364 BULLETIN 82, UNITED STATES NATIONAL MUSEUM 



The cirri, 20 mm. long, are composed of the same number of segments as are 

 those of A'', multicolor. In A^". multicolor the segments in the distal half of the cirri are 

 rounded ventrally, their distal ends on the ventral side are even with the proximal 

 ends of the succeeding segments, the width is about twice the length in the middle 

 lateral line, and the dorsal spines arise from one-half or rather less of the dorsal sur- 

 face and are small and pointed. In A'', acanthaster the distal half of the cirri is sharply 

 carinate ventrally, the distal ends of the segments are prominent, overlapping the 

 bases of the succeeding segments, the segments themselves are broader, being about 

 3 times as broad as long in the lateral line, and the dorsal spines, which arise from the 

 entire dorsal surface of the segments are high and terminate in a long ridge parallel to 

 the longitudinal axis of the cirri instead of in a point. 



The arms, 60 mm. long, are 30 in number instead of 20 or less as in A^. multicolor, 

 IIIBr 2 series being developed on the outer side of each IIBr series m 2, 1, 1,2 order. 



Pa is as large as and resembles Pa instead of being considerably smaller as is 

 usually the case in A'', multicolor. 



Locality. — Albatross station 5153; Philippine Islands; Sulu (Jol6) Archipelago, 

 Tawi Tawi group; Tocanhi Point bearing S. 27° E., 2.1 miles distant (lat. 5°]8'10" N., 

 long. 120°02'55" E.); 89 meters; coral sand and shells; February 19, 1908 [A. H. Clark, 

 1908] (6, U. S. N. M., 25446, 355G0). 



Remarks. — Only the six original specimens of this species are known. 



NEOMETRA SPINOSISSIMA (A. H. Clark) 



Plate 39, Figure 203 

 (See also vol. 1, pt. 2, figs. 506, 507 (pinnule tip), p. 276; fig. 761 (side- and covering-plates), p. 353.] 



Calometra spinosissirna A. H. Clark, Proc. Biol. Soc. Washington, vol. 22, 1909, p. 79 (description 

 Andaman Islands). 



Calometra spinossima A. H. Clark, Proc. U. S. Nat. Mus., vol. 39, 1911, p. 544 (affinities; cirri 

 compared with those of C. alecto). 



Neometra spinosissima A. H. Clark, Crinoids of the Indian Ocean, 1912, p. 181 (synonymy; detailed 

 description; Andaman Is.), fig. 30, p. 182; Rec. Western Austrahan Mus., vol. 1, pt. 3, 1914, 

 p. 128 (affinities), p. 130 (characters; range); Unstalked crinoids of the Siboga-Exped., 1918, 

 p. 133 (in key; range). — Gisl^n, Nova Acta Reg. Soc. Sci. Upsahensis, ser. 4, vol. 5, No. 6, 

 1922, p. 96 (characters of the lower pinnules); Kungl. Fysiogr. SaUsk. Handl., new ser., vol. 45, 

 No. 11, 1934, p. 20. 



Diagnostic features. — This is the largest species in the genus, the arms being 

 130 mm. in length; the cirri are slender and short, reaching less than one-fifth of the 

 length of the arms, with 42-55 segments; and there are 20 arms. 



Description.- — The centrodorsal is discoidal, moderately thick, with the bare 

 polar area flat and 3 mm. in diameter. The cirrus sockets are arranged in a single 

 crowded marginal row. 



The cirri are XI, 42-55, 25 mm. long, moderately slender. The first segment is 

 about thi-ee times as broad as long, and those following slowly increase in length to 

 the sixth or seventh, which is nearly as long as broad. The succeeding segments 

 are similar to the twelfth or fifteenth, from that point onward gradually decreasing 

 in length so that the segments in the terminal portion are twice as broad as long. At 

 about the fifteenth a low sharp dorsal keel makes its appearance, at first in the distal 

 portion only but soon along the entire dorsal surface, which very slowly increases 



