292 BULLETIN 82, UNITED STATES NATIONAL MUSEUM 



equal to about one-third the width of the segment. The distal edge of the radials is 

 just visible beyond the rim of the centrodorsal ; it usually bears a single row of small 

 and regular beadlike tubercles, but it may be simply roughened. The division series 

 are broad, in close lateral contact, and laterally flattened. The lateral borders of 

 the elements of the division series are slightly produced, the production forming a 

 narrow margin with a straight outer edge. Of the eight IIBr series six are 4(3+4) 

 and two are 2. The two IIIBr series, which are both developed on the same IBr 

 series, are 2. The 20 arms are 150 mm. in length. The earlier brachials are wedge- 

 shaped, short, twice as broad as the maximum length; beyond the proximal third of the 

 arm the brachials become almost oblong and about four times as broad as the median 

 length. 



P D is 10 mm. long and is composed of 32 segments. It tapers rapidly on the first 

 nine segments, beyond which it is very slender. The first segment is much broader 

 than long, but those succeeding gradually increase in length so that the eighth and 

 following are about as long as they are broad. The first six segments are sharply 

 carinate, the carination being narrow with the crest straight and parallel with the 

 longitudinal axis of the segments. The first two or three segments are flattened 

 against the corresponding segments of the adjacent pinnule on the neighboring arm. 

 P t is about 13 mm. long and is composed of 34 segments. It tapers rather rapidly in 

 the first eight segments, becoming slender and flagellate distally. The segments 

 become as long as broad on the third to the sixth, then longer than broad, the last 10 

 being about twice as long as broad. The first seven segments are sharply carinate, 

 the carination being highest on the second and third, and disappearing at the end of 

 the seventh. P 2 is 19 mm. long and is composed of 33 segments, which become as 

 long as broad on the fourth and on the last 10 are twice as long as broad. The 

 second-seventh segments bear a sharp knifelike carinate process which is narrow with 

 a straight crest parallel to the longitudinal axis of the segments. The pinnule is 

 only moderately stout and tapers with extreme slowness from the base to the tip, 

 which gives it a straplike appearance. P 3 is 13 mm. long, with 27 segments, which 

 beyond the fifth are all about as long as broad. The second-sixth segments are sharply, 

 though narrowly, carinate. P 4 is 9.5 mm. long, with 23 segments, less stout at the 

 base than P 3 and tapering rather rapidly in the proximal half so that the distal half is 

 slender and flagellate. The segments become as long as broad on the sixth and twice 

 as long as broad terminally. The second-sixth segments are narrowly carinate. 



Another specimen from 80 miles northwest of Penang resembling the preceding 

 has 15 arms, there being four IIBr 4 (3+4) series and one IIIBr 2 series, the latter 

 developed internally. The longest cirri have 36-39 segments. 



A third specimen from the same locality has 12 arms 90 mm. long, there being 

 present two IIBr 4 (3+4) series. The longest cirri have 32-33 segments. 



The three other specimens from 80 miles northwest of Penang are more grayish 

 in color and slightly smoother in appearance. One has 14 arms 140 mm. long; there 

 are three IIBr 4 (3+4) series and a single IIIBr 2 series, the latter internally 

 developed. 



Another has 13 arms 130 mm. long; there are two IIBr 4 (3+4) series and one 

 IIIBr 2 series, internally developed. 



