A MONOGRAPH OF THE EXISTING CRINOIDS 307 



20-30 segments of which the hasal 4-7 are broad and more or less doubly keeled. The 

 immediately following pinnules are of the same length as P,, and the pinnules in the 

 middle of the arm, from about the twentieth brachial onward, are 6-8 mm. long with 

 12-15 segments. 



Localities. — Blake stations 198 and 219. 



Geographical range. — Martinique and St. Lucia. 



Bathymetrical range. — From 250 to 276 meters. 



Thermal range— From 11.39° to 13.89° C. 



CRINOMETBA BREVIPINNA Tar. MARGARITACEA A. H. Clark 



Plate 31, Figure 94 



[See also vol. 1, pt. 2, figs. 683, p. 338, 746, p. 349.] 



Crinometra margaritacea A. H. Clark, Proc. U. S. Nat. Mus., vol. 36, 1909, p 645 (description; 

 Albatross station 2154); U. S. Nat. Mus. Bull. 82, vol. 1, pt. 2, 1921, fig. 683, p. 338. 



Description. — The centrodorsal is thick discoidal or flattened hemispherical with 

 the bare polar area 3 mm. in diameter, covered with small high tubercles. The cirrus 

 sockets are arranged in 10 closely crowded and somewhat irregular columns, two to a 

 column, the columns sometimes with a row of small tubercles between them. 



The cirri are XX, 13-15, 20 mm. long. The first segment is very short, the second 

 and third are twice as broad as long, the fourth is as long as, or somewhat longer than, 

 broad, and those following are about one-third again as long as broad, or rather less, 

 becoming about as long as broad toward the end of the cirrus. The antepenultimate 

 segment is slightly longer than those preceding. The penultimate segment is twice as 

 long as broad, slightly less in diameter than those preceding. The cirrus segments 

 have slightly prominent distal ends, and the last sLx or seven have a slight low and 

 broad tubercle in the median line of the distal edge on the dorsal side which becomes 

 more prominent distally. The opposing spine is very small, terminal in position, directed 

 obliquely forward. The terminal claw is about three-quarters the length of the penulti- 

 mate segment, moderately slender and moderately curved. 



The ends of the basal rays are visible in the angles of the calyx. They bear one 

 or more long tubercles. 



The radials are concealed. The IBri are very short, five or six times as broad as 

 long, with the edges parallel and slightly curved. The IBr 2 (axillaries) are rhombic, 

 about two and one half times as broad as long. The IIBr series are 2. The IIIBr 

 series are 2, developed interiorly, but never present in the full series. Tho division 

 series and first two brachials are slightly convex dorsally and are laterally in close 

 apposition and sharply flattened. The axillaries are separated on their lateral contig- 

 uous edges, forming rhombic water pores. The first and second brachials are similarly 

 separated interiorly. The ornamentation consists of moderately large blunt tubercles 

 distributed evenly over the surface of the division series, becoming less marked after 

 the second brachial and gradually disappearing at about the end of the proximal fourth 

 of the arms. The IIBr and IIIBr series and the first two brachials have a low but 

 prominent rounded narrow median carination. This is continued on to the arm 

 bases in the shape of prominent median tubercles on each brachial, these tubercles 

 disappearing at about the end of the proximal fourth of the arms. The arms are 

 practically smooth in the distal two-thirds. 



