362 BULLETIN 82, UNITED STATES NATIONAL MUSEUM 



Description qf the type specimen. — The centrodorsal is a small thin disk with the 

 slightly concave dorsal pole about 1 mm. in diameter. 



The cirri are IX, segregated on the interradial angles of the centrodorsal in 4 

 pairs, the remaining angle having a single one. The cirri are all broken. Ten stumps 

 remain of which the longest is 5.5 mm. long and consists of 10 segments of which 

 the first is short and the remainder are about one-third again as broad as long. 



The radials are very short, just appearing beyond the centrodorsal. The ele- 

 ments of the IBr series are very closely united, externally appearing as if by syzygy. 

 The IBr series as a unit are broadly pentagonal, twice as broad as long. The IBri 

 are laterally united. The IBr2 (axillaries) are triangular, with the lateral angles not 

 in apposition. 



The 10 arms are 70 mm. long. The first 2 brachials are united by what appears 

 to be a perfect syzygy, forming a wedge-shaped pair which is about twice as broad as 

 long in the median line. The first brachial is short, with the proximal and distal 

 edges parallel, and the second is triangular, twice as broad as the exterior length. 

 The third and fourth brachials form a short and nearly oblong syzygial pair which 

 is about twice as broad as its maximum length. The following 3 brachials are short, 

 slightly wedge-shaped, nearly three times as broad as long, and those succeeding be- 

 come triangular, twice as broad as long, with the distal edge slightly concave and the 

 outer side slightly convex. The brachials gradually increase in length distally and 

 in the outer part of the arm become wedge-shaped, and distally about as long as broad. 

 In the median line of the dorsal surface of the arm there runs a narrow low rounded 

 carination which is rather prominent and is continued to the arm tip. The arms in- 

 crease slightly and gradually in width to the twelfth or fourteenth brachials, thence 

 tapering slowly distally. 



Syzygies occur between brachials 1 + 2 and 3 + 4, again from between brachials 

 11 + 12 to between brachials 13 + 14 (usually in the latter position) and between 

 brachials 16 + 17 or 17+18 (usually in the latter position), and distally at intervals 

 of from 3 to 5 (usually 4) muscular articulations. 



The pinnules resemble those of Comatula pectinata. The second segment of the 

 second and third pinnules is more or less enlarged and carinate dorsally, this feature 

 being most marked on P2; the third segment is similarly, but much less noticeably, 

 modified. 



The color in alcohol is deep purple. 



Notes. — The 2 specimens from Siboga station 99 are both small with the arms 

 30 mm. long and the cirri X, arranged in 5 interradial pairs. 



The specimen from the Danish expedition to the Kei Islands station 67 is typical; 

 the cirri are X, in 5 interradial pairs. 



The specimen from Siboga station 144 is small with the arms 45 mm. long and 

 V cirri; the interradial areas of the disk proximal to Pi are thickly studded with cal- 

 careous deposits. 



The larger specimen from Siboga station 318 has 11 arms 125 mm. in length; 

 the cirri are VI, 4 of them grouped in 2 interradial pairs and 2 occurring singly. The 

 arms are of the slender type and, except for the characteristic arrangement of the 

 cirri, the animal bears a close resemblance to that upon which Liitken based the name 



