PART 5 A MONOGRAPH OF THE EXISTING CRINOIDS 785 



Tho interradials have a swollen surface, especially distally, but none of thcna 

 show an}' indications of an appendage. 



On the arms syzygies occur between brachials 4+5, 10 + 11, and 14 + 15. 



The pinnule on tho thii-d brachial (P,) has 13 segments, of which tho first is twice 

 as broad as long, the second is slightly broader than long, the third is from a third to 

 a half again as long as broad, and the remainder are about tlirec times as long as broad. 



The five orals are relatively slightly'- smaller than in tho young of T. renovatus 

 described by Carpenter. The perisomic areas are occupied by numerous plates which 

 are largest proximally and in the center of the areas, becoming smaller on the sides 

 and toward tho orals. These plates are more or less separated from each other, 

 evidently as a result of a distension of the visceral mass. There is no indication that 

 there ever was any imbrication such as is suggested by Carpenter's figures. The 

 anal tube is conspicuous and C3-Iindrical, and is thickly studded with small plates. 



Localities. — IngolJ station IS; southwest of Iceland (lat. 61°44' N., long. 30°29' 

 W.); 2075 meters; temperature 3.0° C. [A. H. Clark, 1915, 1918, 1921, 1923; Gislen, 

 1924] (40, U.S.N. M., E. 1089; CM.). Type locahty. 



IngolJ station 97; Denmark Strait, between AngraagsaUk, Greenland, and north- 

 western Iceland (lat. 65°28' N., long. 27°39' W.); 823 meters; temperature 5.5° C. 

 [A.H.Clark, 1923] (1, CM.). 



Remarks. — This is the only species of the genus known from the Atlantic, and 

 also the only species which has ever been dredged in quantity. 



It is not absolutely certain that the young individual from IngolJ station 97 

 belongs to this species, though the probabilities are that it does. 



Genus PENTAMETROCRINUS A. H. Clark* 



Ophiocrinus (part) P. H. Carpenter, Nature, vol. 15, 1877, p. 198; vol. 19, 1879, p. 450; Proc. Roy. 

 Soc, vol. 28, No. 194, 1879, p. 384; Quart. Journ. Geol. Soc, vol. 36, 1880, p. 41 (subgenus of 

 Antedon; all recent material in Carpenter's possession), p. 45 (no b.asal rays); Bull. Mus. Comp. 

 Zool., vol. 9, No. 4, 1881, p. 161; Journ. Linn. Soc. (Zool.), vol. 16, 1882, p. 494; Phil. Trans. 

 Roy. Soc. for 1883, pt. 3, 1884, p. 919, footnote (preoccupied; name changed to Eudiocrinus) . — 

 A. H. Clakk, Proc. U.S. Nat. Mus., vol. 34, 1908, pp. 34, 271 (history and status of the name). 



Eudiocrinus (part) P. H. Carpenter, Journ. Linn. Soc. (Zool.), vol. 16, 1882, p. 493 (new name for 

 Ophiocrinus Semper, 1868 [not Ophiocrinus Salter, 1856]) ; Proc. Roy. Soc, vol. 35, No. 225, 1883, 

 p. 138 (comparison with Thaumatocrinus). — Perrier, Compt. Rend. Acad. Sci., vol. 96, No. 11, 

 1883, p. 725. — P. H. Carpenter, Phil. Trans. Roy. Soc. for 1883, pt. 3, 1884, p. 919 (comparison 

 with naumatocrinus), p. 920 (referred to the Comatulidae) ; Chnlleiiger Reports, Narrative, 

 vol. 1, pt. 1, 1885, p. 310. — Perrier, Explorations sous-marins, 1886, p. 275. — P. H. Carpenter, 

 Quart. Journ. Micr. Sci., new ser., vol. 27, 1887, p. 385; vol. 28, 1887, p. 308 (homologies with 

 ophiurans); Challenger Reports, Zoology, vol. 26, pt. 60, 1888, p. 73 (general account). — Bather, 

 Proc. London Amateur Sci. Soc, vol. 1, Nos. 1, 2, July 1890, p. 33 (mode of attachment). — 

 Perrier, Trait6 de Zoologie, 1893, pp. 784, 794, 858. — Bather, Proc. Zool. Soc. London, 1895, 

 p. 995 (comparison of base with that of Uiniacrinus) . — Lang, Text book of comparative anatomy, 

 vol. 2, 1896, p. 313. — Bather, in Lankester, A treatise on zoology, pt. 3, Echinoderma, 1900, 

 pp. 135, 137, 195. — Delage and Herouard, Trail6 de Zoologie concrete, vol. 3, 1903, p. 394. — 

 MiNCKERT, Arch. Naturg., Jahrg. 71, Heft 1, 1905, p. 166 (syzygies; regeneration). — IIamann, 

 Bronn's Klassen und Ordnungen des Tier-Reiclis, vol. 2, Abt. 3, 1907, p. 1575. — A. II. Clark, 

 Proc U.S. Nat. Mus., vol. 32, 1907, pp. 569, 573; Smithsonian Misc. Coll., vol. 50, pt. 3, 1907, 

 pp. 343, 344; Proc. Biol. Soc. Washington, vol. 21, 1908, p. 134; Proc. U.S. Nat. ^rus., vol. 34, 

 1908, pp. 210, 212, 269, 271, 276.— Vanet, Bull. Mus. Hist. Nat., Paris, No. 3, 1910, pp. 160, 



♦See also Addenda (p. 830) under 1962. 



