1528 Bulletin //, United States National Museum. 



aaaa. Anal spines 5, rarely or never 6 ; dorsal rays XVI, 11 or 12. 



j. Body rather elongate, the depth 2f in length ; scales 32. PAVONACEUS, 1945. 



jj. Body moderately deep, the depth 2| in length; body with cross bands and 



pearly dots. ALTIFRONS, 1946. 



jjj. Body deep, the depth 2f in length ; scales 30 ; coloration nearly plain, the 



fins with dark spots. BEANI, 1947. 



aaaaa. Anal spines normally 4 (very rarely 5). Dorsal rays XV or XVI, 10 to 12; body 



rather deep, compressed, the depth 2 in length; body and fins with dark- 



brown spots. TETRA.CANTHUS, 1948. 



1924. HEROS FRIEDRICHSTHALI, Heckel. 



Head 2f ; depth 2^; eye 3| in head, equal to snout. D. XVIII, 9 or 10; 

 A. VIII or IX, 9 or 7 ; scales 4-31-12. Fold of lower lip continuous in 

 middle. Scales on cheek in 7 series. Antero-inferior margin of preorbi- 

 tal concave, the greatest width of this bone only ^ that of orbit. Length 

 of twelfth dorsal spine f- that of head. Longest dorsal ray 1^ in head ; 

 longest anal ray 1^ in head. Yellowish olive, with 6 or 7 blackish cross 

 bands;* a black band from eye to upper part of root of caudal, inter- 

 rupted by the interspaces between cross bands, the origin and end of this 

 band are edged with yellow; suboperculum with a black ocellus; an 

 oblique black streak from eye toward ocellus. Length 5 inches. Lake 

 Peten, Lake Nicaragua, and its outlet, the Rio San Juan. 



Heros friedrichtthali, HECKEL, Flussftsche Brasil, 381, 1840, Rio San Juan, Nicaragua; 

 GUNTHER, Cat. Fishes, iv, 294, 1862; GUNTHER, Fish. Centr. Am., 459, 1869. 



1925. HEROS SALVINI, Giinther. 



Head 2f; depth 2. D. XVII, 10; A. VIII or IX, 7; scales 5-29-10. 

 Head somewhat longer than high; snout of moderate extent, longer than 

 eye, pointed; cleft of mouth very oblique; lower jaw projecting; max- 

 illary not quite extending to vertical from anterior margin of orbit ; eye 

 immediately below upper profile, in middle of length of head ; suboper- 

 culum of moderate width, with 1 series of scales ; preorbital a little nar- 

 rower than orbit, with the antero-inferior margin concave. Length of 

 twelfth dorsal spine f that of head in specimens from Lake Pefcen, and ^ 

 in those from Santa Isabel. Fold of lower lip continuous in middle; 

 scales of cheek in 5 series. Base of soft dorsal scaly. Distance between 

 dorsal and caudal considerably less than depth of free portion of tail ; 

 distance between vent and root of ventrals f length of head. Dark 

 greenish olive, with a black band, edged with yellow, running from 

 snout, through eye, to root of caudal, most distinct on head, but inter- 

 rupted on tail by lighter interspaces; it passes a black lateral spot, and, 

 in young individuals, terminates in another black spot; an irregular 

 black band along back, below base of dorsal fin ; sometimes 3 bands across 

 upper surface of head ; a blue horizontal line below orbit ; a more or less 

 distinct black ocellus on suboperculum sometimes entirely absent; fins 

 blackish, immaculate, or with faint dots only in small number; sides 



* These bands not evident in specimens from Nicaragua examined by us (TJ. S. Nat. 

 Mus., No. 39918). 



