416 DEEP-SEA FISHES OF THE ATLANTIC BASIN. 



the length of the snout, its distance from the origin of the ventrals being less than the 

 distance from the origin of the anal, which is distinctly behind the vertical through the 

 posterior end of the first dorsal. 



The ventrals originate under the middle of the first dorsal, and the pectorals under 

 its origin. The ventral extends to, or slightly beyond, the anal origin. The pectoral is as 

 long as the head without its postorbital part. The diameter of the eye is contained 2\ 

 times in the length of the head. The barbel is slightly longer than the eye. The snout is 

 | as long as the head and equal to the iuterorbital space. 



It differs also iu the serratiue of the second dorsal spine, and its length, which is 

 nearly equal to, if not longer than, the head. In our mutilated specimens the first 

 branched ray is nearly as long as the head. The gill-rakers are rudimentary, there being 

 11 below the angle of the arch. 



NEMATONURUS, Gunther. (Figure 3-16.) 



Nematonurus (subgenus), Gunther, Challenger Report, xxn, 124,150. 



Macrurid fishes, with comparatively short, thick, fusiform body; short, globular head; 

 very obtusely rounded snout, and with eye close to profile. Moutli entirely inferior, but 

 not far from tip of snout. Teeth uniserial in the jaws. Branchial opening very wide, the 

 brauchiostegal membrane adhering slightly (in N. gigas) to the isthmus. Head entirely 

 covered with large spinigerous scales, like those upon the body. Muciferous cavities not 

 greatly enlarged. Lateral line originating at a distance from gill opening, usually above 

 it. Pectorals placed medially, below upper angle of gill-cleft. Ventrals stout, with outer 

 ray filamentous. Dorsal origin behind that of pectoral, its longest spine serrated (though 

 but slightly in 2f. gigas). A considerable space between the two dorsals. Second dorsal 

 and anal not very unlike in height, the anal being somewhat further forward. 



Three species appear to belong clearly to this group; N. armatus (Hector), from the 

 South and Middle Pacific, 400-2,425 fathoms (Challenger Eeport, xxn, 150, pi. XL,hg. A); 

 N. affinis (Gunther), from the east coast of South America, 1,900 fathoms; and N~. gigax 

 (Vaillant), from the North Atlantic, 2,082-2,128 fathoms. 



Nematonurus is a thoroughly characteristic bathybial genus. 



NEMATONUKUS GIGAS, (Vaillant), Goode and Bean. 



Coryphanoides giija", Vaillant, Exp. Sei. Travailleur et Talisman, 1888, 232, pi. xx, fig. 2. 



Height of body one-sixth of its length; its thickness one-eighth, being stout, com- 

 paratively short, and, like the head and snout, inflated. Length of head about equal to 

 height of body. Mouth large, interior, under the eye. Teeth in jaws in a single row, 

 simple, conical, about 20 to 25 on each side of either jaw. Eye close to profile, its diameter 

 one-fifth the length of the head, and a little less than width of interorbital space, which is 

 one-fourth of head. Length of barbel equal to diameter of eye, which is about equal to the 

 length of the snout. Scales strongly spinigerous, with spines arranged in radiating rows. 

 Nme above and thirty-four rows below lateral line, which contains 138 scales. Head 

 covered with rough scales like those on the body. Limb of preoperculum concave. 



First dorsal placed comparatively far bade, without elevation of the dorsal outline at 

 its base; its second spine almost smooth, but with a lew rugosities near its tip; its height 

 equal to about half that of the body. Distance of second dorsal from first equal to Hi times 

 the length of the base of the latter and a little less than the length of the head. Origin of 

 anal nearly under middle of interspace between dorsals. Its height similar to that of 

 second dorsal. Pectorals rather strong, with outer ray somewhat produced. Ventrals 

 slightly behind root of pectoral, far in front of origin of dorsal, rather strong, with outer 

 ray produced. 



Color gray; brauchiostegal membrane and fins brownish. 



D. 10 + 87; A. 107; V. 10. 



Two specimens were obtained by the French expedition between the Azores and the 

 Trench coast in f,Lo5 and 4,255 meters. 



