184 BULLETIN 82, UNITED STATES NATIONAL MUSEUM 



so that the pinnule as a whole reminds one strongly of P 2 in the genus Cenometra. 

 P 3 is similar to P 2 but smaller and much more slender and flagellate distally, 10 mm. 

 long with 19 segments. P and the following pinnules are 6 mm. long, small, weak 

 and slender. The distal pinnules are very slender, 10 mm. in length. 



Notes. The preceding description is the original description drawn up in the 

 British Museum from the type specimen. 



In 1928 the British Museum submitted to me, thanks to the kindness of C. C. A. 

 Monro, two additional specimens from the type locality for study. One of these was 

 large and one was much smaller. In the larger individual the centrodorsal is thin 

 discoidal, with the dorsal pole broad and sunken in such a way that only the outer 

 border rises to the lower edges of the cirrus sockets. The cirri are arranged in a fairly 

 regular marginal row. The cirri are XX, 26, about 12 mm. long. The segments in 

 the proximal third of the cirri are about twice as broad as long, those succeeding 

 becoming about half again as broad as long, and the distal being only slightly broader 

 than long. On the third or fourth segment a ridge appears on the dorsal side hi the 

 shape of a broad V with a rounded apex; the two ends of the V lie at the distal outer 

 angles of the segment, and the rounded apex is just within the middle of the proximal 

 border. Almost immediately the apex of the V disappears, so that only two short 

 diagonal ridges are left, which, on about the twelfth segment, become reduced to a 

 pair of small tubercles, those on the antepenultimate fusing into a single median 

 tubercle. The radials in the midradial line are even with the rim of the centrodorsal. 

 The IBr, are short, about four tunes as broad as long, with the distal border some- 

 what concave and the lateral edges rather broadly in contact basally, diverging from 

 the point of contact at an angle of about 45. The IBr 2 (axillaries) are almost 

 triangular, about twice as broad as long. The short lateral edges make an angle of 

 about 90 with those of the IBr^ The 10 arms are about 100 mm, long. They 

 remain of uniform width for an unusual distance, and then taper very slowly. PI is 

 7 mm. long with 17 segments of which the first is twice as broad as long, the fourth 

 is about as long as broad, and those following are about half again as long as broad. 

 The pinnule is rather stout basally, but tapers rapidly in the proximal third, and 

 more gradually from that point onward; it does not become flagellate distally. P 2 is 

 12 mm. long, much larger, stouter, and stiffer than P,, with about 18 segments of 

 which the first is half again as broad as long, the fourth is very slightly longer than 

 broad, and those following are about one-third again as long as broad. From the 

 fourth onward the segments have the distal edge abruptly and prominently everted 

 and dentate. P 3 resembles P 2 but is shorter and less stout. Usually the difference 

 is only slight, though it may be considerable. P 4 may be much shorter, more slender, 

 and less stiffened than P 3 , resembling the pinnules succeeding, or it may be inter- 

 mediate between P 3 and the following pinnules. The color in alcohol is purplish 

 brown with a narrow white band running directly across the arm in the middle of 

 each brachial. In the proximal fourth of the arms this light transverse band on the 

 pinnule side of the brachials suddenly expands, forming a ring about a large circular 

 brown spot. The enlarged lower pinnules are light with a central dark dot on more 

 or fewer of the basal segments. Some of the arms are light with narrow brown 

 bands along the articulations. The centrodorsal and the cirri are uniform in color 

 and rather dark. 



