292 Frertp Museum or Natura. History — Zoérocy, Vor. X. - 
Restes guatemalensis Eigenmann & Eigenmann, Proc. U. S. Nat. Mus., 
XIV, 1891, 56. 
Reboides guatemalensis Eigenmann & Eigenmann, Proc. U.S. Nat. Mus., 
XIV, 1891, 57; Jordan & Evermann, Bull. U. S. Nat. Mus., XLVII, 
1896, 338; Regan, Biol. Cent. Amer., Pisces, 1908, 174 (Rio Chagres); 
Evermann & Goldsborough, Proc. Biol. Soc. Wash., XXII, 1909, 
tor (Rio Boqueron; Tabernilla, Atlantic slope, Panama Canal 
Zone). 
Head 3.75 to 4.2; depth 2.65 to 2.95; D. 11; A. 47 to 52; scales 82 to 
89, rarely 80 or 81. 
Body deep, strongly compressed; the dorsal region elevated; profile 
deeply concave over eyes in adult, less so in young; head small; snout 
blunt, 3.34 to 4.5 in head; eye 3.1 to 3.8; interorbital 3.4 to 4.1; mouth 
large; upper jaw projecting; maxillary reaching posterior margin of — 
pupil, 1.85 to 2.25 in head; premaxillary teeth in 3 more or less irregular 
series; the first series composed of 4 conical teeth on outer edge pointed 
directly outward, horn-like; the second series with pointed teeth, the 
anterior ones in advance of lower lip; the third series composed of tri- 
cuspid teeth; maxillary with about 6 small teeth on its inner anterior 
angle and with from 5 to 8 blunt teeth on its outer margin; lower jaw 
with 2 series, the first series with 2 conical teeth on outer margin pointed 
directly forward, the second series anteriorly with 4 tricuspid teeth, 
then with 2 or 3 smaller conical teeth at each side, then a larger tricuspid 
tooth, this one followed by several minute, conical teeth; gill-rakers 
rather short, 8 or 9 on lower limb of first arch; shoulder girdle with a 
sharp spine, reaching base of pectorals; lateral line complete, straight; 
scales small and thin; dorsal fin elevated anteriorly, its origin a little 
nearer tip of adipose than tip of snout; adipose fin well developed, over 
the base of about the eighth anal ray counting from the last ray forward; 
caudal fin naked, the lower lobe the larger; anal fin very long, its origin 
nearer tip of snout than the base of its last ray; ventral fins reaching 
past origin of anal; pectoral fins overlapping the ventrals, not much 
longer than the latter. 
Color greenish brown above, silvery below; a bright silvery lateral 
band in which there is often a short longitudinal black bar under base 
of dorsal. An obscure shoulder spot near upper angle of gill-opening 
usually present; a large black caudal spot; pectorals greenish yellow; 
other fins greenish at base, becoming red at tips. 
Of this species there are numerous specimens in the present collec- 
tion, ranging in length from 40 to 150 mm. It is one of the most com- 
mon fishes in the streams of the Atlantic slope of Panama, occurring 
everywhere from brackish water upward to the mountain streams. 
