468 DR. GUNTHER ON THE FISHES OF CENTRAL AMERICA, 



above the root of the ventral, and is not scaly. The spines are of moderate length and 

 strength, the length of the fifteenth being two-sevenths, or in old examples one-third of 

 that of the head. The soft portion does not extend to the caudal, if laid backwards. The 

 free portion of the tail much longer than high. Caudal rounded. Pectoral shorter than 

 the head. The ventral does not extend on to the vent. Eeddish olive, marbled with 

 blackish ; the latter colour forming seven rather irregular transverse bands, some of 

 which extend on the dorsal fin. Belly silvery, marbled with blackish ; opercles and 

 some scales on the body with blue dots. The inner half of the soft vertical fins blackish 

 violet, the outer yellow; spinous dorsal with yellow margin. Lower side of head 

 blackish violet. 



I have now before me numerous examples of this species from the Kivers Chisoy, 

 San Geronimo, and Santa Isabel ; and finding that the anal spines are normally five in 

 number, the number four of tlie typical specimen being merely accidental, I do not 

 hesitate to reunite the genus Theraps with Heros. The largest example in the collection 

 is 8 inches long. 



187. Heros intermedius. (Plate LXXVIII. fig. 1.) 



Giinth. Fish. iv. p. 208. 



D. ^4"r. A. ^. L. lat. 32. L. transv. 5/13. 



The fold of the lower lip is interrupted in the middle ; five or six series of scales on 

 the cheek. The height of the body is contained twice and three-fifths in the total 

 length (without caudal), the length of the head thrice and a fourth. The eye is not 

 very remote from the profile of the nape, which is curved. Head as high as long ; 

 prseorbital rather wider than the orbit. Cleft of the mouth rather narrow, horizontal, 

 with the jaws equal anteriorly. Base of the soft dorsal and anal with scarcely any 

 scales ; dorsal spines of moderate length and strength, the length of the twelfth being 

 one-third or nearly one-third of that of the head '. The soft dorsal and anal extend 

 slightly beyond the root of the caudal. The free portion of the tail is not quite so long 

 as higli. Caudal subtruncated, its lengtli being one-fifth of the total. Pectoral shorter 

 than the head, but rather longer than the ventral, which extends nearly to the vent. 

 Brownish, lower parts red in adult specimens ; a broad angular brown band on the 

 trunk, its horizontal branch extending from the gill-opening to the vertical from the 

 first anal spine, whilst its vertical branch ascends to the hinder dorsal spines. Each 

 scale within this band with a black vertical streak. A rather narrow brown band runs 

 from the angular band to a blackish spot at the root of the caudal. Vertical fins with 

 whitish ocelli, enclosed by reddish streaks. 



This species is closely allied to H. nehuUfer and H. angulif€)\ from which it may be 

 distinguished by its colours, and by the size of its scales. It inliabits Lake Peten, where 

 specimens 5 and 6 inches long were collected by Mr. Salvin. 



' These spines are represented a little too short in the figure. 



