98 BULLETIN 82, UNITED STATES NATIONAL MUSEUM 



proximal border becomes slightly raised, forming a low transverse ridge visible in 

 lateral view as a slight tooth near the proximal end of the segment. At about the 

 middle of the cirrus, when the proximal transverse ridge has become considerably 

 shortened, the central portion of the distal end on the dorsal side becomes prominent, 

 projecting dorsally as a shorter transverse ridge broadest in the middle so that the 

 crest is triangular when viewed dorsally. When viewed laterally the last 8 or 10 

 segments before the penultimate are seen to be provided dorsally with two low but 

 prominent and practically equal teeth, one near either end. In dorsal view the proxi- 

 mal process, though progressively narrowing toward the tip of the cirrus, is seen to be 

 broader than the distal. The opposing spine is median or submedian, very slender, 

 sharp, and erect, much longer than the processes on the preceding segments, its 

 height being equal to one-fourth or one-third the width of the segment. The terminal 

 claw is som.ewhat longer than the penultimate segment, rather slender, and more 

 strongly curved proximally than distally. 



In less-developed cirri the lateral width increases gradually from about the end 

 of the proximal third, reaching a maximum in the distal third. The distal ends of 

 the segments are rather strongly sinuate. The segments, especially the longer ones, 

 are slightly constricted centrally. 



A typical cirrus may be described as follows. The first segment is very short, 

 3 or 4 times as broad as long, the second is about half again as broad as long, and the 

 fourth or fifth is about as long as broad. The next 5 to 8 segments are somewhat 

 longer than broad, those succeeding becoming shorter again, the last 9 or 10 being 

 usually about as long as broad, or slightly broader than long. The cirri become rather 

 strongly compressed in the outer half, which is strongly recurved. 



The distal portion of the radials is visible beyond the lim of the centrodorsal, 

 forming a band 7 or 8 times as broad as the median length. The distal edge of the 

 radials is straight, and their lateral edges are separated by a very narrow V. The 

 IBri are almost oblong, between 3 and 4 times as broad as long. The lateral borders 

 are very slightly divergent — almost parallel — and the proximal and distal borders are 

 straight. The IBr2 (axillaries) are almost triangular, somewhat broader than long, 

 with the truncated lateral angles forming short lateral borders about one-third as 

 long as the lateral borders of the IBrj, with which they make a broadly obtuse angle. 

 The anterior edges are straight, and the anterior angle is only slightly less than a right 

 angle. The lateral edges of the elements of the division series and first two brachials 

 are somewhat swollen. 



The 10 arms are about 45 mm. in length. The first brachials are wedge-shaped, 

 twice as long exteriorly as interiorly, and about two and one-half times as broad as 

 the exterior length. The inner ends of adjacent first brachials are in contact interiorly 

 in their proximal third, the outer two-thirds diverging at an obtuse angle. The 

 second brachials are somewhat larger and more obliquely wedge-shaped than the first. 

 The first syzygial pah- (composed of brachials 3+4) is half again as long interiorly as 

 exteriorly, trapezoidal, with the distal edge at right angles to the longitudmal axis 

 of the arm and the proximal edge strongly oblique. The next 4 brachials are oblong, 

 rather more than twice as broad as long. The brachials succeeding become very 

 obliquely wedge-shaped, ahnost triangular, with the longer side somewhat convex, 



