654 BULLETIN 82, UNITED STATES NATIONAL MUSEUM 



compression, which is not visible until the eighth segment, becomes somewhat 

 marked toward the end of the cirrus, which is more distinctly flattened than in the 

 type, although the small spines on the distal dorsal margins do not appear at all 

 until the 3 or 4 last segments, and even on these they are but slightly developed. 



Carpenter said, further, that the 10 IIBr series are all 4 (3 + 4). 



The position of the first 3 brachial syzygies varies as follows: Between brachials 

 3 + 4, 11 + 12, 15 + 16 (once); brachials 3 +4, 11 + 12, 16+17 (10 times); 3 + 4, 11 + 12, 

 19 + 20 (3 times); 3 + 4, 12 + 13, 17 + 18 (4 times); 3 + 4, 13 + 14, 18+19 (once); 

 3 + 4, 15 + 16, 20 + 21 (once). 



The number of muscular articulations in the first intersyzygial interval varies 

 as follows: 7 (14 times); 8 (4 times); 9 (once); 11 (once). 



The number of muscular articulations in the second intersyzygial interval varies 

 as follows: 3 (once); 4 (16 times); 7 (3 times). 



In the distal intersyzygial intervals the tendency is toward an increase in the 

 number of muscular articulations over the normal, as in variety 2. 



Carpenter said that, although this specimen is considerably smaller than the 

 type series and the single specimen representing variety 2, he believed it to be full 

 grown, for it has very large and well-developed gonads, while in a young and small 

 specimen in the type series of about the same size the genital glands are scarcely 

 developed at all. 



Carpenter thus described Actinometra polymorpha, which was based upon 8 

 specimens from Bohol, and also 4 additional specimens, each of which was described 

 as a distinct variety. 



The centrodorsal is a circular or irregularly pentagonal disk with the surface 

 flattened and slightly concave in the center which almost completely conceals the 

 radials. 



The cirri are marginal, XIV-XXV, 11-14 (usually 12-13). The fifth and sixth 

 segments are the longest. The basal segments are thick and broader than long. 

 The remainder taper gradually, and the terminal ones are laterally compressed. The 

 last 5 or 6 segments have a small dorsal spine, increasing in distinctness up to the 

 penultimate segment, which bears the terminal claw. 



The radials are barely visible. The IBr[ are short, in the mid-dorsal line of the 

 same length as the radials but somewhat shorter laterally. They are laterally united 

 for nearly their whole length. The IBr 2 (axillaries) are pentagonal, about twice as 

 long as the IBr^ The IIBr and IIIBr series are 4 (3 + 4). 



The arms are 13-40 in number and about 100 or 110 mm. in length. The first 

 segments following each axillary are in contact interiorly for nearly their whole 

 length. 



The first syzygy is between brachials 3 + 4, the next is 7 muscular articulations 

 beyond, and the distal intersyzygial interval is from 1 to 7, but usually 4, muscular 

 articulations. 



The anterior arms are much longer than the posterior, which latter are usually 

 without ambulacral grooves. The width of the arms increases from the fourth to the 

 twelfth brachial, remains uniform until about the sixteenth, and then decreases, 

 slowly in the long anterior arms and rapidly in the short posterior ones. The brachials 

 are wedge-shaped, slightly overlapping, with the distal edges fringed with short spines. 



