146 BULLETIN 82, UNITED STATES NATIONAL MUSEUM VOLUME 1 



cirri end in a sharp point without an opposing spine; P 2 is less than half as long as PI 

 but similar to P 3 . 



Description. Centrodorsal flattened hemispherical, the dorsal pole more or less 

 thickly covered with rounded tubercles, which become smaller centrally; cirrus sockets 

 arranged in one or two irregular crowded rows. 



Cirri X-XX, 12-17, from 7 to 11 mm. long, extremely slender, very slightly curved, 

 and tapering gradually to a sharp point in the distal fourth, composed of extremely long 

 segments with greatly swollen articulations, especially in the proximal portion; first 

 segment very short, second nearly as long as broad, third from two and a half to three 

 times as long as the diameter of the expanded distal end, and the following about 

 four times as long as the diameter of the greatly expanded distal ends, or over six 

 times the median width (see fig. 9,a, p. 149) ; beyond the fifth to eighth the expansion 

 of the distal ends of the segments gradually decreases, and the lateral diameter of the 

 segments after the tenth gradually decreases to the sharp tip; no opposing spine; 

 terminal claw very slender, and straight. 



Distal edge of the radials even with the rim of the centrodorsal, sometimes bearing 

 a few tubercles toward the interradial angles of the calyx; distal interradial angles 

 slightly separated. 



IBri very short, about four times as broad as long, twice as long laterally as in 

 the median line; lateral edges parallel or slightly converging, making an angle of about 

 90 with the lateral edges of the adjacent IBr 1; and not in contact basally; proximal 

 and distal edges broadly thickened, the proximal more broadly than the distal, and 

 very finely spinous; as a result of this thickening of the proximal and distal edges the 

 lateral borders have a rounded notch; IBr 2 (axillaries) rhombic, all the sides moderately 

 concave, with truncated lateral angles, from half again to twice as broad as long; 

 the lateral angles are slightly produced outward and downward in rounded latero- 

 posterior processes; the truncated ends of the lateral angles are about as long as the 

 median length of the IBri ; all the borders are slightly everted and very finely spinous. 



Arms 10, up to 40 mm. long, and exceedingly slender; brachials elongate, slightly 

 constricted centrally, this condition increasing distally, then' surfaces practically smooth, 

 with no production of the distal edges. 



Syzygies occur between brachials 3+4, 9+10, and 14+15, and distally at intervals 

 of 3 oblique muscular articulations. The arm width at the first syzygy is 0.7 mm. and 

 the length from the proximal edge of the IBr] to the second syzygy is 4.5 mm. 



P! is from 3.5 to 4.0 mm. long, tapering evenly from the base to the tip, composed 

 of from 9 to 11 segments, of which the first is twice as broad as long, the second half 

 again as long as broad, the third twice as long as broad, and the remainder from two 

 and a half to three times as long as broad; third and following with produced and over- 

 lapping spinous distal edges which are most developed along the distal side. P 2 is from 

 1.5 to 1.7 mm. long, much smaller and more slender than PI though with similar seg- 

 ments, of which the first is short, the second slightly longer than broad, the third twice 

 as long as broad, and the remainder elongated. P 3 is similar to P 2 , but very slightly 

 smaller, with only a very slight production of the distal dorsal edges of the segments. 

 The distal pinnules are from 2 to 4 mm. long, and extremely slender. 



Localities. Siboga station 50; Bay of Badjo, western coast of Flores; reef; April 

 16-18, 1899 [A. H. Clark, 1912, 1918] (14, Amsterdam M.). 



