368 CHARACINID.2E. 



** Wo teeth on tne palate ; teeth in the jaws simply cutting : 

 Pygocentrus, M. & 1. 



3. Serrasalmo piraya. 



Piraya, Marcgr. Hist. Nat. Bras. p. 164. 



Serrasalmo piraya, Cuv. Mem. Mus. v. p. 368. pi. 28. fig. 4 (had). 



piranha, Spix, Pise. Bras. p. 71. tab. 28. 



? Serrasalmo nigricans, Spix, I. c. p. 72. tab. 30 (young ?). 

 Pygocentrus piraya, Mull. Sf Trosch. Hor. Ichth. l. p. 20 ; Cuv. 8f Vol. 



xxii. p. 291 ; Kner, Denkschr. Acad. Wiss. Wien, 1860, xviii. p. 36 ; 



(? Casteln. Anim. Amer. Sud, Poiss. p. 72. pi. 38. fig. 2.) 

 ? Pygocentrus nigricans, Mull. Sr Trosch. I. c. p. 21. 



D. 17-18. A. 30-33. V. 7- L. lat. 95-100. 



The height of the body is more than one-half of the^ total length 

 (without caudal) ; snout very obtuse, short ; the width of the inter- 

 orbital space is only a little less than one-half of the length of the 

 head. The second infraorbital bone touches, or nearly touches, the 

 praeopercular limb. The origin of the dorsal fin is considerably 

 nearer to the root of the caudal fin than to the end of the snout. 

 Abdominal serrature composed of from twenty -four to twenty-seven 

 spinous plates. Adipose fin in old specimens rayed. Gill- rakers of 

 the outer branchial arch lanceolate. 



Brazil, Guiana. 



a. Adult : stuffed. Brazil. Purchased of Mr. Parreys. 



b. Fine specimen. River Cupai. Purchased of Mr. Stevens. 



c. Adult : skin. Demerara. From Mr. Scrivener's Collection. 



d. e-f. Young. From the Haslar Collection. 



4. Serrasalmo scapularis. 

 D. 15-16. A. 32-34. V. 7. L. lat. 95. 



The height of the body is contained once and three-fourths in the 

 total length (without caudal), the length of the head thrice and one- 

 eighth; nape ot the neck much elevated, the upper profile of the 

 head, above the eye, a little concave. Snout very obtuse, and short, 

 with the mandible prominent ; the diameter of the eye is one-fourth, 

 the width of the interorbital space two-fifths of the length of the 

 head. There is a stripe of naked skin between the second infraorbital 

 bone and the limb of the praeoperculum. The. origin of the dorsal fin 

 is considerably nearer to the root of the caudal fin than to the end 

 of the snout. Abdominal serrature composed of twenty-seven or 

 twenty- eight spinous plates, the spines being not very prominent. 

 Gill-rakers of the outer branchial arch short, with broad base and 

 with a slender iip. Silvery, iridescent, sometimes with small blackish 

 spots ; a large blackish blotch behind the gill-opening ; vertical fins 

 blackish . 



Essequibo River. 



a-c. Fine specimens, from 6 to 8 inches long. From Mr. Ehrhardt's 

 Collection. 

 Half-grown. British Guiana. Presented by Sir R. Schomourgk. 



