FISHES OP ET. SALVADOR 
261 
This fish differs notably in color from the preceding one, but in structure 
the two are very similar. The dorsal fin, however, appears to be inserted slightly 
further backward in the female in the present 
species, usually being an eye's diameter nearer 
the end of the caudal than the tip of the 
snout, instead of being equi-distant or nearer 
the snout. The scales, on an average, possess 
fewer radii in the present species, as shown 
by Figure 16, and in the distal part of the 
intromittent organ of the male, in which only 
one branch of the produced rays bears spurlike 
hooks, while in the preceding species two 
of the branches have hooks. This species 
also appears to be related to Priapichthys 
panamensis, Meek and Hildebrand (Pub., 
Field Mus. Nat. Hist., Vol. X, 1916, p. 322), 
from which it differs in the relative position 
of the dorsal and anal fins, the shape of the 
caudal, and in the shape and structure of 
the produced portion of the anal fin. 
The specimens were obtained in the Rio 
Lempa, at San Marcos and Suchitoto, and 
in brackish water at El Triunfo. 
Family VI. ANABLEPID^ 
Cuatro-ojos 
Body elongate, depressed anteriorly, compressed posteriorly; head broad; 
supraorbital rims much raised ; eye divided into an upper and a lower portion by a 
dark-colored transverse membrane in the cornea; mouth mostly transverse; pre- 
maxillaries protractile; teeth in each jaw in a villiform band; scales small or of 
moderate size ; dorsal and anal fins short ; anal fin of the male modified into a thick 
scaly conical organ with an orifice at its extremit}^. This family consists of a single 
genus. 
9. Genus ANABLEPS Scopoli 
Anableps Scopoli, Introd. Hist. Nat., 1777, 450 (type Cobitis anahleps Linnaeus). 
The characters of the genus are included in the family description. The eye 
in these fish is divided into an upper and a lower half by a dark horizontal partition 
in the cornea. The upper half of the eye is higher than the rest of the head, is 
usually exposed above the surface of the water, and evidently is for seeing in the 
air, while the lower portion is for use in the water. It is from this singular structure 
and function of the eye that the name "Cuatro-ojo," or four-eye, has originated. 
A single species is known from Central American waters. 
i- 
1 
4 
K 
A 
t 
\ — 
Fig. ]6. — Upper figure, Priapichthps fosteri sp. nov.; 
lower figure, Priapichthys letonai sp. nov. Each point 
in the graph is based on the average number of radii on 
three .scales from one specimen. The scales were taken 
below the dorsal fin — one above, one in, and one below 
the lateral line 
