MUSEUM OF COMPARATIVE ZOOLOGY. 45 



are small, longer than wide, and broader without than within, where they 

 nearly or quite meet. Under arm-plates much broader than long, pentagonal, 

 with a blunt inner angle, outer edge slightly curved, and laterals re-enteringly 

 curved. Side arm-plates somewhat projecting, nearly meeting below, but well 

 separated above by the thick, broad, somewhat arched upper arm-plates, which 

 are wide fan-shaped, with a blunt angle inward, tkider the microscope they 

 appear minutely tuberculous, while the lower plates are ornamented with wavy 

 'lines. Disk thick and nearly round, completely covered with coarse, rounded 

 granules, 5 or 6 in the length of 1 mm. on the upper surface, and more scattered 

 below. The underlying scales are extremely thin and smooth. Genital open- 

 ings long, exteneling from outer corners of mouth-shield nearly or quite to the 

 margin of disk. Seven long, smooth, cylindrical, tapering arm-spines, the two 

 upper ones as long as three or four arm-joints ; the others somewhat shorter. 

 One long, wide tentacle-scale, with a rounded point occupying the lateral side 

 of the under arm-plate. Color in alcohol, nearly white. 



Station 150, 150 fathoms, 12-fr specimens. Off Prince Edward Isl,, 85-150 

 fathoms, 12-\t specimens. Off Marion Isl., 50-75 fathoms, 12-|7 specimens. 



Ophioconis pulverulenta sp. nov. 



Plate XIV. Figs. 377-379. 



Special Marks. — Disk finely, closely, and evenly granulated, with about 14 

 grains in the length of 1 mm. Eight or nine long, delicate, somewhat flattened 

 arm-spines, the three uppermost longest, and nearly equal. Two tentacle- 

 scales. 



Description of an Individual (Station 172). — Diameter of disk 12 mm. 

 Length of arm about 55 mm. Width of arm close to disk, without spines, 

 3.2 mm. Ten small, short, close-set, pointed mouth-papillae on each side of 

 the mouth-angle, and one somewhat stouter at the apex ; the two outermost 

 are broadest and most rounded. Mouth-shields large, as broad as long, of a 

 rounded heart-shape. Side mouth-shields stout and wide, broader without 

 than within, where they do not meet. Both they and the mouth-shields are 

 more or less covered by a granulation, which, as well as that of the disk, is 

 liable to be rubbed off. Under arm -plates axe-shaped, much broader without, 

 where the edge is curved, and with deep re-entering curves on the lateral sides. 

 Side arm-plates thin and microscopically corrugated. Upper arm-plates thin, 

 with a central ridge, about twice as broad as long, much wider without than 

 within, with sharp outer lateral corners and straight sides. Disk round and quite 

 thick closely and evenly covered with minute granules, 12 or 14 in the length of 

 1 mm. Underneath these granules there are fine uniform, overlapping scales, 

 about 5 in the length of 1 mm., among which the radial shields cannot be dis- 

 tinguished. Eight or nine long, slender, tapering, flattened arm-spines, whereof 

 the three uppermost are about 2.3 mm. long and nearly equal, and the other five 

 or six from 2 mm. to 1.7 mm. long. Two long, thin, nearly oval tentacle-scales, 

 which are two thirds as long as an under arm-plate. Color in alcohol, pale 

 straw. 



