A MONOGRAPH OF THE EXISTING CRINOIDS 151 



segments succeeding. The second and following segments bear high carinate processes 

 with the crest parallel to the axis of the pinnule. 



P 2 is 8 mm. long with 14 or 15 segments. It resembles PI and is only slightly 

 less stout basally. 



P 3 is 6 mm. long with 11 or 12 segments and resembles the pinnules preceding, 

 but is less stout. As in the preceding pinnules, the carinate processes on the segments 

 are well developed. 



P 4 is 6 mm. long with 10 segments and resembles P 3 , but the carinate processes 

 on the segments are not quite so strongly developed. 



P 6 is 6 mm. long with 10 segments and resembles P 4 . On the next few pinnules 

 the carinate processes on the segments disappear. 



The distal pinnules are 15 mm. long with 18 or 19 segments. 



The color is yellow with the basal portion of the cirri, including the proximal two- 

 thirds of the transition segment, darker, especially on the transition segment itself. 



Locality. South of Lombok Island (lat. 859'54" S., long. 11550'48" E.); 1,097 

 meters; cable repair ship The Cable, Eastern Australasia and China Telegraph Co. 

 [A. H. Clark, 1932, 1934] (1, B. M.). 



Genus THALASSOMETRA A. H. Clark 



Antedon (part) P. H. CARPENTER, Challenger Reports, Zoology, vol. 26, pt. 60, 1888, p. 107, and fol- 

 lowing authors. 



Thalassometra A. H. CLARK, Smithsonian Misc. Coll., vol. 50, pt. 3, 1907, p. 359 (diagnosis; geno- 

 type Antedon villosa A. H. Clark, 1907); Bull. Mus. Comp. Zool., vol. 51, No. 8, 1908, p. 245 

 (characters; genotype) ; Proc. Biol. Soc. Washington, vol. 21, 1908, p. 136 (referred to the Thalas- 

 sometridae) ; Proc. U. S. Nat. Mus., vol. 34, 1908, p. 211 (referred to the Thalassometridae), 

 p. 212 (occurs in Japan and the Crozet, Aleutian, Galdpagos and Hawaiian Islands), p. 275 

 (proximal ornamentation); Amer. Nat., vol. 42, No. 503, 1908, p. 723 (range; habitat); Geogr. 

 Journ., vol. 32, No. 6, 1908, p. 602 (range; habitat); Proc. Biol. Soc. Washington, vol. 22, 1909, 

 p. 1 (revision), p. 14 (list of species included in the genus as restricted); Vid. Medd. Naturh. 

 Foren. K0benhavn, 1909, p. 138 (transition segment in the cirri comparable to that of Comatella 

 maculata); Proc. U. S. Nat. Mus., vol. 39, 1911, p. 551 (Crotalomelra [Oceanomelra] annandalei 

 referred to this genus); vol. 40, 1911, p. 12 (occurs in deep water in the Atlantic, but does not 

 intrude on Polar-Pacific species) ; Crinoids of the Indian Ocean, 1912, p. 10 (2 species occur in 

 the Hawaiian Islands), p. 11 (occurs both east and west of Ceylon), p. 12 (represented in the 

 Red Sea and in the southeastern African regions), p. 14 (certain species are characteristic of the 

 oceanic fauna; absent from the American side of the Atlantic, and from the European side north 

 of the Bay of Biscay), p. 23 (distribution in the East Indies in detail), p. 59 (in key), p. 195 

 (original reference; genotype); Internat. Rev. gesamt. Hydrobiol. und Hydrogr., 1914, pp. 4 

 and following (occurs in both Atlantic and Indo-Pacific; range); Die Crinolden der Antarktis, 

 1915, p. Ill (synonymy; range), p. 181 (both Atlantic and Indo-Pacific; range in each) ; Unstalked 

 crinoids of the Si&oga-Exped., 1918, pp. 145, 147 (in key; range), p. 166 (key to the included 

 species); The Danish Ingolf-Exped., vol. 4, No. 5, Crinoidea, 1923, p. 40 (range; list of Atlantic 

 species). MORTENSEN, Handbook of the echinoderms of the British Isles, 1927, p. 25 (northeast 

 Atlantic species; in key). GISLEN, Vid. Medd. Dan'sk Naturh. Foren. K0benhavn, vol. 83, 

 1927, p. 6; Ark. Zool., vol. 19, No. 32, Feb. 20, 1928, p. 7. A. H. CLARK, Journ. Linn. Soc. (Zool.), 

 vol. 36. No. 249, April 1929, p. 651. GISL^N, Kungl. Fysiogr. Sallsk. Handl., new ser., vol. 45, 

 No. 11, 1934, pp. 18, 20. 



Diagnosis. A genus of Thalassometridae in which the arms are dorsally rounded 

 to the tips; the lower segments of the genital pinnules are not appreciabty expanded; 

 PI is much larger and stouter than P 2 , which resembles the pinnules following; the cirri 

 are recurved distally, the short outer segments bearing dorsal spines; the division series 



