MUSEUM OF COMPARATIVE ZOOLOGY. 81 



they scarcely meet. First under arm-plate broad triangular, or broad rounded 

 hexagonal, with outer edge much curved, and a very blunt angle inward ; 

 second plate nearly sf|uare, with rounded corners ; the next two rudely semi- 

 circular, with outer edge straight, or broad much rounded pentagonal, with an 

 ill-marked angle inward ; the rest are transverse oval, with a peak inward. 

 Side arm-plates wide, a little swollen, meeting below beyond the disk, sepa- 

 rated above by the upper arm-plates, which are much broader than long, 

 with outer edge broken in three angles or curved, and the lateral sides forming 

 an angle. Disk arched, but not thick, covered above and below with small, 

 thin, closely soldered scales, the six primaries being small, circular, widely 

 separated plates. Radial shields much longer than wide, with a sharp angle 

 inward, separated by a wedge of disk-scales; length to breadth 4.5:2. 

 Genital scales very narrow, covered by fine scaling, bearing on their free edge 

 a close row of very fine, square papillae, which increase a little in size as they 

 appear above to form the arm-comb. Three tapering arm-spines, about half 

 as long as a joint ; the upper one the longest. Larger specimens have five or 

 more spines. On the mouth-tentacle pores there are seven or eight close-set, 

 tooth-like scales on either side ; the next two pairs have six or seven on each 

 side, just beyond the disk ; there are four scales on the inner side, and the same 

 numbei- of smaller ones on the outer. Color in alcohol, gray. 



Station 146, 1375 fathoms, 12 + specimens. Station 147, 1600 fathoms, 

 12 + specimens. Station 157, 1950 fathoms, 12 -}- specimens. Station 158, 

 (same species ?) 1800 fathoms, 1 very large specimen. Station 160, 2600 fath- 

 oms, 1 specimen. 



Ophioglypha fraterna sp. nov. 



Plate IV. Fig. 113. 



Special Maries. — Five very minute, blunt arm-spines, which often are 

 rubbed off or naturally wanting. Disb smooth and flat, with scales, radial 

 shields, and mouth-shields all small, and obscured by skin. No arm-comb. 



Description of an Individual (Station 157^. — Diameter of disk 23.5 mm. 

 Width of arm close to disk 3.7 mm. Mouth-papillie short, squarish, closely 

 joined together, seven or eight on each side, diminishing in size inward, with 

 three pointed and longer at apex of jaw. Mouth-shield small, broader than 

 long, pentagonal, with outer edge rounded and obtuse angle within ; length to 

 breadth 3 : 3. Side mouth-shields occupying the inner angle of the mouth- 

 shield, and passing beyond it ; narrower without than within, where they 

 meet. First under arm-j)late much broader than long, with outer edge curved ; 

 second plate six-sided, with inner laterals longest ; beyond the disk they are 

 very broad, triangular, with long sharp lateral angles, an obtuse angle inward, 

 and the outer side cun'ed. Often the lateral corners are broken off, and form 

 separate pieces. Side arm-plates broad, not swollen, meeting below Ix'vond the 

 disk ; separated above by the upper anrt-plates, which are broader than long, 

 and broader without than within, having the outer edge wavy. Disk high and 



