PART 5 A MONOGRAPH OF THE EXISTING CRIKOIDS 763 



long. 129°06' E.); 660 meters; temperature 5.95° C; gray sand, globigerinac and 

 broken shells; August 13, 1906 [A. H. Clark, 1907] (1, U.S.N.M., 22617). Type locality. 



Albatross station 4916; Eastern Sea, about 90 miles WSW. of Kagosiiima Gulf; 

 Gwaja Shima bearing S. 37° E., 37.5 miles distant Oat. 30°25' N., long. 129°06'40" 

 E.); 660 meters; temperature 5.95° C; globigerinae and broken shells; August 13, 

 1906 (2, U.S.N.M., 35926). 



?Korea; Capt. Suensson, 1S93 [A. H. Clark, 1909] (1, CM.). 



Albatross station 4971; Linschoten Strait, between Shikoku and Honshu; Shio 

 Misaki Light bearing N. 75° E., 9.6 miles distant (lat. 33°23'30" N., long. 135°34'00" 

 E.); 1186 meters; temperature 3.39° C. ; brown and green mud and foraminifera; 

 August 30, 1906 (1, U.S.N.M., 36080). 



Geographical range. — Southwestern Japan from southwest of Kyushu to the 

 Linschoten Strait (? Korea). 



Bathymetrical range. — From 660 to 1186 meters. 



Thermal range.— From 3.39° C. to 5.95° C. 



Remarks [by A.M.C.]. — The only specimen of T. isis which has been described has 

 the arms 65 mm. long, so that a direct comparison with the sympatric species parva is 

 difficult. The largest specimen of the latter, that from Sagami Bay in 731 meters 

 named comaster by Gislen in 1922, has the arms 45 to 50 mm. long, the longest of the 

 15 cirrus segments is about three times as long as broad. The smaller specimens of 

 parva have progressively fewer and relatively longer cirrus segments, so that it is 

 likely that one with arms as much as 65 mm. long would have the longest cirrus seg- 

 ments less than three times as long as wide, as they are in isis. In 1927 Gisl6n figured 

 the base of a cirrus of the specimen from ?Korea named isis by Mr. Clark in 1909. 

 This appears to have the cirrus segments relatively longer than in the type of isis and 

 much more like those of parva. 



It may be that the position of the first genital pinnule, P2 in parva as opposed to 

 Pi in isis, is more reliable in distinguishing the two species. But Gislen has also 

 described a specimen under the name Thaumatometra cf. tenuis from 110 meters in 

 Sagami Bay with arm length 40 mm. in which either P3 or P4 is the first genital pinnule. 

 The gonads of this specimen were small and he concluded that it was immature and 

 therefore could not be conspecific with the specimen he had named comaster in 1922 

 (.i.e. parva) or with isis. With the present inadequate material of these species no 

 definite conclusion can be reached about this specimen. It is described more fully 

 under the heading of tenuis. 



THAUMATOMETRA COMASTER A. H. Cl«rk 



Thaumatometra comaster A. H. Clark, Proc. Biol. Soc. Washington, vol. 21, 1908, p. 128 O'sted; 

 nomen nudum); Proc. U.S. Nat. Mus., vol. 34, 1908, p. 232 (description; Albatross sta. 5032); 

 Crinoids of the Indian Ocean, 1912, p. 246 (synonymy; locality); Journ. Washington Acad. Sci., 

 vol. 5, 1915, \o. 6, p. 215 (locality; range and its significance) ; Unstalked crinoids of the Siboga- 

 Exped., 1918, p. 255 (in key; range), p. 2.56 (references). (Not T. comaster Gislen, 1922, 1924, 

 and 1927= r. parva A. H. Clark.) 



Diagnostic features. — The centrodorsal is much flattened, almost discoidal; the 

 XL to XLV cirri are composed of 13 to 17 segments, of which the longest are three 

 times as long as broad and the last 3 or 4 are not very much longer than broad ; Pj is 

 the first genital pinnule. When the arms are 45 mm. long the cirri are only about 8 mm. 



550-621—67 SO 



