244 BULLETIN 82, UNITED STATES NATIONAL MUSEUM 



his material with the type of Carpenter's Antedon serripinna, and with his new A. 

 japonica (=Iconometra japonica). 



In my paper on the crinoids of the Copenhagen Museum published in 1909, I 

 included Antedon cupulifera in the synonymy of Oligometra serripinna. In a paper 

 on the crinoids of the Paris Museum published in 1911 I described Oligometra cale- 

 doniae on the basis of a single specimen that had been collected in New Caledonia 

 by M. Vigue in 1875. In a paper on the crinoids of the Hamburg Museum published 

 in 1912, I redescribed 7 of the specimens from the Tonga Islands that had been 

 discussed by Hartlaub in 1891, and compared them with 0. occidenralis, 0. serripinna, 

 and 0. japonica. In my memoir on the crinoids of the Indian Ocean published later 

 in 1912, I included Antedon cupulifera in the synonymy of Oligometra serripinna, and 

 gave the Tonga Islands as among the localities for the latter. In a paper on the 

 crinoids of the British Museum published in 1913 I recorded a specimen of Oligometra 

 caledoniae without locality that had been collected by Prof. J. Beete Jukes. In my 

 memoir on the unstalked crinoids of the Siboga expedition published in 1918, I in- 

 cluded caledoniae in the key to the species of the genus Oligometra, giving as the 

 range New Caledonia and the Tonga Islands. This is the only intimation that the 

 specimens from these two localities were considered conspecific. 



OLIGOMETRA SERRIPINNA CHINENSIS A. H. Clark 



PLATE 27, FIGURE 144; PLATE 28, FIGURE 152 



Oligometra serripinna A. H. CLARK, Smithsonian Misc. Coll., vol. 60, No. 10, 1912, p. 27 (in part; 



Fuchow; characters); Proc. Biol. Soc. Washington, vol. 26, 1913, p. 179 (Fuchow). 

 Oligometra chinensis A. H. CLARK, Unstalked crinoids of the Siboga-Exped., 1918, p. 130 (in key; 



range). GISLBN, Zool. Bidrag Uppsala, vol. 9, 1924, p. 283. G. A. SMITH, Ann. Mag. Nat. 



Hist., ser. 9, vol. 20, No. 117, 1927, p. 272 (Fukien). GISLEN, Vid. Medd. Dansk Naturh. 



Foren., vol. 83, 1927, p. 29 (comparison with Prometra [Decametra] perplexa). 



Diagnostic features. P 2 is not greatly enlarged, becoming delicate distally, 

 with the distal segments twice as long as broad or even longer, the profile serrate 

 in the distal half; the second-fourth segments of the lower pinnules are narrowly 

 carinate; the cirri are relatively long and slender with up to 24 segments. 



Description. The centrodorsal is thin discoidal with a flat dorsal pole having 

 a somewhat irregular surface. The cirri are arranged in two closely crowded alter- 

 nating marginal rows. 



The cirri are XXIII, 20-21, up to 8 mm. long. In the fully developed periph- 

 eral cirri the First four segments are very short, about four times as broad as long, 

 and those following slowly increase hi length so that the outermost are usually about 

 as long as broad, though they vary from slightly broader than long to slightly longer 

 than broad. The ventral surface of the cirri is rather abruptly arched in the proxi- 

 mal portion, becoming more regularly arched in the distal half. Ventrally the 

 distal ends of the segments are slightly produced, this being especially noticeable in 

 the proximal third of the cirri and diminishing distally, finally almost or quite dis- 

 appearing. Viewed dorsally the cirri are seen to taper more rapidly hi the proximal 

 third than distally, and the dorsal surface in the earlier broadened portion is strongly 

 flattened. Dorsally the distal ends of the third or fourth and following segments 

 are produced, this production after the proximal third moving slowly proximally 

 and becoming an arcuate finely spir ous transverse ridge. Moving still further proxi- 



