384 MEMOIRS OF THE CARNEGIE MUSEUM 



237. Pygocentrus niger (Schomburgk). 



Serrasalmo niger Schomburgk, Irishes Brit. Guiana, I, 1841, 225, pi. 18 (in streams 

 between forty and one hundred and fifty miles from coast). — Gunther, 

 Catalogue, V, 1864, 369. 



Pygocentrus niger MtJLLER and Troschel, Horse Ichth., I, 1845, 21, pi. 2, fig. 3. — 

 CuviER and Valenciennes, Hist. Nat. Poiss., XXII, 1848, 286 (Corentyn). — 

 MiJLLER and Troschel, in Schomburgk, Reisen, III, 1848, 636 (upper courses 

 of all streams). — Eigenmann and Eigenmann, Proc. U. S. Nat. Mus., XIV, 

 1891, 59. — Eigenmann, Repts. Princeton Univ. Exp. Patagonia, III, 1910, 442. 

 No specimens of this species were secured. It is said to be very abundant 



and the most voracious of the '"Perais." I have examined the specimen figured 



by Mliller and Troschel. It has forty abdominal serrae and its depth is equal to 



half the length. 



238. Pygocentrus piraya (Cuvier). 



"Piraya," Marcgrave, Hist. Rcr. Nat. Bras., 1648, 164. 



Serrasalmo piraya Cuvier, Mem. Mus. d'Hist. Nat., V, 1819, 368, pi. 28, fig. 4.— 

 Gunther, Catalogue, V, 1864, 368 (Brazil; River Cupai; Demerara). — 

 Cope, Proc. Am. Philos. Soc, XI, 1870, 566 (Para). — Steindachner, "Fluss- 

 fische Siidamerika's," ii, 1881, 13 (Teffe; Rio Puty). — Perugia, Ann. Mus. 

 Genova, (2a), X, 1891, 51 (Villa Maria; Matto Grosso; Rio Paraguay). 



Pygocentrus piraya MUller and Troschel, Horse Ichth., I, 1845, 20. — Cuvier 

 and Valenciennes, Hist. Nat. Poiss., XXII, 1848, 291. — MIiller and Tro- 

 schel, in Schomburgk, Reisen, III, 1848, 636 (generally distributed in Brit. 

 Guiana). — Kner, "Familie der Characinen," ii, 1859, 28. — ? Castelnau, 

 Anim. Am. Sud, Poiss., 1855, 72, pi. 38, fig. 2 (Goyaz; Amazon). — Eigenmann 

 and Eigenmann, Proc. U. S. Nat. Mus., XIV, 1891, 59.— Ulrey, Ann. N. Y. 

 Acad. Sci., VII, 1895, 297 (Trocera on Tocantins). — Fowler, Proc. Acad. Nat. 

 Sci. Phila., 1906, 468 (Para). — Eigenmann, Repts. Princeton Univ. Exp. Pata- 

 gonia, III, 1910, 442. 



Serrasalmo (Pygocentrus) piraya LtJTKEN, Dan. Vidensk. Selsk. Skr., (5), XII, 2, 

 1875, 233 and xvii (Rio das Velhas). 



Serrasalmo piranha Agassiz, Selecta Gen. et Spec. Pise. Bras., 1829, 71, pi. 28. — 

 Schomburgk, Fishes Brit. Guiana, I, 1841, 221, pi. 16 (Rio Branco). 



Serrasalmo nigricans'^'' Agassiz, Selecta Gen. et Spec. Pise. Bras., 1829, 72, pi. 30. — 

 MuLLER and Troschel, in Schomburgk, Reisen, III, 1848, 636 (generally 

 distributed in British Guiana). 



" Liitken ( Vidensk. Med. Nat. For. Kjobenhavn, 1874, 238) considers this a distinct species. The 

 specimen mentioned by Miiller and Troschel, and now in the Berlin Museum, is P. piraya. 



