102 Papers from the Department of Marine Biology. 



to almost uniformly dead black, with bewildering diversity. One form is so 

 sharply set off from the others that it is entitled to designation by varietal 

 name and may be called var. xanthum. In it the dorsal surface is deep canary- 

 yellow, while the pinnules are bright red. Only three specimens were found, 

 all near the edge of the reef. Except for color, the specimens are not peculiar. 

 Unfortunately the colors are very fugitive in alcohol. 



10. Comanthus callipeplum sp. nov. (<caXXi7rirXoj = beautifully robed). 

 Centrodorsal moderate, flat, 5 mm. in diameter. Cirri vm, 15, about 



7 mm. long. In addition to these rudimentary cirri, the margin of the centro- 

 dorsal has 10 large cirrus sockets. The small cirri taper to a slender tip. 



I Br and II Br series in close contact with the adjoining series of the same 

 rank on either side, their dorsal surface smooth and nearly flat. Arms 78, 

 about 90 mm. long and with approximately 100 brachials. II Br series 

 usually 4 (3+4), but occasionally only 2. Ill Br series generally 2, but in one 

 arm 3 and in two arms 4 (3+4). IV Br series 4 (3+4), except one arm which 

 has 2. V Br series 4 (3+4). Syzygies between brachials 3 and 4, and 8 

 and 9, and then at intervals of three or four brachials. Outer brachials 

 more or less overlapping with finely serrate distal margins. Lower pinnules 

 on brachials rather short with 14 to 16 segments; distal pinnules notably longer 

 and more slender, but with the same number of segments. Oral pinnules 

 with 35 to 40 joints, but only the terminal fifth make up the comb. General 

 color, dorsally dark green, with joints and some small spots greenish-yellow; 

 sides of arms, including pinnules (and distally much of their dorsal surface), 

 yellowish- white; centro-dorsal, partly white; cirri, yellow; tips of pinnules, usu- 

 ally rusty-red. Oral surface, very dark, but finely mottled with yellow-green. 

 Colors little altered by preservation in alcohol. 



This superb comatulid was found among madrepore corals near the outer 

 edge of the southwest reef-flat at Maer. Only a single specimen was seen. 

 Although nearly related to C. briareus (Bell), it is distinguishable by the 

 presence of cirri, the great breadth of the II Br series, the absence of interradial 

 plating, the frequent syzygies, and the remarkable coloration. The specimen 

 was kept alive in the laboratory for nearly 24 hours, while a colored figure 

 was being made, but it died and broke to pieces before preservation and is 

 now in an unfortunately fragmentary condition. 



11. Comanthus luteofuscum sp. nov. (luteofuscus = yellow-brown). 

 Centro-dorsal small (2 mm. in diameter of bare surface), thick, flat, or & 



trifle concave. Cirri xvm-xxii, 13-17, rather short, about 10 mm. long. 

 Except segments 4-7 (from the base), the cirrus-segments are short, wider 

 than long; except 7 or 8 basal segments, each segment has a dorsal elevation 

 of more or less prominence ; this may be a tubercle, a spine, or a rough trans- 

 verse ridge; it is often conspicuous. I Br series 3 (2+3); I Br t in close 

 opposition with its adjoining fellows; I Br 2 notably wider than I Br 3 and in 

 broad contact with its fellows; I Brs almost triangular, very low and broad, 

 well separated from its fellow on either side. Arms 20 to 30, notably short, 

 50 to 60 mm. long, usually approximately equal but sometimes distinctly longer 

 on one side of the animal than on the other; each arm is made up of 80 to 100 

 brachials, which, except at tip of arm, are low, more or less discoidal, and have 

 everted and finely serrate distal margins, particularly near middle of the arm. 



II Br series generally 4 (3+4), but occasionally 2. II Br a in close contact 

 with its fellow of the same ray. Ill Br series generally 4 (3+4), but some- 

 times 2. Ill Brj in contact with its fellow of the same half-ray. First 

 brachials in similar contact. Syzygies between brachials 3 and 4, and 10-11 

 or 11-12; after that at intervals of 3 to 5 segments. Oral pinnules with 30 



