A MONOGRAPH OF THE EXISTING CRINOIDS 361 



onal, not quite twice as broad as long. The dorsal surface is slightly excavated so that 

 the distal edges appear prominent. The thin produced ventrolateral border of the 

 IBf] is continued on to the IBr 2 where, viewed ventrally, it is seen to have its sides 

 parallel, and viewed dorsally it disappears beneath the produced lateral angles of the 

 axillary. The IBr! sometimes bear a small rounded tubercle just anterior to the 

 proximal half of the synarthrial tubercle. The IBr 2 have a more or less prominent 

 narrow rounded median carination running anteriorly from the base of the distal 

 half of the synarthrial tubercle, often terminating, approximately on a level with the 

 lateral angles, in a prominent tubercle. Both these features are repeated on the 

 ossicles of the IIBr series and on the first two brachials. The synarthrial tubercles 

 are small and narrow but greatly produced, as in Perometra diomedeae. They are 

 proportionately smaller and narrower than in that species, though nearly as high. 

 The IIBr series are 2. 



The 16 arms are about 70 mm. long. The brachials are essentially as in N. multi- 

 color, but each bears a prominent low, narrow, rounded carination which ends distally 

 in a more or less spinous production of the distal edge. This carination lies alternately 

 on either side of the median line, the alternation being most pronounced in the proxi- 

 mal part of the arm. 



P! is 10 mm. long, slender and weak, with from 28 to 33 segments of which the 

 first two are enormously enlarged and the remainder very small, about as long as 

 broad. P 2 is 13-15 mm. long, stiff, and spinelike, though rather slender, with 

 18-22 segments. P 3 is 17 mm. long with 20 segments, resembling P 2 but slightly 

 stouter and composed of slightly longer segments of which the first two are only 

 slightly enlarged. 



Localities. Siboga station 294; south of Timor (lat. 1012'16" S., long. 

 12427'18" E.); 73 meters; soft mud with very fine sand; January 23, 1900 [A. H. 

 Clark, 1912, 1918] (11, U.S.N.M., E. 476; Amsterdam Mus.). 



Siboga station 260; Kei Islands; 2.3 miles N. 63 W. from the northern point of 

 Nuhu Jaan (lat. 536'20" S., long. 13255'12" E.); 90 meters; sand coral and shells; 

 December 16, 1899 [A. H. Clark, 1918] (1, Amsterdam Mus.). 



Geographical range. From the Kei Islands to Timor. 



Bathymetrical range. From 73 to 90 meters. 



History. This species was described as Calometra diana in 1912, and was trans- 

 ferred to the genus Neometra in 1918. Various structural features were discussed by 

 Prof. Torsten Gisle"n in 1922, 1924, and 1934. As yet it is known only from Siboga 

 stations 260 and 294. 



NEOMETRA SAPPHO, new species 



Diagnostic features.- The dorsal processes on the outer cirrus segments consist 

 of a median keel only; the cirri are less than one-third the arm length with 38-41 

 segments of which the longest are nearly twice as long as broad; there are 14 arms 

 85 mm. long; synarthrial tubercles are not developed. 



Description. The centrodorsal is thin, discoidal, with the dorsal pole flat. The 

 cirrus sockets are arranged in a single regular marginal row. 



The cirri are VIII, 38-41, from 20 to 25 mm. long, slender and delicate. The 

 first segment is between two and three times as broad as long, the second is half 

 again as broad as long, the third is as long as broad or slightly longer than broad, and 



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