350 CHAEACINID^. 



produced into a short lobe. Each scale with a brownish dot at the 

 base ; a broad black band along the middle of the caudal fin. 



Brazil. 

 a-c. Adult : skins. Eio S. Francisco. Purchased of Mr. Gardiner. 



2. Salminus brevidens. 



Hydi'ocyon brevidens, Cuv. Mem. Mus. v. p. 364. pi. 27. fig. 1. 

 Salminus cuvaeii, Cuv. 8f Val. xxii. p. 56. 



D. 11. A. 29. V. 8. L. lat. 80. L. transv. 12/10. 



The length of the head is somewhat less than the height of the 

 body, or than one-fourth of the total (without caudal) ; maxiUary 

 with from 34 to 36 teeth ; operculum thrice as high as long ; the 

 origin of the dorsal fin is nearly in the middle between the extremity 

 of the snout and the root of the caudal. Caudal fin with the 

 midcUe rays produced into a short lobe. Each scale with a brownish- 

 black spot at the base ; a broad black band along the middle of the 

 caudal fin. 



Brazil. 

 (v-h. Adult and half-grown, skins. Cipo River. Presented by Ch. 

 Cumberland, Esq. — Vernacular names : Dourado, Tubarana. 



3. Salminus maxiUosus. 



Hydrocyon brevidens, Valenc. in d'Orh. Voy. Amer. Siid, Poiss. pi. 9. 



fig. 3. 

 Salminus maxillosus, Cuv. ^ Val. xxii. p. 62 ; Castidn. Anivi. Amer. 



Sud, Poiss. p. 61. pi. 30. fig. 2. 

 ? Salminus orbignyanus, Cuv. Sr Val. xxii. p. 65. 



D. 11. A. 27. V. 9. L. lat. 105. 

 The middle caudal rays are somewhat produced, and of black colour. 

 Each scale with a brown dot at the base. (Val.) 

 Amazons ; ? Buenos Ayres. 



35. HYDROCYON. 



Hydrocyon, sp., Cuv. Pi-gne Anim. 



Hydrocyon, Miill. ^- Trosch. Hor. Ichth. i. p. 11. 



The dorsal fin is in the middle of the length of the body, above 

 the ventrals ; anal of moderate length. Body oblong, compressed, 

 covered with scales of moderate size ; belly rounded. . Cleft of the 

 mouth wide, without lips ; the intermaxillaries and mandibles are 

 armed with strong, pointed teeth, widely set and few in number ; 

 they are received in notches of the opposite jaw, and visible ex- 

 ternally, when the mouth is closed. Palate toothless. Cheeks 

 covered with the enlarged suborbital bones. Nostrils close together, 

 situated in the same cavity. Orbit with an anterior and posterior 

 adipose eyelid. GiU-opening wide, the gill-membranes being united 

 quite in front of the throat. Intestinal tract short. 



Rivers of tropical Africa. 



