A MONOGKAPH OF THE EXISTING CRINOIDS 89 



(P. Brachials triangular, about as long as broad, becoming elongate wedge-shaped distally 

 (Bahamas and Dry Tortugas, throughout the Caribbean Sea, and southward to Bahia, 



Brazil; 0-355 meters) Nemaster, p. 214. 



b 2 . Outer cirrus segments not carinate dorsally, the dorsal processes, including the opposing spine, 

 in the form of a straight transverse ridge; arms 10-19, but usually 10, and very rarely 

 over 13, in number (Bass Strait and coast of Victoria; 119 [?91]-183 [?311] meters). 



Comanthoides, p. 240. 

 a 5 . Arms 10 in number. 



6'. All the pinnules present. 



c 1 . Cirri never excessively slender; arms more than 20 mm. in length. 



d 1 . Outer cirrus segments more or less sharply carinate dorsally, the dorsal processes median 



spines or tubercles or spinous V-shaped elevations with a sharp median apex. 

 e l . First and second segments of the proximal pinnules with a very high and prominant 

 carinate process, of which the crest, at least on the second segment, is parallel with 

 the longitudinal axis of the pinnule (Caribbean Sea and Gulf of Mexico; 0-479 



meters) Leptonemaster, p. 275. 



e 1 . No carinate processes on the basal segments of the proximal pinnules. 

 /'. Pinnules of the first 2, 3, or 4 pairs with terminal combs which are confined to the 

 distal half and are composed of teeth which are seldom, and never much, higher 

 that the width of the segments bearing them; none of the segments of the proximal 

 pinnules more than very slightly longer than broad; no modification of the dorsal 

 surface of the lower brachials; brachials and pinnule segments with very spinous 

 distal edges (Seychelles, Amirante Islands, the Red Sea, and Ceylon to northern 

 and eastern Australia, the Bonin Islands, southern Japan, the Philippines, and 



Macclesfield Bank; 0-984 meters) Comissia, p. 244. 



f 3 . Terminal comb occurring only on the pinnules of the first pair (Pi and P a ), from 

 one or both of which it may be absent; combs arising at about, or even proximal 

 to, the end of the proximal third of the pinnule, and composed of exceptionally 

 large rounded teeth which usually much exceed in height the width of the seg- 

 ments bearing them; usually one or more of the earlier segments of PI twice as 

 long as broad, or even longer; fourth-seventh brachials each with a prominent 

 spinous median knob or keel (Key West, Fla., to Cape Lookout, N. C.; 14-241 



meters) Comatonia, p. 288. 



rf 3 . Outer cirrus segments not carinate dorsally, the dorsal processes, including the opposing 

 spine, in the form of a straight transverse ridge; arms 10-19, but usually 10, and very 

 rarely over 13, in number (Bass Strait and the coast of Victoria; 119[?91]-183 [?311] 



meters) Comanthoides, p. 240. 



c 2 . Cirri excessively slender and threadlike, the enormously elongated segments with greatly 

 swollen articulations; penultimate cirrus segment, which is much shorter than those pre- 

 ceding, twice as long as broad; arms not more than 15 mm. in length (Virgin Islands; 91-183 



meters) Microcomatula, p. 287. 



ft 2 . Second, third, and fourth pairs of pinnules absent, there being no pinnules between PI and P 5 

 and P a and P e (off Georgia; 512 meters) Comatilia, p. 284. 



Genus COMATELLA A. H. Clark 



Aclinometra (part) LUTKEN, Mus. Godeffroy Cat., vol. 5, 1874, p. 190, and following authors. 



Comatula (part) LTJDWIO, Zeitschr. f. wiss. Zool., vol. 26, 1876, p. 361. 



Antedon (part) VON GRAFF, Challenger Reports, Zoology, vol. 10, part 27, 1884, p. 13. 



Calometra (part) A. H. CLARK, Smiths. Miscell. Coll. (Quarterly Issue), vol. 50, part 3, 1907, p. 363. 



Phanogenia (part) A. H. CLARK, Proc. U. S. Nat. Mus., vol. 33, 1908, p. 124. 



Comaster (part) A. H. CLARK, Proc. U. S. Nat. Mus., vol. 33, 1908, p. 686. 



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