PART 5 A MONOGRAPH OF THE EXISTING CRINOIDS 597 



nules. The number of columns of cirrus sockets probably increases with size as well 

 as the total number of cirri. C. monilicirra and atlantidis appear to be the only well- 

 marked species, distinguished by either very small or very few cirri relative to the size. 

 In his preliminary report on the comatulids of the Blake collection Dr. P. H. 

 Carpenter said that of all the Antedon species dredged by the U.S. Coast Survey the 

 one with the widest range within the Caribbean Sea is the little 10-armed A. (Cocco- 

 metra) hagenii. He wrote that it was obtained by the Blake on the Yucatan Bank 

 and also at various stations between Dominica and Grenada at different depths 

 between 75 and 291 fathoms, while Mr. Pourtales dredged it in great abundance at 

 several localities in the Florida Straits. He noted that the original type specimens 

 were obtained off Sand Key, and several individuals from Barbados and Grenada 

 differ so much both from them and from one another that he was at first inclined to 

 regard them as representing two new species, but a more careful examination did not 

 confirm this impression. It is probable that some, at least, of these specimens 

 represented species of Caryometra and Antedon. 



KEY TO THE SPECIES OF CARYOMETRA 



a 1 . Cirri with the distal segments shorter than the elongate proximal, the penultimate and more or 

 fewer of those preceding being not more than half again as long as broad, and usually not longer 

 than broad; an opposing spine present; terminal claw as long as, or longer than, the penultimate 

 segment and curved. 

 6'. Cirrus sockets arranged in 15 columns, 3 beneath each radial. 



c 1 . Elements of the division series and brachials without prominently everted and spinous distal 



ends, these being smooth or at most finely serrate. 



d l . Cirri with 30-35 segments; spicules in the perisome of the pinnules short, slender, usually 

 straight rods with unmodified ends, or occasionally with the distal end bifurcate (Cuba 



and Puerto Rico; 386 meters) tenuipes (p. 597) 



(P. Cirri with 17-28 (usually 20-25) segments; spicules abundant, slightly thorny, the distal 



end occasionally forked or expanded and perforated (Cuba; 713 meters) lisa (p. 603) 



c 2 . Elements of the division series and lower brachials with prominently everted and spinous 



distal ends; 2434 cirrus segments. 



d 1 . Cirri with the outermost 5 or 6 segments about as long as broad; IBri narrow with distally 

 converging lateral borders beyond which the lateral angles of the axillaries extend for a 

 considerable distance; spicules in the perisome of the pinnules slender and nearly straight 



rods (Cuba; 338-777 meters) alope (p. 605) 



<P. Cirri with the distal segments longer than broad; IBri broad with parallel lateral borders 



which are not overhung by the lateral angles of the axillaries; spicules in the perisome 



of the pinnules stout, branched at both ends (Cuba; 338-484 meters) ..spinosa (p. 608) 



b*. Cirrus sockets in 10 columns, 2 beneath each radial; cirri with 19-24 (usually 20) segments, 



strongly incurved distally, the last 10 or 12 segments about as long as broad, the outer half 



of the cirri moniliform (Cuba; 466 meters) monilicirra (p. 610) 



o j . Cirri very slender, only slightly curved distally, tapering to a fine point, the outermost segments 

 greatly elongated; no opposing spine; terminal claw minute and conical; 22 cirrus segments 

 (Cuba; ?Grenada; 366-530 meters) -- atlantidis (p. 612) 



CARYOMETHA TENUIPES < A. H. Clark) 



FIGURE 34 

 [See also vol. 1, pt. 1, fig. 380, p. 301] 



Adelomelra tenuipes A. H. CLARK, Proc. U.S. Nat. Mus., vol. 34, 1908, p. 236 (description; Albatross 

 station 2348); Unstalked crinoids of the Siboga-Exped., 1918, p. 233 (in key; range; references); 

 The Danish Ingolf-Exped., vol. 4, No. 5, Crinoidea, 1923, p. 42 (locality). 



