366 



about 100 mm long; the II Br. series are 4 (3 + 4), the III Br. series 

 are about equally 2 and 4 (3 + 4), the IV Br. series are almost always 

 present, 4 (3 + 4), rarely 2; V Br series are common, and YI Br series 

 occur, all 4 (3 + 4). The centro-dorsal is irregularly rounded-penta- 

 gonal, countersunk to the level of the radiais, the periphery somewhat 

 notched with obsolete cirrus sockets. 



Dr. Carpenter indicated on the label that this specimen was »near 

 jjeroiii«, which species has been, and I believe correctly, placed in the 

 synonymy of bennetti by Dr. Hartlaub. Bnt peronii and bennetti are 

 remarkable for their massive centro-dorsals, numerous stout cirri, and 

 large lower pinnules, characters quite the reverse of those found in the 

 present example. 



In determining this specimen, we find that the rudimentary centro- 

 dorsal and the absence of cirri at once eliminate from consideration 

 Comanthus quadrata^ C. trichoptera, C. japonica^ C. grandiccdyx, C, 

 duplex, C. imbricata, C. robustipinna, C. regalis, C. schlegelii, C. so- 

 laster, C. serrata, and C.decameros; the very large number of arms distin- 

 guish it from C. rotalaria, C. intricata, and C. littoralis^ the absence of 

 strong dorsal processes on the joints of the lower pinnules from C. belli^ 

 and the separation of the rays from C. magnifica; passing over the 

 species in which the II Br are regularly 2, the possibilities narrow down 

 to C. polycnemis, C. altemans, C. briareus, C. divaricata and C. nobilis; 

 the similarity of the III Br series on each distichium eliminate C. nobilis, 

 and the IV Br and following series of 4 (3 + 4) show that it cannot be 

 C. polycnemis or C. altemans. It is, therefore, either C. briareus or C. 

 divaricata. Now Carpenter gives as the only difference between these 

 two that the former has »fifteen to twenty small cirri« , while the latter 

 has the > centro-dorsal stellate, without cirri« ; later he says of C. briareus 

 that its »centro-dorsal is evidently undergoing reduction to the Phano- 

 genia — like condition«. There appear to be no other differences and, 

 as the only distinguishing character given is one quite without value, 

 we are forced to consider the two nominal species as one, a course which 

 is the more justified in that the centro-dorsal of the present specimen 

 is exactly intermediate in its condition between that of the type of bri- 

 areus, and that of the type of divaricata. 



The disk of the present specimen is lost, but it was evidently very 

 large for the size of the arms and pinnules, as noticed by Carpenter 

 in C. divaricata. 



The colour is light brownish, as in numerous specimens at hand 

 from the Philippine Islands. 



