A MONOGRAPH OF THE EXISTING CRINOIDS 381 



The color in alcohol is white. 



Notes. — The preceding description is based upon specimens at hand from Alba- 

 tross stations 2159 (10), 2160 (5), 2103 (3), 2166 (4), 2169 (1), 2320 (3), 2323 (9), 

 2326 (6), 2327 (11), 2329 (1), 2331 (5), 2335 (2), 2337 (1), 2338 (1), 2342 (2), from 

 Fish Hawk station 6063 (4), and from Albatross material dredged "off Havana" (9). 



These specimens correspond to those which were distinguished by Ilartlaub as 

 var. valida. To this variety which, according to him, is distinguished from var. 

 echinoptera and var. meridionalis especially by its size, its color, and its massive struc- 

 ture, he assigned only a small number from among the specimens examined by him. 



He believed this variety to be the same as the new species Adinometra blakei, 

 which Carpenter had intended to describe. 



In its appearance it is wholly different from most of the specimens of var. 

 meridionalis, so that it gives the general impression of being a quite different species. 

 But a closer study shows a very marked agreement in most features, and furthermore 

 the material studied by Hartlaub included several intermediate specimens which he 

 distinguished as var. valida-meridionalis. 



In var. valida, as described by Hartlaub, the centrodorsal is relatively large, 

 5 mm. in diameter, and always bears numerous cirri which are usually arranged in 

 two marginal rows. 



The cirri are about XXV-XXX, and in their form resemble those of var. 

 meridionalis. 



In the larger specimens the arms reach a length of about 200 mm. 



The elements of the IBr series and the first 2 brachials are in lateral apposition, 

 and the 2 second brachials on a single post-radial series are usually in close apposition 

 internally, though in a given individual there may be some e.xceptions to this last. 

 As a result of the excessive shortening on the inner side of the arms the second 

 brachials have a very characteristic form. Articular tubercles are sometimes 

 developed. The proximal brachials are broad and flat. The syzj^gial pairs are not 

 longer — indeed individual ones are even shorter — than the single brachials. The 

 shape of the brachials remains the same from the eighth until far out on the arm, in 

 one specimen as far as the one-hundredth brachial; they are very uniformly 

 triangular. The dorsal surface of the arms is smooth from about the thirtieth brachial 

 onward. The first 5 or 6 brachials are exceptionally short. 



The intersyzygial interval is usually greater than in var. meridionalis, often 5 or 6 

 muscular articulations, but sometimes more. 



The relative length of the pro.ximal pinnules is variable. Sometimes Pj is almost 

 as long as Pi and the length of the succeeding pinnules decreases to that of the twelfth 

 brachial. In other cases the pinnule of the sixth or eighth brachial is the shortest. 

 The relationships of the pinnules may vary in a single individual, as for instance in one 

 from Blake station 277. Sometimes the pinnule of the sixth brachial bears a poorly 

 developed comb. There is no carination of the basal pinnule segments. 



Hartlaub remarked that the distinctive features of this variety are best shown by 

 2 specimens from Dominica or Guadeloupe, 4 from Blake station 277, 2 from which 

 the label has been lost but which are apparently from lat. 23° 52' N., long. 88° W., 

 or from lat. 25° N., long. 84° W., and 1 from Blake station 157. 



