154 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. xxxiii. 



gated, the others shorter than broad, the distal bearing low spines. 

 The cirri are moderately stout, resembling those of O. jajponica. 



Kadials usually concealed as far as the axillary. Axillaries trian- 

 gular, over twice as broad as long. Distichals and palmars 4 (3 + 4), in 

 close apposition, and flattened, as in the Basicurva group of Antedon. 

 In some places the distichals are separated enough to make room for 

 the dorsal keel of the much flattened distichal pinnule, but the perisome 

 is never visible from the dorsal surface. Twenty to 80 arms, very 

 stout, tapering rather rapidly, the brachials quadrate, very short, and 

 strongly overlapping. Lower pinnules not especially large, but 

 greatly compressed and very strongly carinate for the basal 8 to 12 

 joints. This carination decreases in degree after the first 3 or 4 pairs 

 of pinnules, but is evident even on the distal pinnules. The pinnules 

 (except for the first few pairs) have their joints overlapping and 

 finely spinous. 



Color in life dark purple, the disk, cirri, and pimuiles brownish 

 yellow. 



Tyjje.—Q^ii. No. 22656, U.S.N.M.; from AJhatross station No. 4944; 

 31° 38' 15" north latitude, 130° 46' 50" east longitude (in Kagoshima 

 Gulf); 43 fathoms; August 17, 1906. 



This species is readily distinguished by its very massive radials and 

 distichals, which form a solid cup, so that none of the perisome is per- 

 ceptible from the dorsal side; very small specimens show that this 

 character is assumed at an early period of gi"owth. In the adults the 

 radials and distichals are so closely welded together that it becomes 

 difficult to trace the sutures. 



33. COMATULA SERRATA, new species 



Centro-dorsal a thick, flat, pentagonal disk with about 15 marginal 

 cirri in two irregular rows; the cirri are small, with 10 joints, the 

 third and fourth much elongated, becoming rapidly shorter distally. 

 The terminal 7 joints bear small dorsal spines, that on the penul- 

 timate being the largest; terminal claw rather long. 



First and most of the second radials concealed; two outer radials 

 united by sj'zygy; distichals 4 (3+4); rarely 2(1 + 2); rays separated 

 from the second radial; first brachials closely united interiorly, the 

 second brachials free; first two brachials united by S3 zygy. First three 

 brachials oblong, then quadrate, becoming triangular, about as wide as 

 long after the seventh; the radials, distichals, palmars, and brachials 

 all have everted and serrate edges; in the only arm remaining the 

 ninth, twelfth, fifteenth, eighteenth, and twenty-first brachials are 

 syzygies. The pinnule joints have strongly spinous distal edges. 



Color in life dull greenish. yellow. 



