290 CLASSIFICATIOX OF FISHES, ETC. 



but having the first dorsal immediately above the 

 ventrals, and the belly sometimes smooth. 

 T. aureus. Spix, pi. 31. chalceus. lb. pi. 33. f. 1. 



Gasteropelicus Bl. Head and mouth directed upwards ; 

 body compressed, very broad at the belly, which is 

 sharp ; the first dorsal short, triangular, placed half- 

 way between the pectoral and the caudal ; anal fin 

 long ; ventral very small, close to the anal ; tail forked; 

 teeth strong : representing Pristogaster. 

 G. sternicla. Blocli, pi. 97. f. 3. 



Chalceus Spix.* Body elongated from the pectoral fin, 

 which is considerably lengthened and pointed ; mouth, 

 teeth, and the situation of the first dorsal as in Serra- 

 salmo ; belly prominent, smooth. 



C. angulatus. Spix and Agass, pi. 34. 



Piahucus Cuv, Body oblong, lanceolate; belly carinated ; 

 mouth small ; teeth minute ; nostrils single ; pectoral 

 fins rather lengthened, pointed ; first dorsal interme- 

 diate between the ventral and anal; the latter very long. 



P. argentinus. B1.382. f. 1. bimaculatus. Bl. 382. f. 2. 

 unimaculatus. lb. 381. f.3. melanurus. lb. 381. f. 2. 



XiPHosTOMus Sj)ijc. Body oblong, lanceolate ; jaws 

 more or less lengthened ; the upper considerably an- 

 gulated towards the gape, and both armed with sharp 

 unequal teeth. 



Hydrocyon Cuv. Resembling Piahucus in its fins ; but 

 the jaws are produced, the upper strongly angulated, 

 and both furnished with acute unequal teeth ; the 

 mouth is cleft in an horizontal direction, as in the 

 true salmons ; anal fin very long. 

 H. falcatus. Bl. 385. 



Xiphostoma Spix. Body nearly linear ; scales hard, 

 carinated; jaws considerably prolonged and pointed, 

 the upper one longest ; anal fin short, triangular ; 



* I introduce this supposed type from having previously mentioned it, 

 but it appears to ine to be no other than an aberrant species oi Piabucus, 

 connecting this latter with Gasteropelicus. 



