580 BULLETIN 82, UNITED STATES NATIONAL MUSEUM 



Beyond the second brachial the arms bear a narrow interrupted dark purple 

 dorsal stripe that extends nearly their entire length. 



Locality. Albatross station 4930; in Colnett or Vincennes Strait; northeastern 

 point of Yaku Shima bearing N. 19 W., 10.7 miles distant (lat. 3012'00" N., long. 

 13044'00" E.); 153 meters; broken shells, coral, and pebbles; bottom temperature 

 23.78 C.; August 15, 1906 [A. H. Clark, 1907, 1908, 1912, 1913, 1915, 1918] (1, 

 U.S.N.M., 22646). 



History. This species was described by me as Antedon delicatissima on September 

 17, 1907, from a specimen dredged by the Albatross in 1906 at station 4930. 



In my first revision of the old genus Antedon, published on October 29, 1907, 

 delicatissima was assigned to the new genus Himerometra. It was not mentioned in 

 my revision of the family Himerometriclae published in 1909. 



In a paper on new crinoids belonging to the families Himerometridae, Mari- 

 ametridae, and Colobometridae collected by the Siboga in the Dutch East Indies 

 published hi July 1912, the new species Mariametra tuberculata was said to be nearest 

 M. delicatissima. 



In my memoir on the crinoids of the Indian Ocean published on November 

 22, 1912, I listed Dichrometra delicatissima and gave the synonymy and locality. 



In my memoir on the unstalked crinoids of the Siboga expedition published in 

 1918 delicatissima was included in the key to the species of Mariametra, and the range 

 was given. 



MARIAMETRA TUBERCULATA A. H. Clark 



PLATE 61, FIGURE 281 

 [See also vol. 1, pt. 2, fig. 196 (lateral view), p. 124.] 



Mariamelra tuberculata A. H. CLARK, Ann. Mag. Nat. Hist., ser. 8, vol. 10, 1912, p. 33 (description; 

 Siboga station 51) ; Proc. Biol. Soc. Washington, vol. 26, 1913, p. 144 (listed) ; Unstalked crinoids 

 of the Siboga-Exped., 1918, p. 108 (in key; range; detailed description; station 51), p. 271 

 (listed), pi. 20, fig. 44 GISLEN, Kungl. Fysiogr. Sallsk. Handl., new ser., vol. 45, No. 11, 

 1934, p. 25. 



Diagnostic features. The arms are about 30 in number, 75 mm. long; there is a 

 faint median dorsal line of pinkish 011 the proximal half of the arms, but none on the 

 division series; the sides of the ossicles of the division series are coarsely tubercular; 

 the cirri, which are about one-quarter the length of the arms, have less than 30 seg- 

 ments, of which the longest are twice as long as broad and the last four or five are 

 from about as long as broad to one-third again as long as broad; the last 11 or 12 

 cirrus segments have a slight distal dorsal carination; P 3 is 12 mm. long, with 16-18 

 segments, half again as long as P 2 . 



Description. The centrodorsal is large, thick discoidal, with the dorsal pole 

 slightly convex, 2 mm. in diameter. The cirrus sockets are arranged in two closely 

 crowded and irregular alternating rows. 



The cirri are XXI, 25-27, 20 mm. long, and rather slender, with a slight distal 

 taper. The first segment is short, the second is longer, the third is nearly as long as 

 broad, the fourth is slightly longer than broad, and the sixth and following are twice 

 as long as broad. The segments following the tenth slowly decrease in length so that 

 the last four or five before the penultimate are from about as long as broad to 

 one-third again as long as broad. The last 11 or 12 segments have a slight distal 

 dorsal carination, which is low and rises very gradually from the dorsal surface of the 



