460 DR. GUNTHER ON THE FISHES OF CENTRAL AMERICA. 
being only two-thirds of that of the orbit. The length of the twelfth dorsal spine is 
two-sevenths of that of the head. Yellowish-olive, with six or seven blackish cross 
bands; a black band from the eye to the upper part of the root of the caudal, inter- 
rupted by the interspaces between the cross bands; the origin and end of this band are 
edged with yellow; suboperculum with a black ocellus; an oblique black streak from 
the eye towards the ocellus. 
Lake Peten. Several examples, 5 inches long, were collected by Mr, Salvin. 
175. Heros satyint. (Plate LXXIIL. fig. 3.) 
Heros salvini, Gimth. Fish. iv. p. 294. 
triagramma, Steindachner, Denkschr. Akad. Wiss. Wien, xxiii. p. 70, tab. 3. fig. 2. 
DH. Ow, Sy Te BOT. traney5 10: 
Fold of the lower lip continuous in the middle; scales of the cheek in five series. 
Preorbital a little narrower than the orbit, with the antero-inferior margin concave, 
Base of the soft dorsal scaly. The height of the body is contained twice and a fourth 
in the total length (without caudal), and the length of the head twice and three-fourths. 
Head: somewhat longer than high; snout of moderate extent, longer than the eye, 
pointed, with the cleft of the mouth very oblique, and with the lower jaw projecting ; 
the maxillary does not quite extend to the vertical from the anterior margin of the 
orbit. The eye is situated immediately below the upper profile, in the middle of the 
length of the head. Suboperculum of moderate width, with one series of scales. The 
length of the twelfth dorsal spine is two-fifths of that of the head in specimens from 
Lake Peten, and one-third in those from Santa Isabel. The distance between dorsal and 
caudal is considerably less than the depth of the free portion of the tail. The distance 
between the vent and the root of the ventrals is two-fifths of the length of the head. 
Dark greenish olive, with a black band, edged with yellow, running from the snout, 
through the eye, to the root of the caudal; it is most distinct on the head, but inter- 
rupted on the tail by lighter interspaces ; it passes a black lateral spot, and, in young 
specimens, terminates in another black spot. An irregular black band along the back, 
below the base of the dorsal fin. Sometimes three bands across the upper surface of 
the head. A blue horizontal line below the orbit; a more or less distinct black 
ocellus on the suboperculum is sometimes entirely absent. Fins blackish, immacu- 
late, or with faint dots only in small number. The sides below the black band are 
sanguineous in mature specimens. 
The largest specimen is 43 inches long. 
This species occurs in Lake Peten as well as in the Rio Santa Isabel ; specimens from 
the former locality are distinguished by somewhat longer dorsal spines. H. triagramma 
appears to have been founded on a Lake-Peten example. 
