STAKFISHES OF THE PHILIPPINE SEAS. 65 



ASTROPECTEN PHRAGMORUS Fisher. 



Plate 11, fig. 5 ; plate 14, figs. 1, la-b. 



Astropeeten acanthifer phragmorus Fisher, 1913a, p. 604. 

 Astropecten phragmoius Douerlein, 1917, p. 178. 



Diagnosis. — Very similar to A. acanthifer Sladen, but differing in 

 having narrower rays; more perpendicular superomarginals, bearing 

 larger spines on the extreme upper and inner edge of plate (not 

 spaced conspicuously therefrom) ; a relatively longer actinal infero- 

 marginal spine and longer marginal spines generally (especially in 

 proportion to width of ray) ; an incipiently enlarged subambulacral 

 (more noticeable in young examples) . R=48 mm., r=8 mm., R=6 r ; 

 breadth of ray at second superomarginal, 9 mm. The brownish 

 marking seems to be distinctive also. 



Description. — Rays slenderer than in acanthifer although the disk 

 is no smaller. Sladen gives the proportions of the type as R=6.43 r, 

 but the figure shows proportions of R=between 5 and 6 r, nearer 5. 

 The narrower rays of the present species will be evident on a compari- 

 son of figures. Paxillar area very compact, the outlines of indi- 

 vidual paxillae being sometimes difficult to distinguish. The paxillae 

 are similar to those of acanthifer^ but the spinelets are a little longer 

 and slenderer, judging by the figure, although in the largest speci- 

 mens, numerically about the same. 



Superomarginal plates, about 35 in number, confined to side of 

 ray proximally and forming a steep bevel; encroaching more and 

 more upon the abactinal surface, and becoming relatively lower and 

 more arched on outer half of ray. In acaTifhifer the proximal plates 

 have a definite rounded angle between the dorsal and lateral surfaces, 

 and on this angle the small, superomarginal spine is situated. In 

 phragmorus the proximal plates slope very steeply, and nearly the 

 whole of the upper end is occupied by the base of the stout, tapering, 

 slightly flattened sharp spine, which, on the outer third of the ray, 

 withdraws slightly from the inner edge of the plate. The supero- 

 marginal spines of phragmorus are situated as the two to four inter- 

 brachial spines of acanthifer. The first spine is 3 mm. long, stouter 

 and longer than the rest, and slightly exceeds the height of plate; 

 and all along ray the spines preserve the same proportion to their 

 plate, as the plates become lower. They are much stouter and longer 

 than in acanthifer. General surface of plate covered with slightly 

 spaced spinelets, terete and blunt except in the middle where they are 

 a little stouter and more squamiform, increasing in size around the 

 base of spine. 



