166 ECHINODERMA OF THE INDIAN MuSEUM, PART VII. 



COLOBOMETRA DISCOLOR. 

 Colobometra discolor 1909. A. H. Glabk, Proc. U. S. Nat. Mus., vol. 36, p. <>-t<'. 



Description.— Cirri XVIII-XXII, 29-40 (usually about 35), 25 mm. to 30 

 mm. long, slender, resembling those of C. perspinosa, but with the distal ends of 

 the segments not so strongly spinous. 



Radials projecting slightly beyond the edge of the centrodorsal ; IBr, 

 oblong, slightly over twice as broad as long, the ventrolateral edges slightly pro- 

 duced into a thin border by which they are in apposition ; IBr^ broadly pentago- 

 nal, .twice as broad as long, the lateral edges somewhat more than half the length 

 of those of the IBr,, making with them a straight hne, and with the same 

 ventrolateral projection; a slight constriction is usually present just below 

 the lateral angles. 



Ten arms SO mm. long, resembling in general those of C. suavis!. 



Pa absent ; P, ()-5 mm. long, small, tapering rapidly to a slender and delicate 

 tip^ with fifteen or sixteen segments ; first segment twice as broad as long, 

 second somewhat longer, third about as long as broad, the fourth similar, the 

 following very gradually increasing in length to about half again as long as 

 broad, and becoming squarish again in the terminal four or five; P.^ 15 mm. long, 

 moderately stout and very stiff and spine-like, with about twenty segments, the 

 first about twice as broad as long, the second slightly longer, the third nearly 

 half again as long as broad, the remainder about twice as long as broad ; begin- 

 ning on the second segment there is a faintly indicated broadly rounded keel 

 running along the middle of the outer side, as on P, ; on the third and following- 

 segments the distal dorsal edge projects in the line of this keel in a narrow fringe 

 of spines which broadens on succeeding .segments, the spines at the same time 

 becoming longer, and is supplemented by additiona 1 spines on the ventrolateral 

 angles of the segments; P.^ similar to P^, usually about 1 mm. shorter; P^ 

 10 mm. long, resembhng P, and P, though not quite so stiff, with fifteen segments ; 

 P^ and following pinnules very slowly decreasing in length and stiffness, at the 

 same time becoming more slender, with the spines on the distal ends of the seg- 

 ments less and less pronounced ; P^, is s mm. long and P,, is 7 nun. long, each 

 with fifteen segments; from this point the pinnules very gradually increase to 10 

 mm. distally, the distal pinnules being slender, comparatively little stiffened, 

 with from twenty to twenty-two segments whicli have moderately everted ends 

 armed with fine spines ; the distal pinnules are somewhat compressed laterally. 



The colour in spirits is purple, the arms thickly covered with yellow spots, 

 the cirri with occasional narrow yellow bands, the proximal pinnules mainly 

 yellow ; or, purple, the cirri and proximal pinnules yellow. 



Localities.— iVear Coco Island (14° 04 ' 30" N. lat., 9.3° 51' 00" K. long.) ; 

 41 fathoms (Type Locality).— Four specimens. 



Off noiiJi-eastern Ceylon (S° 51' .30" N. lat., Sl° 11' 52" E. long.); I'S fathoms. 

 — Three specimens. 



