68 



BULLETIN 82, UNITED STATES NATIONAL MUSEUM 



VOLUME 1 



by Chadwick in 1908. In a review, published in 1909, of Mr. Chadwick's 

 paper, I called attention to the relatively large number of cirrus segments 

 in the specimen as described by him and suggested that it might find its place rather 

 with the nana group of species than with parvicirra, a supposition which subsequently 

 proved erroneous. 



Only a single individual was discovered which I examined in the British Museum 

 in 1910. It seemed so different from any of the related species that I described it as a 

 new form under the name of Iridometra aegyptica in 1911 (redescribing it in 1913), 

 which name in 1917 was changed to Dorometra aegyptica. 



DOROMETBA CLYMENE A. H. Clark 



Figure 3, a-c 



Dorometra dymene A. H. CLARK, Journ. Washington Acad. Sci., vol. 7, No. 5, 1917, p. 128 (listed); 

 Unstalked crinoids of the Siboga-'Exped., 1918, p. 215 (in key; range), p. 217 (description; Sta. 

 167), p. 273 (listed). 



Diagnostic features. P 2 is intermediate in length between Pj and P 3 , all three of 

 these pinnules having 8 or 9 segments, and the cirri are excessively slender and delicate, 

 the longer segments being about four times as long as the width of the expanded ends. 



Description [modified by A.M.C.]. The centrodorsal is obscured from view by 

 the cirri which appear to have a tendency towards arrangement in vertical columns 

 each of about two cirri. As the arms are curled up dorsally a lateral view of the 

 centrodorsal is difficult. The cirri are long and slender, those nearer the apex being 

 very much more slender than the peripheral ones which have up to 12 segments and 

 may be 9 mm. long. The second segment is already over twice as long as its median 

 (minimum) breadth and the next three or four segments are five to six times their 

 median widths. The distal segments shorten relatively but the penultimate is still 

 twice as long as broad; it has no opposing spine. The terminal claw is long, very 

 slender and slightly curved. 



FIGURE 3. Dorometra dymene A. H. Clark, holotype: a, Proximal part of postradial series; b, cirrus of second row 

 from periphery; c, segment of apical cirrus, d, Dorometra nana (Hartlaub) from Siboga station 250, peripheral 

 cirrus. 



