za 
THE CYPRINODONTS. 99 
B. 5 (rarely 6); D. 11-13; A. 10-12; V.6; P. 17-19; Vert. 14-15+ 
19-20. 
Moderately stout, compressed posteriorly, depressed on the head; arch 
from head to dorsal rather low; depth in front of dorsal equal length of 
head, or one half more than depth of caudal pedicel. Head two sevenths of 
the length to the base of the caudal,as broad as deep, flattened on the crown. 
Snout as long as eye, blunt, rounded ; chin convex, moderately steep. Mouth 
nearly twice as wide as eye. Teeth conical, in bands, outer series larger ; 
pharyngeal with a shoulder, some of the median larger, compressed, swollen. 
Eye medium, once in snout, twice in interorbital space, four and a half times 
in the head. Cheek scales in three rows below the orbit. Dorsal and anal 
little behind the middle of the total length ; dorsal origin midway from head 
to base of caudal; fin not reaching as far backward as the anal. Base of 
anal opposed to that of dorsal, hardly reaching as far either forward or back- 
ward as that of dorsal. Fins comparatively large and broad, varying with 
age and sex. Caudal deep, subtruncate to rounded. Pectorals wide, short, 
rounded, reaching a vertical from the bases of the ventrals. Scales large, 
striate. Oviduct adherent for some distance along the first ray of the anal. 
Intestine as long as the fish. A few individuals have six branchiostegal rays 
instead of five. } 
Males are most often olivaceous, darker on the back, lighter to white or 
silvery beneath, with a dozen or more narrow vertical bars of light color 
across the flanks, and with a black spot edged with white on the hind rays 
of the dorsal. Fins and body are more or less marked with small spots, 
bars, or dots of dark and of light colors, A black spot sometimes present on 
the hind rays of the anal; and not rarely the hind margins of dorsal, anal, 
and caudal are whitish. On some individuals of this sex the colors are more 
like those of the females, Southward the silvery spots and dots are more 
distinct on body and fins, As in the salmon and trout the silver color is 
more prevalent in salt-water specimens, and no doubt fresh-water examples 
change on entering the sea. 
Females are not so brightly colored as males; some are nearly uniform 
brownish on the backs, lighter below, with a darker spot on each scale ; others 
have vertical bars or spots of brownish on the flanks. The vertical silvery 
streaks are frequently met with, but less distinct. In cases a silvery tint 
extends the length of the body on the middle of the side. The spot on 
the dorsal is rarely present on the female. Generally the lower half of the 
