulacra, where 

 the plates are comparatively bare, as well as on the actinal surface, 



