262 BULLETIN 82, UNITED STATES NATIONAL MUSEUM 



to P 6 . From C. parvula it differs in its more spinous brachials and pinnule segments, 

 somewhat greater slenderness, especially of the cirri, and in having the second cirrus 

 segment usually slightly longer, this feature being particularly distinct in the long- 

 est ventral cirri. 



History. This species was originally described from a specimen from the Siboga 

 collection in 1912. A more detailed description, with figures, was published in 1918, 

 when a second specimen smaller than the type, but otherwise resembling it, was also 

 recorded. 



In 1922 Dr. Torsten Gisle"n recorded Comissia parvula from a number of locali- 

 ties off southwestern Japan, where it had been secured by Dr. Sixten Bock in 1914. 

 In 1924 he referred to one of Bock's specimens as "Comissia cf. spinosissima," and in 

 1927 he recorded C. spinosissima from 3 of Dr. Th. Mortensen's stations southwest 

 of the Goto Islands, and also mentioned that the specimen from Bock's station 8 

 originally referred to C. parvula should have been referred to this species. 



COMISSIA PARVULA A. H. Clark 



Plate 28, Figure 77 



Comissia parvula A. H. CLARK, Proc. Biol. Soc. Washington, vol. 25, 1912, p. 19 (description; 

 East Indies; Siboga); Unstalked Crinoids of the Siboga Exped., 1918, p. 20 (in key; range); 

 p. 23 (detailed description; stations 95, 105, 294, 302; no locality; also Albatross stations 5162, 

 5629); pp. 272, 273, 275, 276 (listed); pi. 13, fig. 9. GISLEN, Nova Acta reg. Soc. sci. Upsalien- 

 sis, ser. 4, vol. 5, No. 6, 1922, p. 4 (209-728 m.); p. 5 (Sagami Bay); p. 6 (Kiu-Shiu and the 

 Goto Is.; previous records); p. 23 (Bock's stations 4, 8, 36, 37; description of specimens); figs. 

 12-14, p. 28; Zool. Bidrag fran Uppsala, vol. 9, 1924, p. 41 (details of arms). 



Diagnostic features. The cirri are XX-XXIII, 9-13 (usually 11), from 7 to 9 

 mm. long; the longest cirrus segment is three times as long as broad. The arms are 

 from 45 to 50 mm. (but seldom over 45 mm.) in length. The edges of the elements 

 of the division series are smooth and not produced. The distal edges of the brachials 

 and pinnule segments are not unusually spinous. The comb on PI is composed of 9 

 teeth, which are about as high as the width of the segments bearing them. P 4 does 

 not bear a comb. 



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

 from 2 to 2.5 mm. in diameter. The cirrus sockets are arranged in 2 marginal rows. 



The cirri are XX-XXIII, 9-13 (usually 11), from 7 to 9 mm. long, resembling 

 those of C. hispida but slightly more slender. 



The 10 arms are 45 mm. long, and slender. 



Notes. The specimens from Siboga station 302 have 9-11 cirrus segments and 

 resemble the following. 



The specimens from Siboga station 294 have the cirri with 10 segments, 6 mm. 

 long; the arms are 45 mm. long. 



In the specimen from the Danish expedition to the Kei Islands station 4 the 

 centrodorsal is discoidal, very thin, the almost flat dorsal pole with a slight very 

 broadly conical elevation in the center. The cirrus sockets are arranged in 3 closely 

 crowded and very irregular marginal rows, of which the innermost, due to the strongly 

 sloping sides of the centrodorsal, seems to be situated on the dorsal surface. 



The cirri are numerous, XXXIII, 12-13, rather slender, 10 mm. long. The first 

 segment is twice as broad as long, the second is two and one-half or three times as 



