A MONOGRAPH OF THE EXISTING CRINOIDS 45 



The 24-26 arms are probably over 100 mm. long. The first two brachials are prom- 

 inently carinate, like the elements of the division series. Their borders are practi- 

 cally unmodified, or are very slightly and rather broadly thickened. There is a 

 prominent water pore between the adjacent first two brachials on each arm pair, 

 formed chiefly by the cutting away of the proximal inner angle of the second brachials. 

 A low but prominent median carination, abruptly set off from the dorsal surface of the 

 brachials, runs along the arms to the tip. 



Pi is slender and not greatly stiffened, 10 mm. long with 17 segments. The 

 first segment is about as long as broad, the second is slightly longer than broad, the 

 third is nearly half again as long as broad, and those following slowly and gradually 

 increase in length so that the fourteenth is twice as long as broad and the sixteenth 

 is about three times as long as broad. The distal ends of the segments are very slightly 

 prominent, though not everted or otherwise modified, and the distal angles on the side 

 toward the arm tip are slightly produced, overlapping the base of the segment following. 



P 2 is 8 mm. long with 15 segments and resembles Pi. P 3 is 7 mm. long with 12 

 segments and resembles P 2 . P4 is 5 mm. long with 12 segments. 



The lower pinnules are all about equally stout basally, and aU taper slowly and 

 evenly to the tip. 



Notes. — In one of the specimens dredged by the Mabahiss the 23 arms are 95-100 

 mm. long. The cirri are XVIII, 36-39, 30-35 mm. long; the transition segment is 

 usually the ninth, sometimes the tenth. The division series resemble those of the two 

 original specimens from south of Ceylon, but the elements of the IBr series are often 

 somewhat rugose laterally, with the distal border of the IBri, and also of the IIBri, 

 coarsely scalloped laterally. 



Another individual has 28 arms 90 mm. long. The division series have a slightly 

 irregular surface. 



In an example with 24 arms the dorsal surface of the division series is scarcely 

 modified. 



Other specimens have 25, 24, 23, 23, 20, and 15 arms, the two last being small. 

 There are four additional examples. 



Color in life. — A note made at the time of capture of the Mabahiss specimens de- 

 scribes the color, on the basis of Ridgway's " Color Standards and Color Nomenclature," 

 as "orange with the aboral surface white." 



Remarks. — Cosmiometra leilae appears to be most closely related to C. delicata from 

 the Hawaiian Islands, but it is a much stouter species with a much broader and lower 

 centrodorsal on which the cirri are arranged in 15 instead of in 10 columns, the transition 

 segment in the cirri is the eighth instead of the sixteenth, and the carination of the 

 brachials is higher, narrower, and more conspicuous. 



Localities.— Investigator station 465; south of Ceylon (lat. 5°56' N., long. Sl°22' E.) ; 

 199-241 meters; April 22, 1912 [A. H. Clark, 1932] (2, U.S.N.M., E. 3271 ; I. M.'j. 



Mabahiss station 157; Maldive area (lat. 4°43'48" N., long. 72°55'24" E. to lat. 

 4°44'00" N., long. 72°54'18" E.); 229 meters; April 6, 1934 [A. H. Clark, 1937] (13, 

 B. M.; Cairo Mus.). 



History.— Cosmiometra leilae was described in 1932 from two specimens that had 

 been dredged in 1912 by the Royal Indian Marine Survey steamer Investigator at 

 station 465, south of Ceylon. In January 1937, 13 additional specimens were recorded 



