276 BULLETIN 100, UNITED STATES NATIONAL MUSEUM. 



sis being about two-thirds the length of the aborai, which is slightly 

 hollowed out. The tube feet may be separated by the spines, as near 

 the mouth as the sixth or seventh plate,s, according to the width of 

 furrow^ and position of spines. On plates with a prominent angle 

 the median spines are the longest and slenderest, being compressed, 

 slightly tapering and blunt, while the lateral spines are shorter, 

 stouter, and blunter and have their broad side to furrow. Subambu- 

 lacral granules 16 to 25 in 3, sometimes 4, irregular rows; outer 

 granules hemispherical, becoming somewhat 4-sided or prismatic 

 toward the furrow, and in the disk the innermost series is enlarged 

 into short tubercular subprismatic spines, which decrease in length 

 as the base of ray is approached ; on the ray there are only granules. 

 On the disk a few plates have a small pedicellaria with 3 slender 

 curved jaws in the inner series of subambulacral spines opposite the 

 furrow angle. 



* Mouth plates with 11 or 12 furrow^ spines (as few as 10) and 2 

 series of about 15 suboral spines and granules. The furrow margin, at 

 the end of the plate, is hoUow^ed out for the first tube foot, so that the 

 marginal series of spines is not straight but in a compound curve. 

 Near the inner end of the combined plates the suborals form a double 

 series of 4 to 6 spines, each series diverging and running parallel to 

 the furrow margin, the outer half of plate being occupied by 

 granules. 



Madreporic body rather small, surrounded by 6 or 5 plates and 

 situated one-third the distance from center to inner edge of marginal 

 plates. 



Type.— Cat. No. 30546, TJ.S.N.M. 



Type-locality. — Station 5622, between Gillolo and Makyan Islands, 

 Molucca Islands, 275 fathoms, gray mud ; 1 specimen. 



Distribution. — Molucca Islands, 230 to 275 fathoms. 



Specimens examined. — The type and a specimen from station 5625 ; 

 betw^een Gillolo and Kayoa Islands, 230 fathoms gray mud, fine sand. 



Remarks. — This species differs from N. ludwigi (Koehler) in hav- 

 ing broader rays at the base which taper more abruptly; more 

 numerous marginals in each interbrachium ; wider adambulacrals 

 with 3 or 4 rows of granules instead of 2; much more prominent 

 apophyses proximally on the adambulacral plates; a few adambu- 

 lacral and actinal intermediate but no marginal nor abactinal pedi- 

 cellariae; madreporic body surrounded by 5 or 6 plates instead of 4. 

 The marginals of N. ternalis Porrier are conspicuously tumid and the 

 oral spines only 9. Perrier states that the apophysis starts at the 

 twenty-fourth adambulacral plate, while m moluccanus the angle is 

 well marked on the fifth plate and is apparent even before that. 

 However, a specimen from the United States National Museum, taken 

 at station 2398, referred to N. ternalis^ has the apophysis {^^ saillifi 



