NORTH PACIFIC OPHIURANS IN NATIONAL MUSEtJM CLARK. 245 



OPHIOLEBES DIAPHORA, new species.a 



Disk 11 mm. in diameter; arms about 35 mm. long. Disk covered 

 by thick, rounded plates of variable size, upon and among which are 

 scattered numerous coarse, rounded granules, which are largest 

 around the radial shields. Radial shields large, oval, widely sep- 

 arated from each other. Upper arm plates rhombic, about as long 

 as wide. Interbrachial spaces below covered by rounded plates and 

 granules like those of disk. Genital slits inconspicuous. Oral 

 shields very small, rounded pentagonal, about as long as wide. 

 Adoral plates twice as long as wide; oral plates moderate; all of 

 these plates about the mouth 

 are indistinct, due to the 

 skin which covers them. 

 Oral papillae four on a side 

 and one at apex of jaw; 

 thick and rounded, or 

 pointed at tip; outermost 

 papilla much the largest. 

 First under arm plate 

 small, thick, squarish, or 

 rounded; succeeding plates 

 thick and swollen and poorly 

 defined, on account of the 

 skin covering. They seem 

 to be wider than long, but 

 their exact shape is hard to 

 determine; all but the first 

 two seem to be separated 

 from each other. Side arm 

 plates moderate, meeting 

 slightly above but not below, 

 somewhat thick and swol- 

 len. Each plate carries five 

 to seven short, thick, blunt 

 spines, of which the up- 

 permost or next lower is longest and equals a joint and a half; 

 lower spines short and very stout, with rough, prickly tips; lowest 

 spine may be almost spherical. Tentacle pores small; tentacle scale 

 single, large, rounded, but rough at tip. Color (dried from alcohol), 

 yellowish or yellowish-brown. 



Localities. Albatross station 3599, Bering Sea, lat. 52 5' N.; long. 

 177 40' E., 55 fathoms, rocky, fine sand, shells, 4 specimens; station 

 4779, Bering Sea, lat. 52 II' N. ; long. 179 57' W., 54 to 56 fathoms, 



C 



FIG. 118. OPHIOLEBES DIAPHORA. X 4.5. a, FROM ABOVE; 

 b, FROM BELOW; c, SIDE VIEW OF TWO ARM JOINTS NEAR 

 DISK. 



a Aca(f)opo, signifying different. 



