47 FISHES OF SINALOA. 419 
not falcate, inserted high, 114 in head, 6 in body, reach- 
ing to the middle of the small ventral. Belly not espe- 
cially compressed, not cultrate. First dorsal very small, 
slightly nearer snout than base of caudal, over first ray ot 
anal; last ray of dorsal much before last of anal. Anal 
very long, somewhat elevated in front, its base 3 times in 
length of body. Soft dorsal and anal scaleless. 
Color translucent green, very pale; back, lips and bases 
of vertical fins faintly dotted; lateral band very broad 
and highly silvery, about two-thirds as broad as eye; 
lower fins pale; air-bladder not visible through the flesh. 
One specimen, 234 inches long. 
63. Thyrina evermanni Jordan & Culver, n. g. and n. sp. 
Plate sxc i 
Common in the estuary. In this species the structure 
of the mouth is exactly as in ZThyrina crystallina. It 
differs from that seen in J/enzdza only in having the upper 
jaw shorter. It is apparently closely related to the genus 
Atherinella of Steindachner, but it has not the toothed 
scales of the type of that genus, Atherinella Panamensts. 
The other characters of A/¢herznel/la—the great length 
of the pectoral fin, the great compression of the breast 
and the long anal fin—are shared by this species which we 
have made the type of a new genus, 7zyrzna. The name 
(@sp:s, window) refers to the translucent sides. Both 
Eurystole and Thyrina are intermediate between JZenzdza 
and Atherinella. 
Thyrina evermanni ditters from Thyrina crystallina in 
the longer anal, the more falcate pectoral, the smaller 
scales, more compressed breast and the absence of black 
on the fins. 
lead “43, ; depth 4% to 53- dorsal Iv, 1, 7; anal I, 
23 tol, 25; scales 36-9; eye 2% in head; snout 33 in 
head; maxillary 3% in head; lower jaw 2% in head; 
