A MONOGRAPH OF THE EXISTING CRINOIDS 149 



opposing spine; P 2 resembles P! and is only very slightly smaller, and the segments of 

 the genital pinnules are not expanded. 



Geographical range. — Known only from south of Lombok, in the Lesser Sunda 

 Islands. 



Bathymetrical range. — Known only from 1,097 meters. 



Remarks. — The genus Leilametra is closely related to Thalassometra from which it 

 differs in the long straight cirri the distal segments of which are without dorsal processes 

 and in having P 2 resembling P, instead of P 3 and the following pinnules. The relation 

 between Leilametra and Thalassometra is somewhat analogous to that between Craspe- 

 dometra and Heterometra. 



LEILAMETRA NECOPINATA A. H. Clark 



Plate 16, Figures 48, 49 



Leilametra necopinala A. H. Clark, Ann. Mag. Nat. Hist., ser. 10, vol. 10, No. 58, October 1932, p. 378 

 (listed), p. 379 (south of Lombok, 600 fathoms; description), pi. 13; Proc. Biol. Soc. Washington, 

 vol. 47, Feb. 9, 1934, p. 10 (new genus and species discovered by The Cable). 



Description. — The centrodorsal is of moderate size, apparently columnar basally, 

 with the bare dorsal pole low, rounded, conical, 3 mm. in diameter. The cirri are ar- 

 ranged in 10 columns of 2, rarely 3, each, the columns being closely crowded, though the 

 proximal cirrus sockets are somewhat more separated in the radial than in the interradial 

 lines. 



The cirri are XXII, 55-83 (in the longest cirri nearer the latter), up to 90-95 mm. 

 in length, and slender. They are of uniform width in the proximal half, in the distal 

 half very slowly and almost imperceptibly tapering to a fine tip. The first segment is 

 very short, the second and third are about three times as broad as long, the fourth is 

 twice as broad as long, the fifth is longer, nearly as long as broad, the sixth is about one- 

 third again as long as broad, and the seventh, which is a transition segment, is about 

 twice as long as broad or slightly longer. The next three or four segments are of the same 

 length, after which the length of the segments very slowly decreases so that those in the 

 distal half of the cirri are from half again to twice as broad as long, the terminal segments 

 again increasing in length so that the antepenultimate is about as long as broad. After 

 the transition segment the distal ends of the segments dorsally become slightly produced 

 and very finely spinous, at first only in the central portion, but later more and more 

 extensively, finally involving the entire distal edge on the dorsal side. The dorsal 

 profile of the segments is straight, distally becoming somewhat convex, and rises from 

 the proximal to the distal end, so that the dorsal profile of the cirri as a whole is serrate. 

 But the dorsal surface of the cirri is always broadly rounded, never becoming carinate. 

 There is no opposing spine. The terminal claw is long, longer than the segment that 

 bears it, slender, evenly tapering, and slightly and eveidy curved. 



The ends of the basal rays are conspicuous as rhombic areas in the interradial 

 angles of the calyx. Deep but narrow subradial clefts are present. 



The radials are short and bandlike, about eight times as broad as long in the 

 median line, shorter laterally than in the median line, evenly curved, and with the 

 median portion raised into a low and very broadly rounded elevation. The IBri are 

 about four times as broad as long, with the proximal and distal edges parallel and the 

 lateral borders produced so as to be in contact and more or less broadly swollen. The 

 anterolateral angles are broadly truncated, so that a rather narrowly rhombic water- 



