PART 5 A MONOGRAPH OF THE EXISTING CRIXOIDS 483 



in 1899 and described in 1912 and 1918, besides unpublished records of two others 

 taken in the same region by the Albatross in 1909, two in the Copenhagen Museum 

 from the northern end of Celebes and two more from the Kei Islands expedition. 



NANOMETRA BOWERSI (A. H. Clark) 



[See vol. 1, pt. 1, figs. 310 (p. 269), 390 (p. 307); pt. 2, figs. 106-107 (p. 67)] 



Anledon minor A. H. CLARK, Proc. U.S. Nat. Mus., vol. 33, 1907, p. 144 (description; Albatross sta. 

 4965) [preoccupied by a fossil species]. 



Anledon bowerfi A. H. CLARK, Proc. U.S. Nat. Mus., vol. 33, 1907, p. 148 (description; Albatross 

 sta. 4934). 



Antedon orientalis A. H. CLARK, Smithsonian Misc. Coll., vol. 50, pt. 3, 1907, p. 341 (description; 

 Albatross sta. 4933), p. 353 (listed). 



Nanomelra minckerti A. H. CLARK, Smithsonian Misc. Coll., vol. 50, pt. 3, 1907, p. 349 (new name 

 for Antedon minor A. H. Clark, 1907, preoccupied). 



Nanometra bowersi A. H. CLARK, Proc. U.S. Nat. Mus., vol. 34, 1908, p. 318 (Japan; considered as 

 including minor [minckerti] and orientalis) ; Crinoids of the Indian Ocean, 1912, p. 241 (synonymy; 

 includes minor, bowersi, orientalis and minckerti; southern Japan, 103-191 fm.s.); Journ. Wash- 

 ington Acad. Sci., vol. 5, 1915, No. 6, p. 215 (southern Japanese species; range and its significance); 

 Unstalked crinoids of the Siboga-Exped., 1918, p. ix (relationship with A r . clymene), p. 237 (in 

 key; range), p. 239 (synonymy); Smithsonian Misc. Coll., vol. 72, No. 7, 1921, pi. 1, fig. 10 

 (proximal portion). 



Diagnostic features. The centrodorsal is conical with a small dorsal pole; the cirri 

 are not very numerous, XXX-L, with 30-45 (usually 35-40) segments, when the arms 

 are from 40 to 50 mm. long; PI has 8 to 10 smooth, cylindrical segments; the distal 

 borders of the radials and the borders of the elements of the division series are promi- 

 nently everted and finely tubercular or spinous. 



Description. The centrodorsal is conical, low to (usually) more or less elongated, 

 and is almost completely covered with cirrus sockets of which about the periphery 

 there are 3 beneath each radial. 



The cirri are XXX-L, 30-45, from 13 to 15 mm. long; the cirri immediately about 

 the very small dorsal pole are from 3 to 4 mm. long with 12 to 15 segments. In the 

 long peripheral cirri the first segment is short, the second is about as long as broad, the 

 third is about half again as long as broad, and the fourth to ninth or tenth are about twice 

 as long as the greatest (terminal) width; after the tenth the segments gradually decrease 

 in length, the twenty-first being about as long as broad and the last 10 to 16 broader 

 than long. The elongated proximal and middle segments have expanded articulations, 

 this gradually giving way to a somewhat trapezoidal shape, the segments increasing 

 in width from the proximal to the distal end and bearing a slight projection dorsally 

 on the distal end which soon develops into a low spine arising from the entire dorsal 

 surface of the segment. The opposing spine is terminal in position, arising from the 

 entire dorsal surface of the penultimate segment, stout, and not quite so long as tin- 

 width of the segment. The terminal claw is stout, strongly curved, and about as long 

 as the penultimate segment. The apical cirri are very slender and almost filiform \\itli 

 elongated segments and much swollen articulations; there are no dorsal spines, but the 

 opposing spine is well developed. 



The radials are rather prominent and rather strongly concave distally, smooth, 

 or furnished with two, three or four large blunt teeth along their distal borders. The 



are about three times as broad as long, rising in the middle of the distal border 



