154 DR. A. GUNTHER ON GUATEMALAN FISHES. [Mar. 22, 
(without caudal); the length of the head twice and one-fifth. Head 
much higher than long, in consequence of an adipose swelling above 
the eye, which renders the shape of the head Coryphena-like. 
Scales on the cheek in six series, rather irregularly arranged. The 
first dorsal spine is inserted above the upper end of the gill-opening. 
Dorsal and anal spines slender, the sixteenth of the dorsal fin being 
one-half of the length of the head. Pectoral not quite as long as 
the head. Brownish olive above, yellowish below; back with five 
black cross bands, not extending downwards to beyond the middle 
of the side; many scales with a brown vertical marginal streak. 
The soft vertical fins with brown spots. 
One specimen, 64 inches long, was collected by Capt. Dow in the 
Lake of Nicaragna. 
HEROs DovIil. 
D. Sy. A. L. lat. 35. L. transv. 2. 
The fold of the lower lip is continuous in the middle. The height 
of the body is contained thrice in the total length (without caudal) ; 
the length of the head twice and three-fifths. Snout pointed, with 
the lower jaw very prominent. Both jaws with a pair of fangs, 
those of the upper pair being close together in the middle of the 
jaw, whilst the lower are separate. Scales on the cheek small, rather 
irregularly arranged, in about eight series. The first dorsal spine is 
inserted behind the vertical from the upper end of the gill-opening. 
Dorsal and anal spines slender, the length of the twelfth of the dor- 
sal fin being one-fourth of that of the head. Pectoral three-fifths 
as long as the head. Brown, irregularly marbled with darker ; fins 
black ; an indistinct black band along the operculum and the side 
of the trunk; an oblique blackish band descends from the eye to- 
wards the root of the pectoral; a black spot behind the angle of the 
mouth. 
This species is allied to H. friedrichsthalii, H. salvini, &e. Two 
specimens, 6 inches long, were collected by Capt. Dow in the Lake 
of Nicaragua. 
HEMIRHOMBUS OVALIS. 
D. 86. A. 69. L. lat. 58. 
The height of the body is scarcely less than one-half of the total 
length (without caudal). Interorbital space concave, its width being 
one-third of the vertical diameter of the eye. Body nearly uniform 
reddish olive. 
One specimen, 7 inches long, was collected by Messrs. Dow and 
Salvin on the Pacific coast of Panama. 
