512 BULLETIN 82, UNITED STATES NATIONAL MUSEUM VOLUME 1 



f 1 . Centrodorsal fairly high, the ratio of diameter to vertical height being about 1.2:1; 

 the surface between the cirrus sockets is flat (north of Sumbawa, East Indies; 2060 



meters) minima (p. 526) 



P. Centrodorsal low, the surface between the cirrus sockets convex (south of Celebes; 



1158 meters) anomala (p. 526) 



(P. Interradial areas much wider than the individual peripheral sockets (southwest of Akyab, 

 Burma; 497 meters) gracillima (p. 528) 



PSATHYROMETRA FRAGILIS (A. H. Clark)* 



[See vol. 1, pt. 1, figs. 110 (p. 176), 209-211 (p. 241), 286 (p. 262), 379 (p. 301), 502 (p. 369) ; pt. 2, 



figs. 91, 92 (p. 62)] 



A nledon fragilis A. H. CLARK, Proc. U.S. Nat. Mus., vol. 33, 1907, p. 80 (description; Albatross sta. 



5032). SOWERBY, The naturalist in Manchuria, Tientsin, vol. 5, 1930, p. 79. 



Psathyrometra fragilis A. H. CLARK, Smithsonian Misc. Coll., vol. 50, pt. 3, 1907, p. 353 (listed) ; Proc. 

 U.S. Nat. Mus., vol. 34, 1908, p. 274, fig. 3 (centrodorsal and radial articular faces) ; Crinoids 

 of the Indian Ocean, 1912, p. 234 (synonymy; locality); Journ. Washington Acad. Sci., vol. 5, 

 1915, No. 6, p. 213 (originally antarctic; entered the Sea of Japan from the northeast), p. 215 

 (antarctic; range and its significance) ; Die Crinolden der Antarktis, 1915, p. 115 (range). F. W. 

 CLARK and WHEELER, U.S. Geol. Surv. Prof. Paper 102, 1917, p. 20 (Albatross sta. 5032; in- 

 organic constituents of skeleton). A. H. CLARK, Unstalked crinoids of the Si&ogo-Exped., 1918, 

 p. 223 (in key; range), p. 226 (references). F. W. CLARKE and WHEELER, U.S. Geol. Surv. Prof. 

 Paper 124, 1922, p. 17 (inorganic constituents of skeleton). A. H. CLARK, Explorations des mers 

 de 1'U.R.S.S., vol. 23, 1937, p. 217 (widely distributed in N. Pacific), p. 218 (in key), p. 219 

 (localities; range), pp. 221, 222 (in Russian); pp. 223, 224, 225, 229, 230. VINOGRADOV, Mem. 

 Sears Found. Mar. Res., vol. 2, 1953, p. 256 (skeletal composition). BARANOVA, Invest. Far 

 East Seas U.S.S.R., No. 4, 1957, p. 152 (occurrence in Bering Sea; distribution), p. 248. 



Psalhyrometra borealis A. H. CLARK, Proc. U.S. Nat. Mus., vol. 34, 1908, p. 236 (description; Albatross 

 sta. 4780); Crinoids of the Indian Ocean, 1912, p. 234 (synonymy; locality); Die Crinoiden der 

 Antarktis, 1915, p. 115 (range); Unstalked crinoids of the iSi'6o<?a-Exped., 1918, p. 223 (in key; 

 range), p. 226 (references); Explorations des mers de 1'U.R.S.S., vol. 23, 1937, p. 217 (synonym 

 of P. fragilis), p. 223. GISLEN, Rep. Swedish Deep Sea Exped., vol. 2, Zool., No. 4, 1951, p. 56 

 (depth range). 



Psathyrometra profundorum A. H. CLARK, Proc. U.S. Nat. Mus., vol. 34, 1908, p. 237 (description; 

 Albatross sta. 3342); Crinoids of the Indian Ocean, 1912, p. 235 (locality); Die Crinoiden der 

 Antarktis, 1915, p. 115 (range) ; Unstalked crinoids of the Siboga-Exped., 1918, p. 226 (synonym of 

 P. borealis); Explorations des mers de 1'U.R.S.S., vol. 23, 1937, p. 217 (synonym of P. fragilis) , 

 p. 223. 



Psathyrometra, sp. A. H. CLARK, Die Crinoiden der Antarktis, 1915, p. 115 (Albatross sta. 4537); 

 Explorations des mers de 1'U.R.S.S., vol. 23, 1937, p. 217 ( = P. fragilis) (in Russian), p. 223. 



Psathyrometra alascana A. H. CLARK, Unstalked crinoids of the Siboga-Exped., 1918, p. 223 (in key; 

 range), p. 226 ("description in press"; nomen nudum); Explorations des mers de 1'U.R.S.S., vol. 

 23, 1937, p. 217 (synonym of P. fragilis), p. 223. 



Psathyrometra borealis TORTONESE, Natura, Milano, vol. 24, 1933, p. 164. 



Antedon (Psathyrometra) fragilis A. H. CLARK, Explorations des mers de 1'U.R.S.S., vol. 23, 1937, 

 p. 217 (in Russian), p. 223. 



Diagnostic features. The centrodorsal is nearly always markedly higher than 

 broad at the base, conical with the apex more or less broadly rounded; rarely it is only 

 a little higher than wide; there are three or four crowded, or more or less separated, 

 columns of cirrus sockets in each radial area with narrow bare interradial areas between ; 

 the arms are up to 130 mm. in length, and the cirri are 45 to 60 mm. in length with 

 25 to 35 segments; P 2 is shorter than PI. 



*See also Addenda (p. 836) under 1962. 



