606 
BULLETIN OF THE UNITED STATES FISH COMMISSION. 
Length to base of caudal 66 mm. Of this length the head forms 22 hundredths; diameter of orbit 
4; bony interorbital width 4; length of snout 6; mouth measured from tip of snout to end of maxil- 
lary, 18; length of barbel 30; greatest depth of body 15; least depth of caudal peduncle 6; distance 
from tip of snout to base of dorsal 52; length of dorsal base 13; distance between dorsals 16; from front 
of adipose dorsal to base of middle caudal rays 21; distance from tip of snout to base of ventrals 48; 
length of anal base 15; distance between the lower adipose fin and the anal 7.5; length of ventrals 21; 
length of pectorals 18; height of dorsal 19. D. 12, the first ray very short, the last split to the base; A. 
19; P. 6; V. 7. 
Interorbital width equaling diameter of orbit, rather strongly grooved, and bounded on each side 
by 2 sharp ridges, which are closely apposed over the middle of the orbit and diverge forward and 
backward from this point; a minute bluntish protuberance at the upper posterior margin of the orbit, 
and behind this a third ridge, outside the 2 which bound the interorbital area; mandible massive, 
slightly protruding beyond premaxillaries; teeth notably smaller than those figured by Lutken (Spolia 
Atlantica, Scopelini, pi. 3, fig. 7) from Klunzinger’s type of A. martensii. Near tip of mandible a very 
long slender canine, double on one side in the type, single on the other; nearer the symphysis a second 
pair, no longer than the shortest teeth on sides of mandible; teeth on one side of the mandible sub- 
equal and arranged regularly in pairs, one pair near the outer margin of the jaw alternating with 
another nearer its inner margin; posteriorly where overlapped by the maxillary, a few small teeth 
only, in line with those of inner row; arrangement less regular on the other side of the mandible, some 
of the teeth apparently fallen; two pairs of canines in front of premaxillaries, the inner pair not half 
the length of the outer; sides of premaxillaries with a few small canines like those in the mandible, 
apparently also arranged typically in pairs, though this is less evident; most of the canines slenderly 
arrow-shaped at tip ; maxillary forming a trifle less than half margin of upper jaw and ending posteriorly 
in a short spine; it bears a single row of 15 to 20 very slender, close-set teeth, directed obliquely down- 
ward and backward; a single minute tooth on each side of the head of the vomer,- a series of similar 
teeth on palatines; no teeth on tongue; gill-rakers represented by short spinous teeth arranged in pairs, 
of which 12 are present on the horizontal limb of the outer arch; barbel longer than head, with a dilated 
tip, reaching about to middle of pectorals. 
Dorsal more anteriorly inserted than in A. martensii, its insertion midway between nostril and 
base of caudal, slightly behind insertion of. ventrals; ventrals midway between end of maxillary and 
front of anal; when declined, the ventrals reach slightly beyond pre-anal adipose fin; front of adipose 
dorsal over fourth or fifth anal ray, thus far in advance of middle of fin; pectorals extending over two- 
thirds their distance from ventrals. 
In color this species agrees with A. martensii, being grayish silvery on sides of head and body, 
brownish black above, black on under parts; fins translucent, unmarked. 
The photophores show a similar arrangement: Operculars 2. Branchiostegals 18, one for each 
ray. Jugulars 8, along the sides of the isthmus. Thoracics 22, 4 of these in advance of axils of 
pectorals. The jugulars and thoracics form continuous series, the 2 parallel anteriorly, strongly 
diverging posteriorly to reach the bases of the ventrals. Ventrals 22, the anterior 2 pairs in advance of 
the ventrals, between the diverging ends of the thoracic , series. Anals 2+8, a wider interspace 
between the second and third; the last 2 are smaller than the others and diverge upward in a curved 
line. Caudals 4. The subocular photophore is shorter and rounder than in Liitken’s figure, and is 
farther back, none of it under the pupil; its posterior end is much nearer the eye than the maxillary. 
The entire body is covered with minute pores, which appear black on the silvery portions, light on 
the blackish areas, and are arranged in more or less regular cross series. 
A single cotype was obtained at station 3918, off the south coast of Oahu, depth 257-294 fathoms. 
Family STOMIID^E. 
Leptostomias, new genus. 
Body extremely elongate, but little compressed, without scales; mouth very wide; anterior teeth 
slender, fang-like, unequal, projecting outside jaws in closed mouth; a pair of slender teeth on vomer, 
a similar tooth on each palatine and a pair on tongue; branchiostegal rays 17; no pseudobranchise; eye 
very small; pectoral without detached ray; ventials inferior, far behind middle of length; dorsal and 
