STARFISHES OF THE PHILIPPINE SEAS. 529 



of ray at base, and midway between them is a broad band of micro- 

 scopic pedicellariae, with an incomplete band on either side of this, 

 proceeding from the adambulacral plates a variable distance toward 

 the median line. The costal ridges are also covered with pedicella- 

 riae, and beyond the costal region the broad bands occur quite regu- 

 larly opposite each lateral spine, with 1, rarely 2, between; hence 

 1 opposite each adambulacral plate. Lateral spines very prominent 

 and longer than in A. moluccana, which this species resembles. The 

 first spine, at the ends of the second or third rib, is quite short, 

 slender, and sharp. The succeeding spines often stand out rigidly 

 from the sides of the ray and occur regularly above every other 

 adambulacral plate articulated to a prominent boss of the lateral 

 plate. They attain their full length in the distal half of the costal 

 region, where they are about 20 mm, long, or the length of 7 to 8 

 consecutive adambulacral plates. 



Proximal adambulacral plates, viewed from the side, are distinctly 

 lower than long, and they are a trifle longer than broad. On account 

 of the adoral furrow spine, the margin appears deeply excavated. 

 The adambulacral armature consists of 1 true furrow spinelet at each 

 end, nearly as long as the plate, 1 adoral minor subambulacral 

 spinule a little longer than the plate, and a major subambulacral 

 spine situated on a prominence of the aboral half of the plate. It is 

 equal to 3| or 4 adambulacral plates in length and forms an oblique 

 series with the subambulacral spinule and the adoral furrow spine- 

 let. The formula is ^—y. On the outer part of the ray it is t 



or .+1. This armature resembles that of A. moluccana, but the 

 ^ ' 



actinal spinule is farther from the furrow and longer. The lateral 



and adambulacral spines have a thin felti'.ig of pedicellariae which 



are usually lacking on the side of the spine nearest furrow in the case 



of the big spines. 



The armature of the mouth plates is as follows: Directed over the 

 furrow at either end of the plate is a slender furrow spine, and mesad 

 to the inner one a little actinostomial marginal spine about half as 

 long; in the middle of the actinal surface is a tapering, sharp, glassy 

 tipped suboral spine about 2^ times the length of plate and sheathed 

 with membrane covered with pedicellariae. Between this and the 

 outer end of tlie plate there is usually a second subambulacral spine, 

 varying from slightly more than the length of the plate to the size 

 of the primary suboral. The suboral spines are usually bent over 

 the actinostome. 



Madreporic body circular, very prominent but flat-topped, with 2 

 nearly equal, naked or only slightly armed plates on its inner border. 



