146 DEEP-SEA FISHES OF THE ATLANTIC BASIN. 



examination of their skeletons. The species combined under the name Murwnesox are the 

 only ones known to be certainly possessed of the characters provisionally assigned to the 

 family." (Gill.) 



This family may provisionally receive, in addition to its typical form, a number of 

 genera, chiefly American. They occur chiefly in warm regions. Only three genera are as 

 yet known from the deeper waters, Xenomystax, Hoplunnis, and Sauromurcenesox. 



e> 



XENOMYSTAX, Gilbert. 

 Xenomystax, Gilbert, with Jordan & Davis, Rep. U. S. F. C, 1888 (1891), 648. 



Teeth all conical, slender, and sharp, those of jaws in wide bands; maxillary with 

 deep groove, running the entire length of the bone and dividing the band of teeth into two 

 portions; shaft of vomer with a medial series of conical teeth. 



The genus is represented by a single species, A', atrarius, Gilbert (loc. cit.), from 401 fath- 

 oms off the west coast of Ecuador. 



HOPLUNNIS, Kaup. 



Hoplunnis, Kaot, Aale Hamburg. Museum, 1859, 19 (type H. Schmidtii). — Gunther, Cat. Fish. Brit. Mus., 

 vin, 1870, 49.— Jordan & Davis, loc. cit., 643. 



Mura?nesocids, with scaleless body, with tail about four times as longastrunk. Snout 

 moderately produced. Teeth eight, biserial and small on jaws. Vomerine* with a single 

 series of long-pointed teeth. Dorsal and anal well developed, the origin of the former above 

 the gill opening. Gill opening small. Posterior nostril in front of eyes. 



HOPLUNNIS DIOMEDIANUS, Goode and Bean, u. s. (rigure 163.) 



A Hoplunnis related to H. Schmidti, with height of body one-quarter length of head; 

 its width two-thirds of its height. Snout three to three and two-thirds times eye. Cleft of 

 mouth extends slightly beyond hind margin of eye. Teeth in jaws small, pointed, in narrow 

 bauds, the inner series of the lower jaw consisting of enlarged, widely separated canines. 

 A pair of larger canines near the end of the lower jaw in the example figured. A row of 

 six to eight strong, large canines on the vomer. 



A single individual (No. 44240 U. S. Nat. Mus.) was obtained by the Albatross at sta- 

 tion 2402, 111 fathoms, lat. 28° 36', long. 86° 50'. 



SAUROMURCENESOX, Alcock. 



Sauromurmnesox, Alcock, Ann. and Mag. Nat. Hist., Nov. and Dec, 1889, 457. 



Form of the body widely departing from the typical, the trunk being high and well 

 marked off from the head and tail, which is a long, tapering appendage. Tissues well devel- 

 oped. Gills four, opening into the pharynx by wide slits; gill openings separate. Heart 

 situated immediately behind the gills. Nostrils lateral. Eye large. Tongue free. Verti- 

 cal fins ill developed, confluent ; the dorsal begins in front of the level of the gill opening. 

 Pectoral fins well developed. No scales. Snout long, pointed. Cleft of mouth extending 

 far behind the eye; the upper jaw overlapping the lower. One complete row of teeth in 

 each jaw and a second incomplete row in the maxilla; premaxillary teeth and those at the 

 mandibularly symphysis fang- like; a single row of large fangs in the vomer. 



This genus is represented by one species, S. vorax, Alcock, from Bay of Bengal, taken 

 at the depth of 193 fathoms. 



Family OPHICHTHYID^E. 



Ophichthyida; Gill, Standard Natural History, in, 1885, 107. 



Ophisuridw, Kaup, Cat. Apod., 1856, I.— Jordan & Davis, Eep. U. S. F. C, 1888 (1891), 612. 



Ophichthyoid, apodal fishes, with gill openings rather wide, lateral; scaleless body, and 

 tip of tail sometimes free from vertical fins (sometimes with filamentous caudal fin). Pec- 



