268 BULLETIN 82, UNITED STATES NATIONAL MUSEUM 



The pinnule ambulacra are heavily plated. 



Remarks. Mr. John said that, unlike most of the other species of the genus, the 

 IBrj and IBr 2 of P. sparksi are not raised into prominences big enough to be called 

 "tubercles" or "carinations." Perissometra crassa from the Kei Islands has no promi- 

 nences, and those of P. occidentalis from near the Seychelles are low. It is perhaps 

 the latter species that P. sparksi most nearly resembles. The shapes of the ossicles 

 of the division series are similar in both. But there are many differences, and the 

 two species may be separated by the cirri alone those of P. sparksi are composed 

 of longer segments and are longer and smoother than those of P. occidentalis. 



Locality. Northwest of Sokotra (lat. 1420' N., long. 5230' E.); 2,194 meters; 

 Capt. V. F. Sparks, cable repair ship Electra, July 1909 [A. H. Clark, 1911, 1912, 1913, 

 1937; John, 1937] (1, B. M.). 



History. During a visit to the British Museum in 1910 I examined the type 

 specimen of this species, but did not have time to draw up a description of it. I men- 

 tioned it as Pachylometra, n. sp., in 1911, 1912, 1913, and 1937. It was formally described 

 by D. Dilwyn John in 1937. 



GLYPTOMETRA SCLATERI (Bell) 



Antedon sclateri BELL, Marine investigations in South Africa, vol. 4, pt. 4, 1905, p. 140 (description; 

 East London, NW. 1/2 N., 18 miles; 250-300 fathoms), pi. 3, figs. 1-3. A. H. CLARK, Proc. 

 Biol. Soc. Washington, vol. 21, 1908, p. 126 (belongs to Charitometra, near inaequalis) ; Proc. 

 U. S. Nat. Mus., vol. 34, 1908, pp. 437, 493 (described in the Savignyi group; really belongs in 

 the Granulifera group and is very close to inaequalis) ; vol. 40, 1911, p. 5 (identity); Crinoids 

 of the Indian Ocean, 1912, p. 40 (identity). 



Charitometra sclateri A. H. CLARK, Proc. Biol. Soc. Washington, vol. 21, 1908, p. 126 (belongs in 

 Charitometra, near inaequalis). 



Pachylometra sclateri A. H. CLARK, Proc. Biol. Soc. Washington, vol. 22, 1909, p. 21 (listed); Proc. 

 U. S. Nat. Mus., vol. 40, 1911, p. 5 (identity), p. 8 (southeast coast of Africa), p. 38 (synonymy; 

 locality); Crinoids of the Indian Ocean, 1912, p. 40 (identity), p. 216 (synonymy; locality); 

 Smithsonian Misc. Coll., vol. 61, No. 15, 1913, p. 48 (published reference to specimens in the B. M. ; 

 stations 12676, 12711, 12792, 12885/6; no loc.; characters of the centrodorsal) ; Die Crinoiden 

 der Antarktis, 1915, p. 164 (represents the family Charitometridae in South Africa; range); 

 Unstalked crinoids of the Siboga-Exped., 1918, p. 184 (in key; range), p. 185 (references). 

 H. L. CLARK, Ann. South African Mus., vol. 13, pt. 7, No. 12, 1923, p. 234 (new localities; charac- 

 ters of 10-armed young). GISL^N, Ark. Zool., vol. 19, No. 32, Feb. 20, 1928, p. 8, No. 38 (notes). 

 A. H. CLARK, John Murray Exped. 1933-34, Sci. Reports, vol. 4, No. 4, 1936, pp. 101 (range), 

 105. GiSLfiN, Kungl. Svenska Vet. Akad. Handl., ser. 3, vol. 17, No. 2, Oct. 3, 1938, p. 4, p. 18 

 (localities; notes), figs. 16, 17, p. 19, pi. 2, fig. 7. 



Diagnostic features.- The cirri are arranged in 10 columns on the centrodorsal; 

 they are 18-20 mm. long with 16 segments of which all but the basal are longer than 

 broad; there are 11-17 arms; and the division series and arm bases are smooth and very 

 broad. 



Description. Bell's original description is as follows: 



This somewhat variable species appears to belong to Division II of Carpenter's A. savignyi 

 group (see Chall. Report Comat., p. 252). There are not as many as 20 joints in the cirri, and may 

 be no more than 15, the distichal pinnule is small, and there are no lateral processes to the pinnules; 

 there are 20 arms or less, but always more than 10. 



The cirri vary not only in the number of joints, but in the length of them, so that what appear 

 to be fully developed cirri may be less than 15 or more than 30 mm. long; the increase in length is 

 due rather to the increased length of the joints than to an increase in number. 



