80 
BULLETIN OF THE BUREAU OF FISHERIES 
Specimens 7 to 8 millimeters long . — No pronounced changes in the proportions 
of the body have taken place since a length of about 4.5 to 5.5 millimeters was attained. 
The distance from the snout to the vent is contained 2.0 to 2.2 times in the length 
to the base of caudal; distance from vent to base of caudal 1.8 to 2.1 times; and the 
greatest depth 2.65 to 2.8 times. A slight concavity remains in the ventral outline 
of the body between the vent and origin of anal, which is occupied by a thin mem- 
brane, apparently a remanent of the finfold. Above this concavity in the ventral 
outline, the body is very thin and semitransparent. The snout remains short and 
narrow, its length being equal to the diameter of eye, and the profile ascends abruptly 
from its tip. Considerable advancement has been made in the development of the 
fins. The spinous dorsal is fairly well differentiated, although rather more closely 
connected with the soft dorsal than in the adult. About 12 spines and 24 soft rays 
may be counted. The anal fin consists definitely of 2 spines and 7 or 8 soft rays. 
The caudal fin is frayed in the specimens at hand, but it evidently is long and pointed. 
The ventral fins remain small. The dark markings present vary in size and number 
among specimens. Generally a few dark dots are present on the median line of the 
chest and abdomen. The spot at the end of base of anal, present in all the smaller 
larvae at hand, persists. Some specimens now have two spots at and behind the anal 
base, and each one may have a narrow vertical projection. Some specimens also 
have a small black spot near the origin of the anal. A rather prominent dark spot 
is present above the vent, which often is more or less connected with other spots, 
reaching to an elongate, finely branched shoulder spot. A narrow dark bar at the 
base of the caudal is evident (fig. 23). 
Specimens 10 to 13 millimeters long . — The proportions of the body remain about 
as in somewhat smaller specimens. The distance from the snout to the vent is 
contained 1.85 to 2.0 times in the length to the base of the caudal fin, distance from 
vent to base of caudal 2.05 to 2.15 times, and the greatest depth 2.6 to 2.75 times. 
A slight concavity remains evident in the ventral outline between the vent and the 
origin of the anal (which is occupied by a thin membrane as in smaller fish), and the 
distance between these two points exceeds the diameter of the eye. The snout has 
become broader and rounder; the mouth is less oblique and wholly below the lower 
margin of the eye ; and the maxillary reaches nearly or quite to the posterior margin 
of the eye. In all the characters about the head, just mentioned, the fish is approach- 
ing the shape and form of the adult. The eye is unusually small. The cavernous 
nature of the skull, with its bony ridges, is quite prominent. The preopercular spines 
are smaller and more numerous than in younger fish. The fins are all well developed, 
the dorsal formula is X or XI-I, 23 or 24, and that of the anal II, 7 or 8. The caudal 
remains long and pointed, the longest rays being longer than the head. Little 
