334 BULLETIN 82, UNITED STATES NATIONAL MUSEUM 



HETEROMETRA DELAGOAE Gisln 



Heterometra africana var. delagoae GISLN, Kungl. Svenska Vet. Akad. Handl., ser. 3, vol. 17, No. 2, 

 1938, p. 4 (listed), p. 5 (characters), p. 10 (descriptions of specimens; Pieter Faure stations 

 1987, 2001, 2012, 2079, vicinity of Delagoa Bay), text figs. 8-11, p. 13, pi. 1, fig. 3. 



Diagnostic features. IIIBr series are present, usually 2 ; the brachials are very 

 short, those beyond the proximal fourth pjf the arms being discoidal with parallel 

 ends, and those in the proximal portion of the arms being unmodified. The cirri are 

 moderately stout and moderately curved in the outer portion and are composed of 

 about 30 segments, all of which are markedly broader than long. The 19-39 (most 

 commonly about 30) arms are 75-85 mm. long. 



Description. The centrodorsal is flat, 4.5 mm. in diameter; the cirrus sockets 

 are arranged in ft. partially double row. 



The cirri are XXI-XXXII, 25-34 (usually about 30), 12 to 24 (usually about 20) 

 mm. long. The longest proximal segments are one-third to one-half again as broad 

 as long, and the distal segments are twice as broad as long. The distal segments are 

 provided with long and sharp dorsal spines that begin abruptly on from the thirteenth 

 to the sixteenth segment. 



The IIBr series are usually 4 (3+4), sometimes 2, and the IIIBr series are usually 

 2, occasionally 4 (3 + 4), mostly internally developed. 



The arms are 19-39 (most commonly about 30) in number, from 75 to 85 mm. long. 



The first syzygy is between brachials 3 + 4, the second sometimes between brachials 

 5 + 6, or between brachials 9 + 10, and the third at about brachials 15 + 16. The distal 

 intersyzygial interval is from 7 to 10 muscular articulations. 



P D is 7.5 mm. long, with 21 segments. P[ is 9.5 mm. long, with 22 segments. 

 P 2 is 12 mm. long, with about 24 segments. P 3 is of about the same length as P 2 but 

 has fewer segments; on another specimen it is about 10 mm. long, with 20 segments. 

 P 4 is shorter than P 3 . The proximal pinnules are rather smooth, but angular hi cross 

 section, the proximal segments with a low double longitudinal carination which on 

 the distal segments is replaced by a single one. From P 4 to about PI O there is a high 

 crest running from the second to the fourth or sixth segment. This crest is interrupted 

 at the articulations. 



Notes. In a specimen from station 2079, according to Gislen, the centrodorsal 

 is flat, 4.5 mm. in diameter, and the cirrus sockets are arranged in a partially double 

 row. The cirri are XXI, 29-34, from 18 to 22 mm. long. The longest proximal 

 cirrus segments are half again as broad as long, and the distal segments are twice as 

 broad as long. The distal segments are provided with long sharp dorsal spines, which 

 begin abruptly on from the thirteenth to the sixteenth segment. The 19 arms are 

 about 85 mm. long. Of the seven IIBr series present four are 4 (3+4), one is 2, and 

 two are 5 (3+4). There are two IIIBr 2 series, both developed internally. The first 

 syzygy is between brachials 3+4;, the second between brachials 5 + 6, or sometimes 

 between brachials 9 + 10, and the third at about brachials 15 + 16; the distal inter- 

 syzygial interval is 7 to 10 muscular articulations. P D is 7.5 mm. long, with 21 seg- 

 ments. P, is 9.5 mm. long, with 22 segments. P 2 is 12 mm. long, with about 24 seg- 

 ments. P 3 is of about the same length as P 2 but has fewer segments. P 4 is shorter 

 than P 3 . The proximal pinnules are rather smooth but angular in section, with a low 

 double longitudinal carination, which on the distal segments is replaced by a single 



