1894. PROCEEDIKGS OF THE NATIONAL MUSEUM. 275 



of the ray are transversely obloiig, with a curved summit, aud bear 

 20 to 30 small slender spiimles mostly arranged in 2 rows; the up- 

 ])er ones are smallest and similar to those of the dorsal pseudopaxillae. 

 Beyond the middle of the ray the marginal plates become short and 

 bear an irregular group of crowded paxillary spinules. The upper mar- 

 ginal plates are small and bear paxilliform groups scarcely different 

 from those of the dorsal surface of the rays ; on most of the rays there 

 is an irregular row of small pseudopaxilhf just below the inferior mar- 

 ginal plates, but usually terminating before reaching the end of the 

 ray. 



Actinal interradial spaces narrow, elongated, and covered with a thick 

 skin which is radially striated and bears small scattered fascicles of 2 

 to 6 rather long, slender, paxillary spinules, while some similar spinules 

 stand singly, leaving much of the surface bare. The adambulacral 

 plates are crowded and each bears a furrow-group of 3 or 4 rather long, 

 tapering, acute spinules, which stand in a somewhat curved row, the 

 central one being larger and somewhat farther inward than the others; 

 outside of these, each plate bears a transverse row of about 10 to 12 

 closely i)laced spines, similar in size to the furrow- spines; some of these 

 spines are forked at the tip, others are obtuse, but most are acute, and 

 the outermost are somewhat smaller and more slender than the others. 

 In alcoholic specimens these spines, as well as all the furrow-spines, 

 are united by a web. The jaw-plates are narrow and elongated; each 

 bears 4 large, inwardly directed terminal spines, of which the 2 central 

 are decidedly larger and longer than the others, and also a row of 

 smaller acute spines on each side. The ventral surface of each jaw 

 forms a sharp, elongated carina inclosing a narrow elliptical space. 

 On each carina there are about 10 to 12 slender elongated spines. 



This species appears to be a true Crossaster, but differs widely from 

 C. papposus in the stouter and closer skeleton plates, smaller and more 

 numerous dorsal i^seudopaxilhi", with nuich shorter spinules, and in 

 the much more numerous and shorter adambulacral spines. 



It was taken in 1880 by the Gloucester fishermen, near George's 

 Bank, in deep water (schooner Martha C. Young.) 



Family P t e r a s t b k i d ^ , P e r r i e r . 

 PTERASTER (TEMNASTER) HEXACTIS, new species. 



Disk broad, very high, evenly convex, with a rather large central 

 opening surrounded by circles of prominent, imbricated, and webbed 

 spines. Rays six, short, broad, tapered to blunt tips, their lateral 

 margins convex. Lesser to greater radii, about as 1 to 1.5. Lesser 

 radii, 22 mm.; greater radii, 32 to 35 mm., in the alcoholic specimen; 

 height of disk, 30 mm. 



The surface of the disk is covered with very numerous small spin- 

 ules, covered more or less completely with a thick skin-like membrane 

 and arranged in irregular, divergent groui)s. 



