658 BULLETIN 82, UNITED STATES NATIONAL MUSEUM 



The specimen from the reef at Siboga station 131 has 21 arms 100 mm. long. 

 The 10 IIBr and the single IIIBr series present are 4 (3 + 4). 



The specimen from Siboga station 131 in 13 meters has 20 arms about 90 mm. 

 long. Of the 10 IIBr series 6 are 4 (3 + 4) and 4 are 2. There arc III cirri. 



Of the 2 specimens from Siboga station 133, 1 has 28 arms, and the other has 12 

 arms 50 mm. long. 



Two of the Challenger specimens from Zamboanga were described by Carpenter 

 under the name of Actinometra rotalaria as follows: 



The centrodorsal is a small thin disk. 



The cirri are about X, 10-12. None of the segments are much longer than broad. 



The radials are just visible beyond the rim of the centrodorsal. The IBri are 

 closely united laterally. The IIBr series are 2. The IIIBr series are 4 (3+4). 



The 20-30 arms are 40 mm. in length and consists of about 80 subtriangular and 

 overlapping brachials. Some of the posterior arms may be ungrooved. 



Syzygies occur between brachials 3+4, 11 + 12, and 16+ 17, and distally at inter- 

 vals of 4 or 5 muscular articulations. 



The IIIBr2, when present, has a moderately long pinnule with rather stout 

 lower segments. Pi is nearly as long, but Pa is much smaller. P2 and Pj are also 

 small, but the succeeding pinnules increase considerably in both length and stout- 

 ness. The terminal comb is rather small and does not extend beyond the pinnule of 

 the seventh brachial. 



The disk is 6.5 mm. in diameter and is naked. The mouth is apparently radial. 



The color in alcohol is light brownish white. 



Carpenter noted that the cirri are arranged in 5 radial pairs which are placed 

 interradially, or nearly so. He mentioned the similar arrangement in Comatula 

 purpurea, but overlooked the fact that he had also described it in variety 2 of Acti- 

 nometra polymorpha. 



The figure is not entirely in accord with the description. It shows a much 

 broken individual with 23+ arms. Of the 9 IIBr series, 6 are 2 and 3 are 4 (3 + 4). 

 Of the 4 IIIBr series, 3 are 4 (3+4) and 1 is 2. He said, however, under "Remarks," 

 that IIBr 4 (3 + 4) series occur abnormally in both his specimens, while sometimes 

 the IIIBr series are 2 instead of 4 (3 + 4). 



Of the 7 specimens from Zamboanga that he identified as parvicirra Carpenter 

 said that 1 or 2 appear to approach Actinometra quadrata, and it may be that the latter 

 name will have to be abandoned. In at least 6 of the 7 the arms are dimorphic. 

 Spherodes occur in one of the specimens. In another there is a relatively large 

 number of small and rudimentary cirri on a very thin centrodorsal. I have examined 

 4 of these specimens, with 33, 32, 22, and 14 arms. In the last there are V well-de- 

 veloped cirri which are interradial in position; in the others the cirri are much reduced 

 or rudimentary. 



Dr. Th. Mortensen's specimen from Santa Cruz Island, Zamboanga, has 20 

 slender arms, of which the anterior are 100 mm. and the posterior are 60 mm. in length. 

 There are 10 IIBr 4 (3 + 4) series. The cirri are VII, 14-15. There is an unusual 

 development of small spines on the brachials and pinnulars, so that the specimen 

 feels more like an example of Comanthus samoana than like one of C. parvicirra. 



