208 BULLETIN 82, UNITED STATES NATIONAL MUSEUM 



modica and D. mobiusi and gave their catalog numbers. In my memoir on the 

 crinoids of the Indian Ocean published on November 22, 1912, I listed Decametra 

 modica, giving the synonymy and habitat. I also listed D. mobiusi, giving the speci- 

 man from Mauritius and also others from Muhlos, Maldives, and Fadiffolu, Mal- 

 dives, that I had examined at the British Museum in 1910. These had been included 

 under the name Antedon laevissima by Prof. F. Jeffrey Bell in 1902. In a paper on the 

 crinoids of the British Museum published in 1913 I listed one specimen of Decametra 

 moebiusi from Fadiffolu, Maldives, and three from Muhlos, Maldives, giving notes on 

 them. These were the specimens just mentioned. 



Dr. Robert Hartmeyer in 1916 corrected the catalog numbers on the specimens 

 of Decametra mobiusi and D. modica, in the Berlin Museum. 



In my report upon the unstalked crinoids of the Siboga expedition published in 

 1918 I included modica in the key to the species of the genus Decametra, and in a foot- 

 note gave D. mobiusi as a synonym of it. 



DECAMETRA sp. 



Cyllometra sp. A. H. CLARK, Zool. Anz., vol. 34, No. 11/12. 1909, p. 368. 

 Decametra sp. A. H. CLARK, Crinoids of the Indian Ocean, 1912, p. 164. 



Remarks. The German steamer Gazelle dredged in the southern Indian Ocean 

 (exact locality and depth not recorded) a small mutilated example of some species of 

 Decametra. 



Genus OLIGOMETRA A. H. Clark 



Antedon (part) P. H. CARPENTER, Notes Leyden Mus., vol. 3, 1881, p. 182, and following authors. 



Oligomelra A. H. CLARK, Proc. Biol. Soc. Washington, vol. 21, 1908, p. 126 (diagnosis; genotype 

 Antedon serripinna P. H. Carpenter, 1881), p. 135 (referred to the Himerometridae) ; Proc. 

 U. S. Nat. Mus., vol. 34, 1908, p. 211 (referred to the Himerometridae), p. 212 (occurs in West 

 Indies [Analcidomelra] and Japan) ; Proc. Biol. Soc. Washington, vol. 22, 1909, p. 7 (list of 

 included species) ; Amer. Nat., vol. 43, 1909, p. 254 (represented in Red Sea [refers to Deca- 

 metra]) ; Vid. Medd. Naturh. Foren. K0benhavn, 1909, p. 174 (included in the Colobometridae) ; 

 Proc. U. S. Nat. Mus., vol. 40, 1911, p. 6 (Antedon serripinna recorded by Chadwick from 

 Red Sea not an Oligomelra}, p. 13 (common to southeast Africa and Ceylon, but not found in 

 Arabian Sea); Die Fauna Siidwest-Australiens, vol. 3, Lief. 13, 1911, p. 439 (3 species peculiar 

 to Australia [including Oligometrides and Austrometra]) ; Mem. Australian Mus., vol. 4, 1911, 

 p. 725 (Australian species [including the species of Oligometrides and Austrometra]), pp. 730, 731 

 (in key), p. 734 (key to the Australian species), p. 775 (original reference; characters; range); 

 Rec. Indian Mus., vol. 7, pt. 3, No. 26, 1912, p. 267 (really Oligometrides). HARTLAUB, Mem. 

 Mus. Comp. Zool., vol. 27, No. 4, 1912, p. 371 (discussion). A. H. CLARK, Crinoids of the 

 Indian Ocean, 1912, p. 9 (in Australia distinctive local species [of Oligometrides and Austro- 

 metra, with 1 of Oligometra] replace the common East Indian forms), p. 11 (respresented in 

 Ceylon region; western limit of the large species is at Ceylon), p. 12 (represented in Red Sea 

 and southeast African regions), p. 22 (distribution in detail), p. 58 (in key), p. 168 (original 

 reference; genotype), p. 323 (discussion); Unstalked crinoids of the Siboga-Exped., 1918, 

 p. viii (discovery of intermediates between this genus and Decametra), p. Ill (in key), p. 113 

 (in key), p. 128 (key to the included species). GISLEN, Vid. Medd. Dansk Naturh. Foren., 

 vol. 83, 1927, pp. 27, 29; Kungl. Fysiogr. Sallsk. Handl., new ser., vol. 45, No. 11, 1934, p. 18. 

 EKMAN, Tiergeographie des Meeres, 1935, p. 283. H. L. CLARK, Echinoderm fauna of Aus- 

 tralia, 1946, p. 48 (in key), p. 49 (key to Australian species). 



Diagnosis. A genus of Colobometridae including small species with 10 arms 

 30-83 (usually 40-60) mm. long in which the rather stout cirri are composed of 13-28 



