ASTEEOIDEA OP H.M.S, ' CHALLE3S"GEE ' EXPEDITION. 225 



along tlie free portion of the ray indeterminable. Actinal mem- 

 brane with numerous fine muscular fibres. 



Unfortunately this delicate specimen has been so shattered 

 and distorted that its present state of preservation will not admit 

 of a satisfactory description. This difficulty of study is the more 

 to be regretted as the form is one of the deepest-dwelling Asterids 

 obtained during the Expedition. The characters above enumerated 

 are sufficient, however, to indicate that the species under notice 

 is clearly distinct from any other in the group. The attenuation 

 of the rays, the number and delicacy of the paxillse-spinelets, and 

 the characters of the actinal surface readily distinguish the form. 

 On these grounds I have deemed it advisable to establish the 

 species, although loth to do so on such imperfect material. 



Station 244. Lat. 35° 22' N., long. 169° 53' E. Depth 2900 

 fms. ; bottom temperature 1°"2 C; red clay. 



HtMENASTEE C-aELATFS, n. sp. 



Marginal contour stellato-pentagonoid ; interradial angles sharply 

 indented, the lesser radius being in the proportion of 63-3 per cent. ; 

 Ii=BO millim., r=19 millim. The dorsal area is concave, the 

 radii being curved upward and their extremities recurved and 

 quite turned over ; actinal area very convex. The radial areaa 

 are well marked out, the lateral margins converging gradually to 

 the tip, which is not attenuated or produced. A secondary mem- 

 brane extending beyond the actino-lateral spines forms a conspi- 

 cuous fleshy fringe. 



Supradorsal membrane rather thick. Paxillse with 4 to 5 

 spinelets, forming regular crowns, whicb elevate the membrane 

 into rhomboid or pentagonal areas, raised in relief as it were, and 

 closely placed, the margins of the tabulae being more or less in- 

 curved, and the interspaces between deep and furrow-like. 

 Muscular fibres closely interwoven, bands ill-defined, and meshes 

 irregular ; spiracula small, and frequently two or more together — 

 tbis structure being uniform over elevated areas and interspaces 

 alike. Tips of the paxillae-spinelets ouly slightly protuberant ; 

 the relief-areas w^hicb fall iu the margin of the ray are smaller, 

 more compressed, and somewhat modified in form from the others. 

 About 7 longitudinal rows of elevated areas or tabulce may be 

 counted at the base of a ray. 



Oscular orifice small, circumference at the base of the valves 

 pentagonal, 9-25 millim. iu diameter, and marked out by spiaeleta. 



