98 BULLETIN 75, UNITED STATES NATIONAL MUSEUM. 



with a short proximal margin; succeeding plates very much wider than 

 long and well separated from each other. Side arm plates rather 

 small, widely separated above, but more or less broadly in contact 

 below, outside of disk; each plate carries two short, sharp, subequal 

 spines, a little longer than half a joint, placed close together, well 

 up on plate, but low down on arm. Oral tentacle pore opening into 

 mouth slit, protected by a very large scale on inner side, and one or 

 two smaller ones on outer side; latter directly continuous with oral 

 papillae; first pore of arm with two or three scales on each side; second 

 with about two scales; succeeding pores each with a single, small, 

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

 or nearly white. 



Localities. Albatross station 3720, off Honshu Island, Japan, 63 

 fathoms, volcanic sand, shells, 1 specimen; station 4893, Eastern Sea, 

 lat. 32 32' N.; long. 128 32' 50" E., 95 to 106 fathoms, gray sand, 

 broken shells, pebbles, bottom temperature 55.9, 3 specimens; 

 station 4900, Eastern Sea, lat. 32 28' 50" N.; long. 128 34' 40" E., 

 139 fathoms, gray sand, broken shells, bottom temperature 52.9, 

 10 specimens; station 4933, Eastern Sea, lat. 30 59' N.; long. 13029' 

 50" E., 152 fathoms, rocky, bottom temperature 56, 5 specimens; 

 station 4934, Eastern Sea, lat. 30 58' 30" N.; long. 130 32' E., 

 103 to 152 fathoms, rocky, 1 specimen. Bathymetrical range, 63 to 

 152 fathoms. Temperature range, 56 to 52.9. Twenty specimens. 



Type. Cat. No. 25718, U.S.N.M., from station 4933. 



This delicate and graceful species seems to be very well character- 

 ized, for while it resembles 0. depressum in many particulars, the oral 

 surface is different, the under arm plates alone being quite sufficient 

 to distinguish the two forms. 



OPHIOCTEN BREVISPINUM, new species, a 



Disk 9 mm. in diameter; arms about 70 mm. long. Disk very thin 

 and flat, notched at base of each arm, interradii being distinctly 

 longer than radii; it is covered by a coat of scales among which pri- 

 mary plates, some large interradial scales and radial shields are 

 prominent ; larger scales and many smaller ones surrounded by belts 

 of minute granules, giving disk a highly ornamental appearance. 

 Radial shields somewhat triangular with rounded corners, longer than 

 wide, nearly in contact distally. Upper arm plates tetragonal, lateral 

 margins somewhat divergent, wider than long at base of arm, but soon 

 becoming longer than wide, broadly in contact, remarkably elevated 

 or swollen at middle of distal margin, more so than in any other 

 species of Opliiocten yet known. Interbrachial spaces below covered 



aJBrevis, signifying short, and spinus, signifying a spine, in reference to the short 

 arm spines. 



