318 CHARACINID-5;. 



0. The height of the hody is less than one-half of the total length. 

 * The dorsal fin commences distinctly behind the origin of the 

 ventral, p. 321. 



* * The origin of the dorsal and ventral fins are nearly in the same 

 vertical, p. 328. 



b. Cleft of the mouth rather wide ; maxillary without teeth along its 



edge, long and naiTow, extending to, or nearlj^ to, below the centre 

 of the eye. Dorsal fin above the venti-al : Creatochaties, m., -p. 329. 



c. Cleft of the mouth of moderate width ; the entire edge of the 



maxillary denticulated : Hemibrycon, m., p. 330. 



A. Anal rays forty or more. 

 a. Maxillary with only a few rudimentary teeth near its articulation. 



1. Tetragonoptenis spilurus. 



Cuv. <§• Val. xxii, p. 156. 



D. 11. A. 48. 

 Ventral profile much arched ; snout pointed, A silvery band along 

 the side of the body. {Val.) 

 Surinam. 



2. Tetragonopterus argenteus. 



Cuv. Mem. Mus. iv. p. 455 ; Cuv. ^ Val. xxii. p. 132. 



B. 4. D. 11. A. 40. V. 8. L. lat. 30. 



The height of the body is not less than one-half of the total length 

 (without caudal), the length of the head about one-fourth. Upper 

 profile of the head concave ; diameter of the eye equal to the width 

 of the interorbital space, and one-half of the length of the head. 

 The pectoral extends beyond the root of the ventrals. Maxillary 

 with only a few teeth near its articulation. Two dark cross-bands 

 descend from before the dorsal, one to the gill-opening, the other 

 towards the middle of the pectoral fin. A black spot on the root of 

 the caudal. 



Bahia? 



3. Tetragonopterus rufipes. 



Valenc. in cVOrb. Voy. Amer. Merid. Poiss. pi. 11. fig. 1 ; Cuv. 8f Val. 

 xxii. p. 136. 



D. 11. A. 40. V, 8. L. lat. 30. 



The height of the body is three-fifths of the total length (without 

 caudal), the length of the head somewhat more than a foui'th. Upper 

 profile concave ; eye very large. Maxillary M'ith only a few teeth 

 near its articulation. Body without dark cross-bands ; ventral and 

 anal fins orange-red. ( Val.) 



Buenos Ayres. 



