A MONOGRAPH OF THE EXISTING CRINOIDS 251 



The second brachial is larger and much more obliquely wedge-shaped. The first 

 syzygial pair (third and fourth brachials) is somewhat longer interiorly than exteri- 

 orly, about twice as broad as the interior length. The following 1 or 2 brachials are 

 almost oblong, about three times as broad as long, then becoming triangular, about 

 twice as broad as long, and in the terminal part of the arm very obliquely wedge- 

 shaped, about as long as broad. The brachials after the second have prominent and 

 finely spinous distal ends and a very finely tubercular or spinous dorsal surface, which 

 in the terminal portion gradually become obsolete, so that the ends of the arms are 

 practically smooth. 



Syzygies occur between brachials 3 + 4, again between brachials 11 +12 to 14 + 15, 

 and distally at intervals of 3 muscular articulations. 



Pj is from 12 to 15 mm. long, slightly stouter than the succeeding pinnules, 

 though not especially large, with about 35 segments which at first are about twice as 

 broad as long, very gradually becoming longer, and about as long as broad after the 

 twelfth or fifteenth. The terminal comb is prominent, arising abruptly, composed of 

 16 teeth which are bluntly triangular, nearly twice as long as broad at the base, basally 

 in apposition, about as high as the height of the segments which bear them, and rather 

 strongly recurved. P 2 is similar, from 10 to 12 mm. long. P 3 is similar, from 8 to 

 10 mm. long. P 4 is 6 mm. long. P 5 and the following pinnules are 6 mm. long, with- 

 out combs, composed of 16 segments, of which the first 3 are not so long as broad and 

 the remainder are about as long as broad. Distally the pinnules gradually increase 

 in length and become more slender, the outer pinnules being 8 mm. long with from 

 23 to 25 segments, of which the first 2 are short, the third and following longer than 

 broad, and the outer about twice as long as broad. The lower pinnules have the 

 corners of the component segments considerably cut away. The segments of the 

 middle and distal pinnules are slightly constricted centrally with a finely spinous 

 surface and with the distal ends produced ventrally into two long sharp spines, one 

 on either side of the perisome; this modification of the segments in the more proximal 

 of the middle pinnules affects only the distal portion, later encroaching more and 

 more upon the proximal part and soon involving almost all the segments. 



The lateral perisome of the pinnules is almost naked, containing merely a few 

 very slender and inconspicuous, usually widely scattered, spicules. 



The disk is naked, or with small scattered calcareous granules. The mouth is 

 subcentral and the anal tube is small and marginal. 



Notes. Speaking of the specimen recorded as Comanthus spanoschistum from off 

 Noosa Head, Queensland, Dr. H. L. Clark says that it "is noticeably more slender 

 than the others and the cirri are somewhat more compressed, but these differences 

 are very slight and no more than one might expect in view of the wide separation of 

 Noosa Head from the Tasmanian waters, where this species [Comanthoides spano- 

 schistum] seems to be so common." 



The specimen from Siboga station 260 has the arms about 100 mm. long and 

 the cirri XIV, 23-25, about 15 mm. long. 



One of the specimens from the Danish expedition to the Kei Islands station 24 

 may be described as follows. 



The centrodorsal is discoidal, rather thick, with the slightly convex dorsal pole 

 3 mm. in diameter. The cirrus sockets are arranged in a single fairly regular mar- 



