49 FISHES OF SINALOA. 421 
Head 434; depth 4% to 5; dorsal IV-I, 8; anal I, 
21; scales 40-11; pectoral } longer than head, 4% in 
body; anal base more than half longer than head, 3 in 
body. eye 23, “im head; snout, 3% ; maxillary 27, ; 
lower jaw 2%. 
Body rather deep and compressed; snout shortish; 
opercle shortish, rounded behind; mouth small, the upper 
jaw very protractile, the premaxillary strongly curved: 
jaws equal; teeth rather strong, the outer curved, those 
in upper jaw largest; eyes very large, silvery; breast 
compressed, as in Thyrzna evermannt, but less sharp at 
edge, appearing as if pinched between thumb and finger; 
pectoral long, pointed, not truly falcate, reaching more or 
less past the middle of the short ventrals, its posterior 
margin not concave, the middle rays considerably more 
than half length of upper rays; dorsal and anal naked; 
gill-rakers numerous, long and slender; first dorsal small, 
behind front of the long anal, midway between gill open- 
ing and base of caudal; first ray of soft dorsal over about 
fourth of anal; last rays of soft dorsal considerably be- 
fore last of anal. Caudal lunate, the lower lobe the 
longer and broader, as long as head. Color, translucent 
green, with considerable dusky dottings, no yellow; fins 
dotted; ventrals black, as are lobes of second dorsal and 
anal; silvery stripe narrow, little more than half diameter 
of the eye; first dorsal and base of anal dusky; air- 
bladder evident through the translucent sides of body, 
but less clearly so than in 7hyrina evermannz. 
In fresh water, very common in the lower Presidio; 
many specimens taken; the longest 3% inches long. 
ype, INO.) 2685, d2...9..)r--Univ.. Mus. 
