540 Bulletin 4J, United States National Museum. 



vomer. Insertion of dorsal behind snout at a distance a little more than 

 its own base and about \ the total length, longest ray equal to great- 

 est depth of body. No adipose dorsal (in the specimens known); anal 

 inserted considerably behind last ray of dorsal, its base about half that of 

 the dorsal ; ventrals well apart, inserted just in front of the dorsal, their 

 length half head; pectoral as long as lower jaw, its seventh ray pro- 

 longed to a length equal to that of head; caudal slightly forked ; scales 

 thin, cycloid, deciduous, those of the lateral line larger, brownish ; lining 

 of gill cavity blue-black. Atlantic and South Pacihc, known from off 

 New Zealand, Morocco, and the Gulf Stream if, as supposed, the American 

 B, agassizii is identical with B.ferox. (Goodo & Bean. ) (ferox, ferocious. ) 



Ilathi/saurus feroj-, GrxTHEK, Aun. Mag. Nat. Hist., 1878, 182, east coast of New Zealand. 

 Ballii/smirtis cuiiisshii, GoODE & BbaNjIJuII. Mils. Com]). ZoLil., 1882, 215, Gulf Stream, 33° N. in 

 647 fathoms; Goode & Bean', Oceanic Ichth., 58, 1895. 



250. BATHYLACO, Goode & Bean. 



Baihylaco, GooDE & Bean, Oceanic Ich'thyology, 57, 1895, {uitjricans). 



Body subcylindrical, rather elongate, stout, similar in form to Synodua. 

 (Scales absent in the specimen studied, and it is not even possible to 

 determine whether or not this is a naked species.) Head conical ; snout 

 short. Mouth very large, wide, oblique, lower jaw slightly projecting. 

 Premaxillary narrow and long, with small teeth, which are somewhat 

 biserial in front and uniserial behind, interrupted at the symphysis. 

 Mandible with a narrow band of similar teeth; palatine teeth in a nar- 

 row band ; tongue toothless. Eye moderately large, very far forward, its 

 upper edge close to the dorsal profile. Pectoral small, placed low ; ven- 

 tral nearly median, a little in advance of the dorsal and far behind the 

 pectoral, with 8 rays ; dorsal origin nearly in the middle of the length 

 and extending to above the middle of the anal ; adipose fin probably 

 absent ; anal origin far back, fin short. Gill opening very wide, as 

 in Batliysaurus, the left membrane overlapping the right, not attached to 

 the isthmus. Branchiostegals numerous. Gill rakers short and few. 

 Opercular bones very thin and feeble. Deep sea. (/3a^/f, deep; A(i«wof, a 

 hole or pit.^l 



SI 7. B.4THTLAC0 XKJBICAXS, Goode & Bean. 



Head 4 ; depth 2; eye -li in head, equal to interorbital width. B. 8; D. 

 20 ; A. 10 ; V. 8 ; P. 6. Snout about 2 in eye and about 8 in head. The 

 lower jaw the longer. The intermaxillary is nearly f length of head. 

 The mandible is contained 3 times in distance from tip of snout to origin 

 of dorsal ; dorsal fin inserted at a distance from the tip of the snout equal 

 to twice length of head, the length of its base nearly i of total (without 

 caudal) ; origin of anal under posterior third of dorsal, the length of its 

 base equal to half that of head ; pectoral small, placed low, immediately 

 back of the branchial opening; apparently few-rayed. Color black. 



A single specimen in very bad condition, 8i inches in length, taken by 

 the Blake oft' Santa Cruz, at a depth of 2,393 fathoms. (Goode & Bean.) 

 {nUjricans, blackish.) 



Bathylacn nigricans, Goode & Bean, Oceanic Ichthjology, 57, fig. 60, 1895, off Sai.ta Cruz, 

 Mexico, 



