A MONOGRAPH OF THE EXISTING CRINOIDS 267 



interradial angles as in the midradial line. The IBr ( are very short, 6-7 times as 

 broad as long, with the proximal and distal edges nearly straight and parallel, and 

 the lateral edges slightly divergent and slightly convex. The IBr 2 (axillaries) are trian- 

 gular with slightly truncated lateral angles, and are twice as broad as long. The anterior 

 angle is slightly greater than a right angle, and is slightly grooved at the apex. The 

 lateral borders of the IBr series and first two brachials are straight and are almost or 

 quite in contact with those of their neighbors. 



The 10 arms are 265 mm. long. The first brachials are wedge-shaped, about 

 twice as long exteriorly as interiorly, nearly four times as broad as the median length, 

 with the proximal and distal edges straight and parallel, and the inner edges united 

 basally, diverging at a right angle distally. The second brachials are similar to the 

 first, but the proximal and distal ends are slightly more oblique. The first syzygial 

 pair (composed of brachials 3+4) is oblong, nearly twice as broad as long. The 

 bra'chials following are wedge-shaped with the longer side more than twice as long as 

 the shorter, and about twice as broad as the greater length; after the sixteenth the 

 brachials become triangular with the proximal and distal edges somewhat sinuous, 

 half again as broad as long. After the proximal fourth of the arm the brachials slowly 

 become shorter with the ends less oblique, in the middle of the arm being wedge- 

 shaped and twice as broad as long. Distally the obliquity of the ends still further 

 decreases, and terminally the brachials increase in length, becoming as long as broad. 



Syzygies occur between brachials 3+4 and 9 + 10, from between brachials 11 + 12 

 to between brachials 15 + 16 (usually between brachials 14+15), and distally at inter- 

 vals of from 6 to 9 (usually 7 or 8) muscular articulations. On one arm syzygies occur 

 between brachials 3+4, 6+7, 10+11, and 15+16. 



PI is 22 mm. long, slender and evenly tapering, composed of 28 segments of which 

 the first is somewhat broader than long, the second is somewhat longer than broad, 

 and those following slowly increase in length so that the distal are about twice as long 

 as broad. From the fourth onward the segments have a sharp ridge on the outer 

 side which is slightly convex in profile and finely and irregularly serrate. The area 

 between this and the sharp ventral ridge is slightly concave. P 2 is 18 mm. long 

 with 27 segments and resembles PI. P 3 is 18 mm. long with 25 segments and resembles 

 the pinnules preceding, as does P 4 , which is 18 mm. long with 26 segments. P 6 is 

 19 mm. long with 28 segments and is very slightly stouter than the preceding pin- 

 nules. P 6 is 20 mm. long with 27 segments, and resembles P 6 . The pinnules following 

 are similar. P 25 is 17 mm. long with 27 segments. The distal pinnules are exceed- 

 ingly slender, 16 mm. long and with 30 segments which are very slightly constricted 

 centrally and have slightly serrate distal ends. 



The color in alcohol is white with a broad, irregular, and frequently interrupted 

 dorsal band of purple on the division series and arms. The cirri are more or less shaded 

 or spotted with purple, the segments often with purple saddles or spots, and the 

 distal pinnules are more or less blotched with purple. The color in life was recorded 

 as pale viridine yellow on the disk and arms, with the dorsal arm stripe taupe brown. 

 This change in color after preservation in alcohol recalls a similar case in Amphimetra 

 tessellata discoidea. A color sketch of a specimen of the latter from Siboga station 

 99 was made at the time of capture. This showed the animal as light yellow with the 

 ventral perisome of the arms and pinnules, though not the disk, dark yellow-brown. 



