129 
its height from the posterior part. Eye large, by exception 
telescopic. No barbel. Gape of mouth vertical or nearly so. 
Origin of dorsal, which may be preceded by spines, in the 
middle of the body or behind it, above or before that of 
anal. Adipose fin low, totally or partly above hinder part of 
anal, which may be divided. Ventrals small, below or before 
origin of dorsal. Scales absent, if present large, thin and 
exceedingly deciduous. Praeorbital, postorbital and ocular lumi- 
nous organs single. Those on the mandibular symphysis, in the 
branchiostegal membrane and on the body in groups: between 
isthmus and ventrals in a ventral and more lateral series, 
between ventrals and caudal in one series. Body without 
smaller scattered luminous organs. No whitish punctiform 
organs on fins. Small teeth in the jaws, on vomer present or 
absent. Gillmembranes free from isthmus or attached to it, 
they may also be delicately connected. 5—11 branchiostegal 
rays. 4 gills. Gillrakers well developed. Pseudobranchiae present 
or absent. 
Synopsis of the genera. 
A. Body elevated, short, height 11/,. Anal short, 11—17 
rays. Pseudobranchiae present. 
I. Dorsal fin preceded by a forked spine. Teeth 
on vomer. No abrupt ventral constriction between 
trunk and tail. Eyes normal, Anal not divided . Polyipnus p.. 129. 
2. Dorsal fin preceded by a large triangular trans- 
parent plate. No teeth on vomer. An abrupt 
ventral constriction between trunk and tail. 
a. Space between trunk and tail filled by a 
transparent integumentary plate. Eyes normal. 
PSR AMROEROMVIGED <2 wi: vis el els sree coe Sternoptyx p. 132. 
6, Body hatchet-shaped, ventral constriction 
without integumentary plate. Telescopic eyes. 
Fite CIVIMCGh rete te coils var tds ad sy oo eet Argyropelecus p. 134. 
B&, Elongate, not elevated. Height 33/,. Anal long with 
23—24 rays. No pseudobranchiae........... Valenciennellus p. 136. 
1. Polyipnus Giinther. 
(GUNTHER, Challenger Rep. Deep-sea fishes, 1887, p. 170). 
Strongly compressed and elevated, but without abrupt ven- 
tral constriction between trunk and tail, covered with large 
but extremely thin, deciduous scales. Luminous organs before, 
INDO-AUSTRALIAN FISHES II. 9 
