278 BULLETIN 82, UNITED STATES NATIONAL MUSEUM 



fellow by the anterior apex of the IBr 2 , the interior edges of the two diverging at an 

 angle of approximately 90, or slightly less. The second brachial is irregularly 

 quadrate, slightly larger than the first. The first syzygial pair (third and fourth 

 brachials) is oblong, about half again as broad as long. The next 3 brachials are 

 approximately oblong, about twice as broad as long, the following becoming obliquely 

 wedge-shaped and after the tenth triangular, about as long as broad, farther out on 

 the arm very obliquely wedge-shaped, about as long as broad, and in the terminal 

 portion longer than broad. After about the sixth the brachials develop strongly 

 produced and overlapping distal ends. 



Syzygies occur between brachials 3 + 4, Again between brachials 10+11 to 

 12+13, and distally at intervals of 3 muscular articulations. 



PI is 10 mm. long, moderately stout basally and evenly tapering, composed of 

 about 35 segments. The terminal comb has 13 to 15 teeth, preceded by 2 or 3 more 

 or less rudimentary. The teeth are spade-shaped or triangular, higher than broad, 

 slightly higher than the height of the segments which bear them, well separated, and 

 incurved. The basal segments of the pinnule are broader than long, the propor- 

 tionate length gradually increasing so that the segments from the middle onward 

 are approximately squarish. The segments have prominent dorsal projections, with 

 the apex at the distal end, and strongly produced distal edges, these characters dying 

 gradually away after about the middle of the pinnule. P 2 is much more slender 

 than PI, 7 mm. long, with the segments after the fifth squarish. The first two seg- 

 ments have strong dorsal processes or broad carinations, that of the second the 

 stronger. The following segments have rounded dorsal processes and prominent 

 distal edges. The terminal comb is rather long, with 16 fully developed and 5 or 6 

 smaller and more rounded teeth. The teeth are proportionately slightly longer and 

 better developed than the teeth of PI. P 3 is about 4 mm. long, slender and delicate, 

 with the first 2 segments disproportionately large, about half again as broad as long, 

 the second with a much produced distal dorsal angle or even distal half of the dorsal 

 side; the third segment is squarish, and the following segments are slightly longer 

 than broad. The third and following segments as far as the comb, as in P 2 , have 

 strongly produced and coarsely spinous distal ends. The comb is as in P 2 . P 4 is 

 3.5 mm. long, slightly more delicate than P 3 , with no enlargement of the 2 basal 

 segments, and no comb. The first two segments are short, the third is longer than 

 broad, and the following increase slightly in length, being about half again as long 

 as broad distally. The third and following segments have produced and coarsely 

 spinous distal edges. P 5 is similar to P 4 , 4 mm. long with 16 segments, but slightly 

 stouter. The following pinnules are similar to P 6 , increasing very gradually in 

 length. The distal pinnules are 8 mm. to 9 mm. long, slender, with about 21 segments, 

 the first 2 not so long as broad, the third slightly longer than broad, the following 

 becoming elongated and about three or four times as long as broad distally. The 

 third and following segments have expanded articulations and coarsely spinous distal 

 ends. 



In the lateral perisome of the pinnules are slender, very delicate, and more or 

 less irregular, sometimes branched, rods, evenly spaced, lying at right angles to the 

 border of the pinnulars, sometimes in groups of 2 or 3, about 3 (or 3 groups) to a pin- 



