A MONOGRAPH OF THE EXISTING CRINOIDS 237 



In the specimens from the Ganjam coast of India the lower pinnules are strongly 

 serrate. 



Localities. — ?Tranquebar, just north of Karikal, southeastern India [A. H. 

 Clark, 1908, 1909, 1912, 1918] (2, C. M.). 



Bengal Fisheries steamer Golden Crown; Ganjam coast, Madras Presidency; 

 44-55 meters [A. H. Clark, 1912] (2, U.S.N.M., 35339; I. M.). 



?Iudia (probably Ceylon) [A. H. Clark, 1912] (1, I. M.). 



Geographical range. — Eastern coast of India. 



Bathymetrical range. — From the shore hne down to 44 (?55) meters. 



History. — This variety was originally described by me in 1908 as Oligometra 

 imbricata from two specimens in the Copenhagen Museum from ?Tranquebar that 

 had been labeled Antedon cupuliferus var. by Prof. C. F. Liitken. In a paper on the 

 crinoids of the Copenhagen Museum published in 1909 I said that Dr. Clemens 

 Hartlaub had identified as Oligometra serripinna specimens of Liitken's Antedon 

 cupuliferus that I had found in the Hamburg Museum (see under Oligometra cale- 

 doniae, p. 241), so that I had thought it best not to use Liitken's name as the specific 

 designation of this form as it might cause confusion. In my memoir on the crinoids 

 of the Indian Ocean published in 1912 I figured a typical specimen of 0. imbricata 

 and recorded two specimens from the Ganjam coast of Indian in 24-30 fathoms, and 

 one from ?India. In the key to the species of Oligometra published in my report on 

 the unstalked crinoids of the Siboga expedition in 1918, I included imbricata, giving 

 as the locahty ?Tranquebar, India. 



OUGOMETBA SERRIPINNA var. ERINACEA A. H. Clark 



Fulte 28, Figures 148, 149 



Oligometra serripinna var. erinacea A. H. Clark, Crinoids of the Indian Ocean, 1912, p. 323 (1 

 specimen in the type series laclis P, on both arms of 1 ray), p. 324 (detailed description and 

 comparisons; locality). 



Oligometra erinacea A. H. Clark, Unstalked crinoids of the Sihoga-Expcd., 1918, p. 129 (in key; 

 range) . 



Diagnostic jeatures. — The distal edges of the brachials in the proximal third of 

 the arm are turned abruptly outward and greatly produced, with a scalloped and ir- 

 regular crest; proximal to the second syzygy this e version becomes restricted to the 

 central portion of the distal edge and may be more or less resolved into high tubercles 

 or blunt spines; the anterior angle of the axiUary is usually produced dorsalward or 

 bears tliree prominent tubercles; the lateral processes of the segments of Pj are high 

 and broad, usually with a truncated distal angle. 



Description. — The centrodorsal resembles that of 0. serripinna. It is thin 

 discoidal, 2 mm. in diameter, with the dorsal pole flat, usually with a raised rim. 



The cirri are XV-XVII, 21-24 (usually 23), from 10 to 12 mm. long. They are a 

 trifle more slender than the cirri of 0. serripinna, and usually have a slight, though 

 perceptible, distal taper after the proximal half. The segments are all short, most of 

 them about half again as broad as long, not becoming as long as broad until the second 

 or third before the penultimate. The dorsal processes resemble those of the cirri of 

 0. serripinna, but the transverse ridge toward the middle of the cirri shows a more or 

 less marked division into two halves accompanied by a more or less deep and angular 



