56 BULLETIN 100, UNITED STATES NATIONAL MUSEUM 
Alcock,® but differs in the more posterior insertion of the dorsal, which 
is midway between the pectoral origin and the caudal base. 
Type—U.S.N.M. No. 99512. D. 5495. Diuata Point (N.), N. 76° 
E., 9.4 miles (lat. 9°06’80’’ N., long. 125°00’20” E.), between Leyte 
and Mindanao. In 976 fathoms. August 2, 1909. No. 4460. Length 
147 mm. 
(retropinna, backward fin.) 
Family IPNOPIDAE 
IPNOCEPS, new genus 
Type.—I pnoceps pristibrachium, new species. 
Differs from /pnops chiefly in the uppermost or simple pectoral ray 
with its upper edge dentated or irregularly serrated. The anal fin 
base is greatly longer than shown by Giinther and by Goode and Bean 
for the Atlantic Jpnops murrayi. The longer pectoral also reaches 
nearer to level with the dorsal origin in the vertical in /pnoceps. 
The luminous superocephalic organ is also broader in Ipnoceps. ‘The 
fins, proportions, and scales all differ from those of Jpnops. 
One species in the western Pacific. 
(urvés, lantern-+xepadn, head.) 
IPNOCEPS PRISTIBRACHIUM, new species 
FIGURE 6 
Depth 1114; head 414, width 134. Snout broadly arched as viewed 
from above; large luminous cephalic organ broad as long; maxillary 
reaches halfway in head, expansion 7 in head; mandible 114; mouth 
but little inclined from horizontal, with mandible well protruded in 
front. Gill opening large, well extended forward to about first sixth 
in head. 
Scales 47-+-1 in axial lateral series; 8 transversely below dorsal 
origin; 21 predorsal; 3 large scales between origins of ventrals; 4 
scales transversely on side of caudal peduncle. 
D. 1, 9, 1, first branched ray 114 in total head length; A. nm, 18, 1, 
third ray 2; caudal subequal with head, convex behind; pectoral rays 
1, 12, fin 114 in head; ventral 114, rays 1, 7. 
Color in alcohol uniform black. Luminous cephalic organ pearl- 
white. Pale or light streaks along each side of predorsal squama- 
tion down to pectoral base. 
The distinctive characters are contained largely in the generic 
account above. 
Type.—U.S.N.M. No. 99508. D.5607. Binang Unang Island (E.) 
S. 36° E., 5 miles (lat. 00°04’00” S., long. 121°36’00”" E.), Gulf of 
5 Catalogue of deep-sea fishes obtained by the Investigator, p. 180, pl. 32, fig. 3, 1899 
(type). 
