608 
BULLETIN OF THE UNITED STATES FISH COMMISSION. 
Body elongate, compressed, deepest at nape, thence tapering gently to the very narrow caudal 
peduncle; head long, posteriorly compressed; snout long and sharp; eye in posterior half of head, its 
vertical diameter exceeding the horizontal diameter; interorbital space and occiput nearly flat; a pair 
of low ridges above each orbit; mandible included within margins of upper jaw, the latter transversely 
arched to receive it; the rounded end of mandible upturned to fit into an emargination of the pre- 
maxillaries; premaxillaries narrow, closely apposed to maxillaries, which fail to reach the vertical 
from front of eye; about half the width of the narrow maxillary for its entire length slips under the 
free margin of the preorbital, which continues as a conspicuous fold to below front of eye; upper 
jaw nonprotractile; the anterior arched portion of the premaxillaries toothless; near the front, on each 
side, is a long, depressible canine, preceded by a much smaller depressible tooth; behind these, after 
a short toothless interval, is a single series of short, fixed, bramble-like teeth, hooked backward, 
growing minute toward angle of mouth; all of the premaxillary teeth shut outside the mandible; 
mandibular teeth in 2 series, an outer row of short, fixed teeth and an equal number of inner, long, 
fang-like canines, which are depressible; the canines are widely spaced, about 8 in number on each 
side; palatine teeth similar, arranged in about 5 pairs, each consisting of an outer, short, fixed tooth 
and an inner, depressible fang, the middle fangs on each side a little the longest; vomer toothless; on 
each side of middle of tongue a lengthwise series of small, depressible teeth hooked backward; anterior 
nostril very small, closed from in front by a short, triangular flap; it is placed high and is distant from 
eye 0.3 the length of snout; posterior nostril a horizontal slit midway between anterior nostril and eye, 
and slightly above middle of orbit; gills 4 in number, with a slit behind fourth arch; gill-rakers 
represented by series of short, sharp spines on each arch; pseudobranchiae well developed, occupying 
a pocket made by a fold of the membranous lining of the cheek and a ligamentous band from upper 
end of outer gill-arch; subocular photophore small, but well developed. 
Fig. 236 . — Lestidium nudum Gilbert, new species. Type. 
Upper margin of pectoral but little below axis of body; longest rays two-fifths length of head; 
ventrals inserted midway between base of caudal and front of posterior nostril; front of dorsal well 
behind insertion of ventrals, behind middle of trunk a distance equaling half diameter of pupil; 
caudal forked, its lower lobe recurrent along lower line of caudal peduncle, with well-developed rays 
which reach to base of anal ; vent overlapped by the short ventral fins, and distant from front of anal 
a distance about equaling length of anal base; adipose fin small, inserted above last anal rays. 
The type was in perfect condition when taken, and showed no trace of scales or scale-pouches on 
the head or body. The lateral line is a wide tube, inclosed by a series of small scales which are 
wholly embedded and concealed. It does not open through tubes which penetrate the scales, but 
through minute pores occurring in groups of 3, above and below the scales. Posteriorly the scales 
diminish in size, and disappear, together with the lateral tube, opposite middle of anal fin. 
Color translucent, with faint silvery luster; back a little darker; a Y-shaped blackish mark on 
occiput and nape; sides of snout and gill-membranes blackish; opercles largely bright silvery; a 
narrow black crescent around upper and lower contours of eye-ball; a narrow silvery streak anteriorly 
on each side of median line of abdomen, each streak with an inner line of coarse black specks; 
caudal peduncle washed with blackish and silvery, this area extending forward to middle of anal, but 
leaving a narrow translucent area above and below it; peritoneum and lining of opercles largely black; 
fins largely translucent; caudal a little dusky; anterior anal rays black-punctate at base; ventrals 
each with a small black basal spot. 
Only the type specimen known; possibly captured by the trawl near the surface. 
