100 BULLETIN S2, UNITED STATES NATIONAL MUSEUM 



The cirri are XXVII-XXXVII (usuaUy about XXX), 18-26 (usuaUy 20-25; 

 the variation in any individual is not more than from 4 to 6 segments, and usually 

 only 2 or 3), from 15 to 25 mm. long, the cii-ri in each specimen averaging usually 

 about 15 or 20 mm., most commonly the latter. The first segment is very short, and 

 the following increase in length to the fourth, which is a little longer than broad, 

 and the fifth-seventh or sixth-eighth, which are the longest, one-third, sometimes 

 nearly one-half, again as long as broad. The eighth, ninth, or tenth, rarely the 

 eleventh, twelfth, or thirteenth, is a transition segment which is about as long as 

 broad or sUghtly longer than broad, with the greater part of its surface dull like that 

 of the preceding segments, but the distal portion highly polished like those succeed- 

 ing. The following segments are at first about as long as broad, then gradually 

 decreasing in length so that the last 9 or 10, which are somewhat compressed later- 

 ally, are twice as broad as long, or even broader distally. The transition and follow- 

 ing segments have a sUght dorsal tubercle which is at first distal in position but gradu- 

 ally moves proximally, becoming submedian after 7 or 8 segments and median on the 

 last 4 or 5. The opposing spine is represented by a sUght median tubercle. The 

 terminal claw is longer than the penultimate segment and is stout and strongly 

 curved. 



The radials are nearly or quite concealed by the centrodorsal. 



The IBri are very short, closely united laterally, proximally more or less con- 

 cealed by the centrodorsal. The IBra are short and broad, somewhat over twice as 

 broad as long, triangular, and laterally free. The IIBr series are 2, almost invariably 

 all present. The IIIBr series are 2, usually all present, developed on the outermost 

 side of each postradial series in 2, 1, 1,2 order. IVBr series and even VBr series are 

 sometimes present, always developed exteriorly in reference to the IBr series, like 

 the IIIBr series. The division series are strongly rounded dorsally and laterally, 

 and are perfectly free laterally, though not very widety separated. The first seg- 

 ments following each axillary are interiorly united for rather more than one-half 

 their internal length, but widely separated distally. 



Arms 27-50 (usually 30-40), from 90 to 120 mm. in length, composed of about 

 120 brachials. The first 2 brachials are similar in size and shape, small, short, and 

 wedge-shaped. The next 4 or 5 brachials are oblong, approximately twice as broad 

 as long, and the following become triangular, at first nearly as long as broad, but 

 decreasing gradually in length and in obhquity and in the outer half of the arm 

 becoming very short and disicoidal and resembhng the distal brachials in Himeromeira. 

 All the brachials following the few oblong brachials at the base of the arm have 

 prominent and somewhat overlapping distal ends and a longitudinally striate dorsal 

 surface. 



Syzygies occur between brachials 14-2, except on the outermost arms of each 

 postradial series, 3 + 4, this being usuaUy omitted if the 2 preceding brachials are 

 united by syzygy, and from 11 + 12 to 16 + 17; the distal intersyzygial interval is 4, 

 rarely 3, muscular articulations. 



Pi is moderately stout basally, but becoming slender and flagellate in the distal 

 half, from 15 to 18 mm. long; the terminal comb has about 15 teeth, which are 

 triangular, approximately equilateral, slightly incurved, and about equal in height 



