A MONOGRAPH OF THE EXISTING CRINOIDS 139 



with C. prashadi); John Murray Exped. 1933-34, Sci. Reports, vol. 4, No. 4, 1936, p. 100 (syn- 

 onyrn of C. manca). 



Cyllomelra disciformis A. H. Clark, Crinoids of the Indian Ocean, 1912, p. 34 (identity), p. 158 

 (synonymy ; locality) ; Smithsonian Misc. Coll., vol. 61, No. 15, 1913, p. 34 (published reference to 

 specimens in the B. M.; locality; cirrus characters); Unstalked crinoids of the Sihnga Exped., 

 1918, p. 114 (in key; range), p. 116 (discussion; Alhalroas stations 5213, 5212, 5356, 5369, 5154 

 Cebu reefs). — Gisl£n, Nova Acta Reg. Soc. Sci. Upsaliensis, ser. 4, vol. 5, No. 6, 1922, p. 4 

 (162-728 m.), p. 5 (Sagami Bay), p. 6 (Bonin Islands), p. 7 (previous records), p. 9, p. 77 (Bock's 

 stations 12, ?33, 35; detailed notes), p. 84, pp. 180, 181 (listed), figs. 68, 69, p. 88; Zool. Bidrag 

 Uppsala, vol. 9, 1924, p. 41 (measurements), pp. 44, 79; .■Vrk. Zool., vol. 19, No. 32, 1928, p. 6, 

 No. 20 (notes on specimens in the B. M.) ; Kungl. Fysiogr. Sallsk. Uandl., new ser., vol. 45, No. 

 11, 1934, p. 20. 



Antedon albopurpurea Hartlaub, Mem. Mus. Comp. Zool., vol. 27, No. 4, 1912, p. 381 (listed). 



Antedon anomala Hartlaub, Mem. Mus. Corap. Zool.. vol. 27. No. 4, 1912, p. 381 (listed). 



Cyllomelra pulchella GisLfiN, Nova Acta Reg. Soc. Sci. Upsaliensis, ser. 4, vol. 5, No. 6, 1922, p. 4 

 (136-163 m.), p. 6 (Kiu Shiu and Goto Islands), pp. 9, 10 (constancy of characters), p. 84 

 (Bock's stations 6, 12, 13, 16, 17; detailed notes), pp. 110, 131, 180 (listed), p. 181, figs. 133-140, 

 p. 134, pi. 1, fig. 9; Zool. Bidrag Uppsala, vol. 9, 1924, po. 20, 21 (Mortensen's station 10; 

 abnormal arm), p. 22 (distal arm branching), p. 285 (Kiu Shiu, about 200 m.; details), p. 286; 

 Vid. Medd. Dansk Naturh. Foren., vol. 83, 1927, p. 2 (occurrence of IIBr series; Mortensen's 

 stations 7, 9, 10, 11; [0-] 135-180 m.), p. 23 (stations 7, 10; notes), p. 25 (comparison with C. 

 albopurpurea), pp. 26, 68 (listed); Kungl. Fysiogr. Sallsk. Handl., new ser., vol. 45, No. 11, 

 1934, p. 20. 



Petasometra anomala Gisl^n, Kungl. Fysiogr. Sallsk. Handl., new ser., vol. 45, No. 11, 1934, p. 27 



Diagnostic features. — -The cirri have usually 18-26 (most commonly about 21-22) 

 segments, and are most frequently 8-9 mm. long; the longest cirrus segnaents are from 

 about as long as broad to half again as long as broad; the 10-30 arms are usually 

 25-95 (most commonly 30^5) mm. long. 



Description. — The centrodorsal varies from a thin disk to a flattened hemisphere, 

 being usually a moderately thick circular or more or less pentagonal disk up to 4.5 

 mm., but usually between 2 and 3 mm. in diameter, with sloping sides and the usually 

 flat, but sometimes sUghtly convex or slightly concave, dorsal pole from 1 to 3, usually 

 about 2, mm. in diameter. The cirrus sockets are arranged in from 1 to 2 more or less 

 irregular crowded and more or less alternating rows. 



The cirri are XV-XXXI (usually between XX and XXVIII), 12-35 (usually 

 18-26 and most commonly about 21-22), from 5 to 21 (usually between 7 and 11 and 

 most commonly 8 or 9) mm. long. The first two or three segments are broader than 

 long, the third or fourth, or both, is about as long as broad, the next is somewhat 

 longer, and those following vary from about one-third again as broad as long to twice 

 as long as broad, being usually slightly longer than broad; the distal segments are 

 shorter again, from half again as broad as long to one-third again as long as broad, 

 being usually about as long as broad or slightly shorter. Although usually the 

 segments in the proximal half of the cirri are slightly longer than broad and those in 

 the distal half are shghtly broader than long, sometimes all the segments are practi- 

 cally subequal, all being about as long as broad or slightly broader than long. Tlie 

 antepenultimate segment is about as long as broad or a Uttle longer than broad. 

 Dorsal processes usually begin on about the sixth or seventh segment, but may begin 

 as early as the fifth or even the fotirth, or as late as the twelfth. These dorsal proc- 

 esses usually take the form of paired dorsal tubercles which most frequently are small 

 and occasionally very small, though sometimes rather high and conspicuous; but not 



