300 BULLETIN 100, UNITED STATES NATIONAL MUSEUM. 



middle of R, or to the fifteenth (or sixteenth) inferomarginal, the 

 plates having upward of 6 small pedicellariae each, with a few 

 scattered over the rest of the area, and the marginal granules are 

 similar to those of the marginal plates. 



Adambulacral plates with an angular furrow face deep in fur- 

 row, the margin varying from a slightly convex contour to a slight 

 compound curve, or a shallow angle near the adoral end or anywhere 

 between the adoral end and middle. On the outer part of the ray 

 the plates are evenly convex on the margin, the convexity of oppo- 

 site plates meeting in the middle of ray and separating consecutive 

 pairs of tube feet. Furrow comb consisting of proximally 6 to 8, 

 farther along ray 9 to 11, short, blunt, granuliform, subequal spine- 

 iets, the mesial more or less compressed with edge to furrow, the 

 lateralmost somewhat thicker and prismatic or flattened with side 

 to furrow. On the outer fourth of ray the furrow spinelets are 

 again reduced to 6 to 8 and at the tip to 4 or 5. Border of plate 

 with a row of unequal subconical immersed granules, and surface 

 ■with several, usually forming a longitudinal series spaced from 

 furrow comb. One to 3 small pedicellariae usually present, often 

 taking the place of several granules, being surrounded by a smooth 

 area. They are slightly larger than actinal intermediate pedicel- 

 lariae and have 2 or 3 similar jaws. Far along the ray the aboral 

 granule or spinelet of the furrow series is considerably enlarged 

 over the others. This gradually becomes the tubercular spine 

 (though very small) characteristic of the distal plates of many 

 genera of Goniasteridae. It functions as a sort of operculum to 

 protect the tube feet. 



Mouth plates small, rather evenly triangular, the straight furrow 

 margin with 7 to 9 furrow spines, the 2 inner enlarged, heavy, com- 

 pressed, prismatic, sometimes unequal, either round-tipped or bluntly 

 pointed. Suboral granules 20 to 25 immersed, close-set, the row ad- 

 jacent to furrow slightly the heaviest. 



Madreporic body hexagonal, surrounded by 6 plates, with coarse 

 irregular ridges radiating from center. In the cotype the striae are 

 fine, very meandering, and interrupted, but in the type are fairly 

 straight. 



Anatomical notes. — Gonads, a large cluster on either side of the 

 membranous interradial septum, the aperture about 10 mm. from 

 inner edge of marginal plates and 5 mm. from interradial septum. 

 Polian vesicles, 1 in each interradius. 



Type.—Q^i. No. 28658, U.S.N.M. 



Type-locality.— ^t^tion 5272, western Luzon, 25.5 miles southwest 

 Corregidor Light (lat. 14° N.; long. 12° 22' 30" E.), 118 fathoms, 

 mud, shells, coral sand, bottom temperature 57.4° F. 



Distribution. — Off western Luzon, 114 to 118 fathoms. 



