DISCUSSION OF SPECIES AND THEIR DISTRIBUTION. 45 



cave between the orbits, with a convexity above the snout. Width of the interorbital space 

 about equal to the diameter of the eye. Tlie length of the snout contained 85 times in that 

 of the head. Eye large, a little longer than deep, contained 4g times in the length of the 

 head and IJ times in the length of the snout. Infraorbital ring very narrow. The maxil- 

 lary is bi-oad, large, and conspicuon.sly dilated at the extremity, its greatest width at this 

 point being more than two-thirds the diameter of the eye. Cleft of the mouth wide. Den- 

 tition fee))k'; no traces of teeth upon either vomer or palatine." Branchiostegals 5, long 

 and slender. Gills 4. Gill lamin.B short, especially on the convex portion of the arches. 

 Gill rakers long, strong, broad at the base; 6+17 on the outer arch. 



Vent placed equidistant from root of caudnl and root of pectoral. The oiigin of the dorsal 

 over the vent; slightly in advance of that of the anal. Dorsal tin longer than high, its 

 anterior rays increasing in length to the middle of the fin, the longest ray contained 3| in 

 length of head, and about equal to the longest ray of the anal. Caudal tin deeply emargi- 

 nate. Pectoral inserted far below the middle of the body. It has a narrow base, and its 

 length in a perfect specimen is probably not greater than the diameter of the eye. Ventrals 

 close together, remote from the vent, the root being nearly midway between the root of the 

 caudal and the tip of the snout, and equidistant from the root of the anal and the base of 

 the pectoral. 



Scales deciduous, cycloid, 45 or 48 in the lateral line, the lateral line beginning from a 

 point on a level with the top of the eye, and ascending in a broad curve to a point over the 

 ventrals, and thence in a straight line to the root of the caudal. Color, bluish black. 



Eadial formula: B. o (!); D. 22; A. 21; V. 7; P. 8. 



A single specimen, 14J inches in length, was obtained by the Fish Commission steamer 

 Albatross, from station 2793, Lat. 01° ((3' N., Ion. 80° 15' W., in 741 fathoms. 



BATHYTROCTES ATTRITUS, Vaillant. 



B<itltiilroch-s aUritus, Vaillant, Exp. Sci. Travailleur et Talismuu, Poissous, 1888, 158, pi. xil, fig. 2 (struc- 

 tural details). 



This name was given by Vaillant to certain mutilated fishes obtained from the Azores, 

 Cape Verde, and Banc d'Arguin, at 1,550 to 3,G55 metres If they belong to Baihytroctes at 

 all, they appear to resemble most closely B. melanocephalus. Until fresh material shall be 

 obtained, it seems doubtful whether B. attritus is a valid species. 



NARCETES, Alcock. 



Narcetes, Alcock, Ann. and Mag. Nat. Hist., 1890, 11, 305, vii, 1891, i, 10. 



Body, as in Baihytroctes, rather elongate, compressed, covered with scales of moderate 

 size. Bye rather small. Cleft of mouth wide, the maxillary extending beyond the vertical 

 through the middle of the eye. Teeth in premaxillary and mandible fine, j)/Hmf'r««i; fine 

 teetli on maxillary, palatines and vomer; no teeth on tongue. Dorsal and anal fins rather 

 short, the fin-mer beginning in vertical from origin of ventral. No adipose dorsal. Caudal 

 symmetrically forked. Gill openings wide. Pseudobranchiie present. Gill rakers com- 

 plete; 7 branchiostegals; 4 gills, with narrow lamina'. Gill rakers long. Pyloric append- 

 ages in moderate number. 



The type of this genus is Narcetes eremilas, Alcock (1. c.), obtained by the Investigator 

 in the Arabian Sea (station 105) at a depth of 740 fathoms. The description is based upon 

 two female specimens, measuring 13A and (U inches respectively. 



PLATYTROCTES, Gunther. 



Platytroctes, GiJNTHEK, Ann. and Mag. Nat. Hist., 1878, 11, 249; Challenger Report, xxii, 229. 



Body rather abbreviated, much compressed, and covered with small keeled scales. 

 Mouth of moderate width; the maxillary and intermaxillary and mandible armed with a 

 single series of small teeth. Palate smooth. Eye rather large. The dorsal and anal tins 



' This may be due to the condition of the specimen. Should it be a good character it may necessitate the 

 formation of another subgenus. 



