430 BULLETIN 8 2, UNITED STATES NATIONAL MUSEUM 



The radials are nearly as long as the IBri in the median line, about 4 times as 

 long as broad, with the proximal and distal borders approximately straight and 

 parallel; they bear in the center a prominent and rather high blunt median ridge 

 which in lateral view shows an evenly and strongly convex profile. The IBrj are 

 about three times as broad as long in the midradial line or slightly broader, with the 

 distal border gently concave. They bear a well-rounded medioposterior tubercle 

 which is situated about one-third of the way between the proximal and distal borders. 

 This tubercle rises very gradually both proximally and distally so that in a profile 

 view its sides are seen to be nearly straight; in a direct dorsal view it appears as a 

 rather broad median carination. The IBrj (axillaries) are about twice as broad as 

 long with the lateral angles broadly truncated, the lateral borders being about two- 

 thirds as long as those of the IBr,. There are 3 very faintly indicated elevations on 

 the dorsal surface in the form of low and obscure broadly rounded elongate tubercles 

 which scarcely rise above the general surface One of these is situated just proximal 

 to each distal face to which its longer axis stands at right angles, while the third, 

 rarely to be made out at all, is situated in the median line in the proximal half of the 

 ossicle. The lateral borders of the IBr2 are swollen and everted, forming a narrow 

 rounded lateral border which is continued for a greater or lesser distance proximally 

 on to the IBrj. The IIBr series are 2, resembhng the IBr series, except that on the 

 axillaries the medioposterior ridge is more prominent than the 2 anterior; the swollen 

 border of the IBr2 is continued out along the outer side of the IIBri and disappears 

 at the distal margin of the IIBr2. 



The 20 arms are about 70 mm. long. A faint well-rounded median ridge runs 

 along the dorsal surface of the arm, gradually transforming into the distal carination. 



P, is 7 mm. long with 15 segments. P2 is 10 mm. long with 15 segments of which 

 the distal are elongated with produced and spinous distal angles. P3 is 11.5 mm. long 

 with 14 segments, resembling P2. P4 is similar to P3. Ps is 10 mm. long, slightly 

 stouter, with 13 segments. Pa is 11 mm. long with 13 segments, resembling P5. The 

 distal pinnules are 12 mm. long. 



Notes. — The specimen from Willebrord Snellius station 60* has 20 arms 90 mm. 

 long. The cirri are 50-55 mm. long with 70-76 segments. 



The specimen from Banda is a particularly fine example with 20 arms 115 mm. 

 long. All the IIBr series are present. The cirri are XX, 109-113, up to 128 mm. in 

 length. On the centrodorsal the columns of cirrus sockets, which consist of three, 

 two, or one sockets, are separated interradially by a narrow line, and in the midradial 

 line by a bare line about twice as broad, nearly as broad as a cirrus socket. The dorsal 

 pole of the centrodorsal is almost flat with, in the center, a rosette of five low radially 

 situated tubercles. 



The specimens from the Danish Expedition to the Kei Islands station 24 present 

 the following details. One has 20 arms 120 mm. long. On the centrodorsal the col- 

 umns of cirrus sockets are in contact interradially but are separated by a narrow space 

 in the midradial line. The cirri are XVI, 90-102, 117 mm. long. Another has 18 

 arms 90 mm. long, IIBr series being absent from one postradial series. On the centro- 

 dorsal the columns of cirrus sockets are separated by a narrow groove interradially 

 and in the midradial line by a bare area about as broad as the sockets. The cirri are 

 XVI, 71-87, 65-85 mm. long. One has 20 arms. The centrodorsal has the dorsal 



