NORTH PACIFIC OPHIURANS IN NATIONAL MUSEUM CLARK. 221 



off southern Japan, lat. 32 36' 30" N. ; long. 132 23' 20" E., 405 to 

 578 fathoms, green-brown mud, fine gray sand, foraminifera, bottom 

 temperature 40.1, 3 specimens; station 4960, off southern Japan, 

 lat. 32 34' N. ; long. 132 21 ' 45" E.. 578 fathoms, green-brown mud, 

 fine gray sand, foraminifera, bottom temperature, 38.7, 1 specimen; 

 station 4976, off eastern Japan, lat. 33 22' 50" N. ; long. 135 38'JM)^' 

 E., 544 to 545 fathoms, brown mud, small stones, bottom tempera- 

 ture 38.7, 1 specimen; station 5080, off Omai Saki Light, lat. 34 10' 

 30" N. ; long. 138 40' E., 505 fathoms, fine gray sand, globigerina, 

 bottom temperature 38.7, 1 specimen. Bathymetrical range, 405 to 

 578 fathoms. Temperature range, 40.1 to 38.7. Seven specimens. 



Type.^C&t. No. 25731, U.S.N.M., from station 4959. 



This is an interesting species for while the figures and description 

 reveal a close relationship to normani and relicta, the general appear- 

 ance is quite different owing to the tumid disk and the slender 

 arms with short spines. Indeed the arms, and particularly the arm 

 spines, are much like those of some species of Ophiolebes. The under 

 arm plates, with the depressions between, also give an impression 

 quite different from that of any of the related species of Ophiacantha. 



OPHIACANTHA LEUCORHABDOTA, new species.a 



Disk 16 mrn. in diameter; arms about 65 mm. long. Disk covered 

 with a sparse coating of very coarse granules, only three to five to the 

 square millimeter; most of the granules are spherical or nearly so 

 but some have minute spinelets on the free end. Radial shields 

 large, bare, near together but not in contact, longer than broad. 

 Upper arm plates rhombic with proximal angle more or less truncate, 

 distal angle rounded and distal sides curved (concave); first one. 

 wider than long, second longer than wide, remainder as wide as long 

 or wider; all more or less in contact. Interbrachial spaces below 

 well covered with granules. Genital slits long but not conspicuous. 

 Oral shield pentagonal with all angles, except proximal, rounded, 

 wider than long. Adoral plates rather large, about as wide without 

 as within where they meet; oral plates moderately large. Oral 

 papillae numerous, five or six on each side and one or more at apex of 

 jaw, long, flat, blunt, the distal one distinctly the largest. First 

 under arm plate longer than wide, narrower distally ; succeeding plates 

 much wider than long, narrower proximally, nearly, if not quite, in 

 contact; they are pentagonal with proximo-lateral sides concave and 

 distal angle rounded, or if this angle is truncated they are of course 

 hexagonal. Side arm plates rather large, not meeting above and 



AeuKOf, signifying white, and papdtordf, signifying striped, in reference to the color of 

 the arms. 



