330 THE PLAGIOSTOMIA. 



Raia borea. 



Raia hyperborea Gunther, 1887, Challenger rept. Zool., 22, p. 8, pi. 4. 

 Raia borea Garman, 1899, Mem. M. C. Z., 24, p. 24. 



Disk broader than long, front angle more than 90°, anterior margins undu- 

 lated but not indented, hind margins slightly convex, hind angles broadly 

 rounded, outer angles nearly 90°, rounded. Snout verj^ blunt, length little 

 more than the interorbital width, about equal to the distance between the 

 spiracles. Mouth arched, width nearly equal to the distance from the end of 

 the snout; teeth small, sharp, slender, with narrow bases, widely set. 



Tail shorter than the body, with wide lateral folds, dorsals close together, 

 with or without a spine between them. Back roughened by small stellate- 

 based spines, larger on the rostral ridges and along the front margins. A 

 median series of small tubercles from the head to the dorsals, a row of three or 

 four above each eye and spiracle, and a group of three on each shoulder. Sides 

 of trunk nearly smooth. 



Greyish brown with a trace of a darker spot on each side of the body; white 

 below, uniform on very young, with subsymmetrical blotches of brown on the 

 older. 



Type, a male of 24| inches, taken in the Faroe Channel at a depth of 608 

 fathoms. 



The reasons for separating this species from R. hyperborea will be seen at a 

 glance on comparing the figures of the two as published by Collett and Gunther. 

 The type of R. hyperborea has a long snout like that of R. batis, or that shown, 

 fig, 2, Plate 22; R. borea was figured from a specimen four and a half inches 

 longer, yet it has the shorter snout and its outlines are more like those of fig. 1, 

 Plate 22. Slight differences appear in the squamation. The coloration in 

 both is that of the Raiae of the deep sea. 



Raia hyperborea. 



Raia hyperborea Collett, 1878, Forh. vid. selsk., Chra., no. 14, p. 7; 1880, Norweg. N. Atl. exped., 

 p. 9, pi. 1, f. 1, 2; GooDE & Bean, 1896, Mem. M. C. Z., 22, p. 28, pi. 9, f. 28; Gasman, 1899, 

 Mem. M. C. Z., 24, p. 24. 



Disk broader than long, front angle acute, anterior margins undulated, 

 indented, outer angles nearly 90°, hardly rounded, hind margins almost straight, 

 slightly convex. Snout sharp, length about one and one half times the width 

 of the mouth, or about twice the interorbital width. Mouth arched; teeth 



