STARFISHES OF THE PHILIPPINE SEAS. 539 



135+mm., r=9 mm.; breadth of ray at base, 4.5 mm.; length of 

 genital region, 30-35 mm. 



Description. — Disk fairly large with a beveled margin; disk plates 

 not distinguishable; spinelets delicate, sharp, but invested in a sheath 

 which causes them to appear terete and blunt. They are mostly 

 solitary — that is, are not in groups — and form an evenly spaced, 

 uniform, delicate nap, free from pedicellariae. The spinelets on the 

 margin of disk are a little longer than those at or near the center. 



Genital region of ray relatively short, slightly swollen, the spinelets 

 in clusters of 2 to about 6 per plate. On all but the basal fourth of 

 the genital region there are low, transverse, parallel ridges, spaced 

 about 1 mm. apart, formed of very slightly elevated plates bearing 

 most of the short, tapering, sharp spinelets. The spinelets have the 

 appearance of being collected into these transverse bands, while the 

 interspaces have very few spinelets yet there is no regularity in the 

 arrangement of the spinelets on the plates. They may form clusters 

 or short series, oriented obliquely, longitudinally, or transversely 

 with reference to the main axis of ray. These transverse bands of 

 spines resemble somewhat the costae of Brisinga, but are much less 

 prominent. 



A slender acicular spine, arising from a convex lateral plate fused 

 to the side of every adambulacral plate (usually a little aborad of 

 the middle), beginning with the eighth, increases in length until 

 equal to about G or 7 adambulacral plates (at a short distance beyond 

 end of genital region). 



Beyond the genital region or area of abactinal plating the integu- 

 ment is excessively thin, so that the underlying ambulacral ridge is 

 clearly visible, and it is crossed at each lateral spine by an inconspic- 

 uous band of pedicellariae, usually only with difficulty discernible 

 on the middorsal area. 



Adambulacral armature : one furrow spine at each end of the plate, 

 and a little shorter than the midventral length of the plate ; above the 

 aboral spinelet, a slender but yet stouter and longer spinule, about 

 1.6 plates in length, measured along the midactinal line. These 3 

 spinelets bear at the tip a group of slender- jawed, major pedicellariae. 

 On the actinal surface is a prominent subambulacral spine, which, on 

 the first 10 plates is conspicuously spatulate, gradually lengthening 

 from about the fourth, and narrowing at the tip from the sixth to 

 eighth plates. The broad tip is sometimes flat, sometimes scoop- 

 shaped, sometimes grooved, while the truncated end has often two or 

 three knobs. The knobs become more evident beyond the eighth 

 plate, most of the spines being practically bicapitate. The thirteenth, 

 fourteenth, and fifteenth are very long, slender, and tapering, with 

 either a capitate or a bicapitate tip, while beyond the thirteenth to 

 fifteenth (according to the ray), the spines lose the capitate tip and 



