4(i2 DR. GUXTIIER OX THE FISHES OF CENTRAL AjMERICA. 



si)iucs slender, the length of the twelfth of the dorsal fin bemg 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 towards the root of the pectoral ; 

 a black spot behind the angle of the mouth. 



This species is allied to H. friednchsthalii, H. salvini. Sec. Two specimens, 6 inches 

 long, were collected by Capt. Dow in the Lake of Nicaragua. 



Desoiption. — Head much longer than high. Snout rather elongate, much longer than 

 the eye, pointed, with the cleft of the mouth oblique, and the lower jaw very prominent. 

 The maxillary reaches the vertical from the anterior margin of the orbit. The width of 

 the orbit is contained four times and a half in the length of the head, and equal to that 

 of the interorbital space. The eye is situated immediately below the upper profile, but 

 is considerably nearer to the end of the snout than to that of the operculum. Opercles 

 scaly, the scales on the operculum larger than those on the cheek ; suboperculum with 

 two sex'ies of scales. The soft portions of the dorsal and anal fins are scaly at the base, 

 and do not reach much beyond the origin of the caudal. Caudal rounded. The 

 pectoral is about two-thirds as long as the head, and scarcely reaches the vertical from 

 the origin of the anal. Ventral pointed, slightly produced, reaching only to the vent. 

 The distance between the vent and the root of the ventral is two-fifths of the length of 

 the head. 



178. Heros motaguexsis. (Plate LXXVII. fig. 2.) 

 D. j^. A. g^,. L. lat. 32. L. transv. 5/13. 



The fold of the lower lip is continuous in the middle. Snout pointed, with the lower 

 jaw prominent. Pncorbital with the antero-inferior margin but slightly concave, its 

 greatest width being equal to that of the orbit. Dentition as in //. domi. Scales on 

 the cheek small, in eight series. The first dorsal spine is inserted behind the vertical 

 from the upper end of the gill-opening. Dorsal and anal spines short, the length of 

 the twelfth of the dorsal fin being two-ninths of that of the head. Brownish, a black 

 interrupted band runs from the eye to a spot on the root of the caudal, this spot being 

 situated above the lateral line. An oblique short black streak runs from the lower 

 posterior angle of the orbit towards a spot situated on the suture between operculum 

 and suboperculum, close to the interoperculum, the band being not continuous with the 

 spot. Back with traces of iiTegular cross bands, more distinct in young than in old 

 individuals. Vertical fins with numerous brown dots. 



Five examples, from 4 to 10 inches long, were obtained by Mr. Godman from the Rio 

 Motagua. This species is closely allied to H. friedrichsthalii. 



Description of an example 10 inches Jong. — The height of the body is nearly equal to 

 the length of the head, and is contained thrice in the total length (without caudal) ; the 

 lengtli of tlie head is contaii\ed twice and five-sixths in the same. Head longer than 



