356 BULLETIN 82, UNITED STATES NATIONAL MUSEUM 



The cirri are XXV-XXX, 15-18. Nearly all the segments are longer than broad, 

 according to the figure mostly about twice as long as broad. There is but little trace 

 of an opposing spine, and the terminal claw is curved and sharp. 



The radials are visible only in young specimens. The IB^ are somewhat flattened 

 with a convex proximal and concave distal border. The IBr 2 (axillaries) are more 

 convex, broadly pentagonal or almost rhombic, with a wide distal angle and sometimes 

 projecting deeply posteriorly into the IBrj. The dorsal surface of the elements of 

 the IBr series, the first two brachials, and the hypozygal of the first syzygial pair 

 project beyond their faces and sides, especially the latter which fall away rapidly from 

 the dorsal towards the ventral border. 



The 10 arms are probably 100 mm. long and consist of about 100 brachials. The 

 first brachials are nearly oblong with rounded outer edges. The second are convex 

 and irregularly pentagonal. Those following are smooth and triangular, as long as 

 or longer than broad. 



Syzygies occur between brachials 3+4, again at about brachials 12 + 13 or 13+14, 

 and distally at intervals of from 3 to 6 (usually 4 or 5) muscular articulations. 



PI and P ft are composed of about 30 short segments the lowest of which is a good 

 deal wider than the others. In the pinnules from the fourth to the twenty-fifth brachial 

 about 3 to 5 of the segments are greatly expanded laterally to enclose the gonads, and 

 the first segment is much wider than its successors, especially in the lower pinnules. 

 The later pinnules have longer and more trihedral segments the lowest of which are 

 flatter. 



The disk is 5 mm. in diameter, rather incised, and completely covered with irreg- 

 ular plates bearing short and blunt rodlike spines. The brachial ambulacra and the 

 interarticular spaces are well plated, and the expanded parts of the genital pinnules 

 are completely enclosed in an arched pavement of flat plates very regularly arranged 

 and devoid of ambulacra. The ambulacra of the later pinnules have very well 

 defined side plates, sometimes covering the sacculi and sometimes notched for them. 

 These are very abundant except on the non-tentaculiferous genital pinnules. 



The color of young specimens in alcohol is straw color; the older ones are a dense 

 brownish gray, becoming a dark gray in the most mature. 



Notes. Carpenter said that in its general characters this species has many points 

 of resemblance with Charitometra basicurva, Ch. incisa, and Glyptometra tuberosa; but 

 the sides of the elements of the IBr series are not in close apposition and flattened 

 laterally against each other as in those types, for they fall away very rapidly from the 

 dorsal toward the ventral surface so that there is a considerable space between every 

 two postradial series, especially at the level of the articulation. This is smaller on the 

 surface than it is deeper down, for the lateral edges of the ossicle are produced out- 

 ward, like the projecting eaves of a roof. This condition is extremely marked in the 

 case of the IBrj, which has the proximal edge similarly produced so as to overlap the 

 minute portion of the radials which appears externally. 



Carpenter said that the relative shapes of the elements of the IBr series vary ex- 

 tremely. In some individuals the IBri are approximately oblong and show hardly any 

 indication of an incised distal edge, while the axillaries are broadly pentagonal. On 

 the other hand, the axillaries sometimes project far back into the IBr: which then have 

 a deeply incised distal edge, while the proximal edge is also much curved. 



