208 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.51. 



of the Kermaclec Islands, at a depth of 520 fathoms. It differs from 

 Giinther's description in the larger eye, 4 to 4.5, instead of less than 

 5, in head, more than half the postorbital length of head ; in the less 

 sudden constriction of the tail from the trunk ; in the smaller mouth, 

 the maxillaries not extending beyond eye ; and in the distinct serra- 

 tions of the dorsal spine. Giinther's figure shows the ventrals nearly 

 twice as long as the orbit, while they are less than half the orbit in 

 C. rohustus. The Japanese species is also very close to the Atlantic 

 species, C. glohiceps Vaillant,' but differs from a specimen referred 

 to that species from the east coast of South America in the absence 

 of enlarged scales along the anterior base of anal ; in the squamation 

 of the gular membrane, which is naked in the Atlantic specimen ; in 

 the more numerous and much stronger spinules on the scales, espe- 

 cially on the enlarged scales along the dorsal base ; in the absence of 

 an areji with enlarged scales near origin of anal ; and in the more 

 widely spaced scales on the head. Its relationships with the Atlantic 

 species, C. 7nicroi-)s Yaillant,- are unknown. 



Tijpe-specimeTi^-more than 285 mm. long (tip of tail broken), 765 

 mm. to anus ; dredged at a depth of 649 fathoms off the east coast of 

 central Hondo, at Albatross station 4971. Cat. No. 76870. U.S.N.M. 



Dorsal, II, 9 ; ventral, 10 ; pectoral, 17. 



Body robust, very deep, and strongly compressed, especially com- 

 pressed toward the belly. Depth of body over base of ventrals, 1.22 

 in head; under origin of dorsal, 1.3; over fifteenth anal ray, 2.5; at a 

 vertical twice length of head behind tip of snout, 3.9. Width of body 

 over base of pectorals, 3 in head; just behind pectorals, 4.65; width 

 one-third the depth of the slender tail, measured behind the robust 

 anterior portion. Dorsal contour rising in an even curve to origin 

 of first dorsal, the base of which is oblique, the anterior end being 

 higher than the posterior end by a vertical distance half as long as 

 the base of fin. 



Sides of head vertical, without projecting ridges; anterolateral 

 angles of snout prominent, slightly anterior to a vertical from front 

 of premaxillaries, and on a horizontal passing through eye between 

 pupil and upper orbital margin ; distance between lateral angles and 

 eye 1.8 in orbit; distance between lateral angles greater than the 

 interorbital width or the length of the snout, equal to postorbital 

 length of head ; snout broadly triangular in front of lateral angles, 

 its preoral length equal to its preocular length, 3 in head; the tip 

 of snout on a horizontal passing through upper margin of orbit; 

 orbit nearly round, 4 in head, 1.6 in postorbital length; inter- 



1 Maerurus gloMceps Vaillant. in Filhol. La Nature, No. 560, Feb. 23, 1884, p. 199. 

 Hi/menocephalus crassiceps Vaillant, Expert. Sci. du Travailleur et du TaUsman, Pois- 

 )ns, 1888, p. 214, pi. 20. 



Hymenocephalus gloticeps Vaillant, idem., p. 386. 

 2BuU. Mus. Monaco, No. 41, 1905, p. 3; name only. 



