226 Proceedings of the Biological Society of Washioigton . 



The upper arm plates are small, fan-shaped, broader than long, in 

 shape and proportions resembling those of 0. granulosa, but entirely, and 

 rather widely, separated from each other. 



The spiniferous ridges on the side arm plates are not continuous 

 dorsally, and are not especially prominent. The arm spines are five in 

 number, rather stout, thickly studded with exceedingly fine short spinules, 

 though appearing smooth to the naked eye. The longest arm spines, the 

 uppermost on the proximal segments, are 2 mm. long. 



The earlier under arm plates are very narrow, longer than broad, with 

 strongly concave sides and a slightly concave distal border ; the distal 

 under arm plates are similar, with a notch in the center of the distal 

 border. 



The tentacle scales are single, rather short, broadly rounded distally. 



Type.— Cat. No. 38,667, U. S. N. M., from "Albatross" Station 5087, 

 ofl southern Japan, in 612 fathoms. 



