218 A. £J. •Verrill — Revision Genera and Species of Starfishes. 



One specimen of this species (No. 15,570) is remarkable for having, 

 on one of the interraclial margins, a pair of plates in place of the 

 usual odd median plate. 



Figure 7, plate xxx, represents the abnormal segment of this spe- 

 cimen, with the jaw and corresponding pair of marginal plates 

 [m, m), and figure 7a represents a normal segment and jaw of the 

 same specimen, with the odd marginal plate (m). 



Family ASTROPECTINIDiE Gray. 



Blakiaster conicus Perrier. 



Blakiaster conicus Per., 1881, p. 28. Etoiles de Mer, p. 365, pi. ix, fig. 2, 



1884. 

 Leptoptychaster conicus Per., Exp. Trav. et Talism., pp. 242, 243, 1894. 



Plate XXVIl. Figure 7. 



Perrier, in his later report, has united this genus with Leptopty- 

 chaster, but it seems to me sufficiently distinct, though doubtless 

 they are closely allied. In this genus the actinal plates are not 

 arranged in distinct radial series, nor do they have such well devel- 

 oped fascioles between them. On the contrary, they have a rather 

 irregular, crowded, tesselated arrangement, the plates being round- 

 ish or polygonal, pretty closely united, without deep, sutural, fas- 

 ciolated furrows. The marginal plates, also, have only rudimentary 

 fascioles. The jaws are stout and evenly convex, instead of thin 

 and carinate. The dorsal paxillre are larger, rounded, and more 

 regular. 



There is a distinct dorsal nephridial pore or "anus." The dorsal 

 papulae are large, five or six around each plate, except on the distal 

 half of the ray and on the small interradial areas. 



The lower marginal plates have three or four larger and longer 

 spines on the border. 



There are also, on some of our specimens from off Havana, a 

 number of pedicellariai. Those on the actinal and adambulacral 

 plates have four to six convergent papilliform blades, similar to the 

 surrounding spinules, but rather stouter and blunter (see \\. xxvii, 

 fig. 7). Similar ones, but smaller, with three or four blades, occur 

 on the marginal and abactinal plates. 



West Indies and Gulf of Mexico, 92 to 175 fathoms. 



