296 BULLETIN 82, UNITED STATES NATIONAL MUSEUM 



the disk with arms nearly or quite 200 mm. long. He said that there is no little diver- 

 sity in the sculpturing and ornamentation of the calyx and arm bases, but on the whole 

 the species characters (of insculpta) are well maintained. 



CRINOMETRA BREVIPINNA »ar. GRACILIS (Hartlaub) 



Antedon brevipinna var. gracilis Hartlaub, Mem. Mus. Comp. Zool., vol. 27, No. 4, 1912, p. 322 

 (in key), p. 328 (description; Blake station 157), pi. 12, fig. 3. 



Description.— This variety was described from a single specimen with the arms 

 about 75 mm. long from Blake station 157. 



Hartlaub said that at first sight this specimen is noteworthy by its slender habitus 

 resulting from its long, narrow, and laterally compressed arms. There is no darkening 

 of the centrodorsal and the postradial series. Except for the somewhat darker deeply 

 incised disk it is, in alcohol, of a brilliant white color. 



Its significant differences from var. insculpta (decora) are as follows. The very 

 flat centrodorsal has fewer cirri with few segments, the cirri being XVI, about 12; the 

 penultimate segment bears an opposing spine. 



The fine lamellaelike protuberances are qualitatively and quantitatively less 

 developed on the centrodorsal and on the only slightly everted lateral borders of the 

 ossicles of the division series and first four brachials; similarly, the number of the 

 tubercles or swellings on the division series and lower brachials is small; in contrast to 

 var. insculpta (decora), there are here broad and large lumps and swellings. As a 

 result, the division scries have a far less rough appearance. The lips on the lower 

 brachials are finer. 



All the IIBr series are 2, and there is one IIIBr 2(1 + 2) series so that the number 

 of arms is 21. Almost throughout, the first syzygy is between brachials 1+2 and the 

 second between brachials 3+4, so that the arms begin with two syzygial pairs, except 

 for the two arms arising from the IIIBr axillary in which the first syzygies are between 

 brachials 5+6 and 8+9. In marked contrast to this is the sequence of syzygies in 

 arms arising from the IIBr axillaries. The next syzygy is from between brachials 

 11 + 12 to between brachials 13+14, most commonly by far between brachials 12 + 13; 

 the next is from between brachials 17+18 to between braclrals 20+21, usually between 

 brachials 19 + 20, and those succeedmg follow most commonly at mtervals of 5, 6, and 

 7, very rarely 8 and 10, muscular art ; culat : ons. Thus the syzygies are characteristi- 

 cally close together. 



Pi is 6 mm. long with 20 segments of which usually only 4 and at the most 6 of 

 tho basal are broadened, with fully double or more strongly single keels. The pinnules 

 succeeding, gradually decreasing from 5 to 4 and to 3 mm. in length to the eighth 

 brachial, have moderately broadened proximal segments which are followed by elongate 

 ones. The pinnules of the middle portion of the arms are about 3 mm. long with, 

 as a rule, 10 segments of which the first two are short and the first is markedly broadened. 

 Tho ambulacral plating consists of side and covering plates. The sacculi are 

 small and inconspicuous. 



Locality. — Blake station 157. 



Geographical range. — Known only from off Montserrat, British West Indies. 



Bathymetrkal range. — Recorded only from 219 meters. 



