400 PROCEEDIl^GS OF THE NATIONAL MUSEUM. vol. xxxvi. 



Family TROPIOMETRID^. 

 Genus CALOMETRA A. H. Clark. 



CALOMETRA CARDUUM A. H. Clark. 



One fine specimen from station 5166; off Simonor Island; 97 

 fathoms. 



Genus PTILOMETRA A. H. Clark. 



PTILOMETRA PULCHERRIMA, new species. 



Centro-dorsal large, columnar, the sides parallel, terminated by a 

 group of five large tubercles each radial in position, arising from an 

 otherwise flat polar area ; small circular space bounded by the ends of 

 these tubercles light in color, this light color extending in interradial 

 lines between the summits of the tubercles and thence to the periphery 

 of the polar area ; cirrus sockets arranged in ten columns of three or 

 four each, the radial areas being separated from each othei' by a low, 

 rounded ridge, and the pairs of columns in each radial area being- 

 separated by a broad, shallow^ groove about twice as broad as the 

 rounded interradial ridges. The centro-dorsal is 5 mm. long and 

 6 mm. in diameter. 



Cirri long and slender, XXXV, 80-85 (the less developed as few as 

 68), 75 nun. to 80 nun. long; first joint short, second about twice as 

 broad as long, the following gradually increasing in length to the 

 sixth or seventh, which is as long as broad ; following fifteen to twenty 

 joints between one-third and one-half again as long as broad, then 

 very slowly decreasing in length, the terminal thirty to thirty-five 

 joints being about twice as broad as long; the cirri are somewhat com- 

 I^ressed distally; after the seventeenth to the twentieth joint the 

 median part of the distal dorsal edge begins to project as a sharp 

 and slender spine, directed diagonally forward ; this spine gradually 

 increases in length, at the same time arising from more and more of 

 the dorsal surface of the joints, on the short distal joints arising from 

 their entire dorsal surface, with a slightly convex proximal and more 

 strongly concave distal edge, equaling in height about one-half the 

 vertical diameter of the joints; terminal eight or ten joints tapering 

 rather rapidly, at the same time increasing slightly in proportionate 

 length, so that the antepenultimate and penultimate joints are very 

 small and about as long as broad ; opposing spine equal in length to the 

 diameter of the penultimate joint, blunt, the distal edge forming a 

 straight line with the distal edge of the penultimate joint, arising 

 from nearly or quite the whole of the dorsal surface of that joint ; 

 terminal claw slightly longer than the penultimate joint, compara- 

 tively stout and strongly curved. 



Disk naked; all but one of the ambulacra (which divides immedi- 

 ately) are given off in well-separated pairs, so that nine ambulacral 



