624 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.43. 



or 8; subambulacral spines, 6 to 10, 1 being enlarged; usually 1 or 2 

 subambulacral pedicellarise; first adambulacral plate compressed; 

 marginal mouth spines much compressed. 



Type.— Cat. No. 30532, U.S.N.M. 



Type-locality. — Station 5606, Gulf of Tomini, Celebes, 834 fathoms, 

 green mud. 



Tliis species is remarkable for the typical paxillse and well developed 

 marginal fascicles. It is not closely related to any described species. 

 Among the forms dredged by the Challenge?^ it shows most resem- 

 blance to D. spinosus, but has perpendicular sides to the ray, taller, 

 more penicillate paxillas, and characteristic pedicellarise. These on 

 the abactinal surface, resemble rather large globular granules split 

 nicely into 3 to 5 sections. 



The adambulacral plates are narrow, being much longer than wide, 

 with a rounded furrow margin bearing 7 or 8 fairly long, bluntly 

 pointed, compressed spines, -wddened and blade-like at the base, and 

 sometimes rather abruptly constricted near the tip, the median spines 

 being slightly the longest and all forming a vertical comb. Close to 

 these on the surface of the plate is an irregular longitudinal series of 

 6 to 10 cylindrical, pointed spines of wliich one near the center is 

 enlarged and subequal to or longer than the furrow spines. But on 

 the outer part of the ray the other spines are abruptly smaller, one- 

 half to two-thirds the length of the larger, and not clearly arranged in a 

 series. Most of the plates bear 1 or 2 prominent pedicellariae, with 

 usually 3 jaws, shghtly longer than those of the actinal interradial 

 areas. The latter resemble, in miniature, flower buds with 4 to 8 

 fleshy petals, and are found on a majority of the actinal intermediate 

 plates. 



A large abactinal paxilla has 15 to 20 spinelets of wliich 3 to 5 stand 

 on the convex top of the pedicel and the others, %vith a slight basal 

 web, form a peripheral series. The paxillse resemble, on a small 

 scale, those of Solaster papposus. 



Family GONIASTERID^. 



MIMASTER NOTABILIS, new species. 



Differing from M. tizardi in having much slenderer rays, more 

 numerous paxillar spinelets, more prominent paxilliform marginal 

 plates, a narrower actinal intermediate area on ray, and fewer 

 adambulacral spinelets. R=104 mm., r = 35 mm., R = 3 r; breadth 

 of ray at base, 39 mm. Paxillge slightly spaced, with upward of 75 

 deUcate, terete, pointed spinelets, either closely appressed in a 

 cylindrical upright group, or radiating and forming a subglobose 

 crown; marginal plates small, paxilliform, the inferomarginals the 

 larger, about as high as the length of the base, and standing out 

 horizontally from ambitus, the crown of spinelets compressed a^nd 



