NORTH PACIFIC OPHIURANS IN NATIONAL MUSEUM CLARK. 99 



by about twenty-two large scales, with numerous granules along mar- 

 gin and near genital slits. Oral shields small, pentagonal, usually 

 wider than long. Adoral and oral plates rather large, each with 

 a few granules. Oral papillae about five on a side, outer ones trun- 

 cate, inner ones pointed. Genital slits short; genital scales rather 

 large, but without marginal papilla? ; no trace of an arm comb. First 

 two under arm plates longer than wide; next three about as long as 

 wide ; succeeding plates wider than long ; plates not in contact beyond 

 disk; first plate hexagonal, succeeding plates tetragonal, becoming 

 triangular, with outer corners rounded. Side arm plates rather small, 

 not meeting above, but meeting below beyond disk; each plate carries 

 two short, thick, pointed spines less than half as long as joint, placed 

 close together, high up on plate but low down on arm. Oral tentacle 

 pore concealed by a huge lid-like scale on its outer side ; first arm pore 

 with one low, wide scale or two smaller scales on each side; second 



FIG. 36. OPHIOCTEN BREVISPINUM. X5.5. a, FROM ABOVE; 6, FROM BELOW; c, SIDE VIEW OF THREE 



ARM JOINTS NEAR DISK. 



pore with two small scales; succeeding pores with only a single small, 

 round scale. Color (dried from alcohol), pale gray. 



Localities. Albatross station 4917, Eastern Sea, lat. 30 24' N.; 

 long. 129 6' E., 361 fathoms, gray sand, globigerina, broken shells, 2 

 specimens. 



Type. Cat. No. 25617, U.S.N.M., from station 4917. 



Although the general appearance of this species is similar to that of 

 charischema, the granulation of the disk is entirely different in the two 

 species, and the huge oral tentacle scales, the short arm spines, and 

 the decidedly " humped" upper arm plates make brevispinum very 

 easy to recognize. 



OPHIOCTEN OOPLAX, new species, a 



Disk 10 mm. in diameter; arms about 65 mm. long. Disk flat, 

 nearly circular, covered by several hundred overlapping scales, small- 

 est near center of disk, largest between radial shields. Radial shields 



a'Qov signifying egg, and 7rM, signifying plate, in reference to the oval upper arm 

 plates. 



