Dec. 28, 1916. FisHes or PANAMA— MEEK AND HILDEBRAND. 367 
Chonophorus tatasica (in part) Jordan & Eigenmann, Proc. U. S. Nat. 
Mus., IX, 1886, 500; Meek, Field Mus. Nat. Hist. Pub., Zodl. 
Ser., X, 1914, 131 (East slope of Costa Rica). 
Chonophorus mexicanus Jordan & Eigenmann, Proc. U. S. Nat. Mus., 
IX, 1886, sor (Eastern slope of Mexico). 
Awaous taiasica Jordan, Proc. Cal. Ac. Sci., 2d Ser., V, 1895, 494 (Presi- 
dio); (in part) Jordan & Evermann, Bull. U. S. Nat. Mus., XLVII, 
1898, 2236. 
Awaous mexicanus Jordan & Evermann, Bull. U.S. Nat. Mus., XLVII, 
1898, 2237. 
Chonophorus banana (in part) Regan, Biol. Cent. Amer., Pisces, 
1905, II. 
Head 3.4 to 3.9; depth 4.75 to 5.55; D. VI-I, 10; A. I, 10; scales 69 
to 76. 
Body anteriorly subcylindrical, posteriorly compressed; head rather 
large, wider than deep; snout long, 2.04 to 2.6 in head; eye small, 5.25 
to 7.5; interorbital 6.25 to 9.7; mouth large, horizontal; upper jaw pro- 
jecting, the lip thickened; maxillary not quite reaching anterior margin 
of eye, 2.5 to 3 in head; teeth small, pointed, in a narrow band in each 
jaw; gill-openings rather small, the membranes broadly attached to 
isthmus; scales small, ctenoid, except the reduced scales on predorsal 
region and abdomen; about 20 rows of scales between anterior rays of 
second dorsal and anal; head and chest mostly naked; origin of first 
dorsal notably nearer snout than base of last ray of second dorsal, the 
spines short and weak, rarely reaching second dorsal; origin of second 
dorsal about midway between posterior margin of eye and base of cau- 
dal, the rays rather short; caudal fin scaly at base, the margin rounded; 
anal fin similar to second dorsal; ventral fins not much longer than snout; 
pectoral fins rather short, 1.3 to 1.73 in head. 
Color yellowish green; back and sides spotted and mottled with 
dark brown; a series of dark blotches along side; sides of head usually 
with a few dark stripes. Dorsals, caudal and sometimes the pectorals 
with dark spots on the rays forming cross-bars; pectorals with a short 
black bar at base of upper rays, running downward and backward; 
anal and ventrals unmarked. 
Of this species we have 48 specimens, ranging from s50 to 215 mm. in 
length. These were taken at various places in the Chagres Basin, but 
always in fresh water, most usually in the lower courses of the streams, 
but a few of them are from the Upper Chagres. 
We have compared specimens from Guatemala and Costa Rica with 
our Panama material and find that the differences between the Pacific 
and Atlantic slope forms as set forth in the above key also are true for 
