112 CALIFORNIA ACADEMY OF SCIENCES. 



77, Pseudopimelodus zungaro, 



Pimelodus zungaro Humboldt, Obs. Zool. ii, 170, pi. xlvi, fig. 1, 1833 

 (Marafion); Cuv. & Val. Hist. Nat. Poiss. xv, 160, 1840 (copied); 

 Schomburgk, Fish. Guiana, ii, 205, 1843 (Tomepeuda, Am- 

 azon). 



Pseudopimelodus zungaro Eigenm. & Eigenm. Proc. Cal. Acad. Sci. 

 2d Ser. vol. i, 1888, 122 (Goyaz). 



Pimelodus bufonius Cuv. & Val. Hist. Nat. Poiss. xv, 155, 1840 

 (Cayenne); Kner, SB. Ak. Wien, xxvi, 1857, 421 (Cujaba); 

 Giinther, Cat. Fish. Brit. Mus. v, 133, 1864 (Eio Cipo tributary 

 to the Rio das Velhas); Cope, Proc. Am. Philos. Soc. 17, 1878, 

 675 (Peruvian Amazons); Steindachner, Fisch-Fauna des Cauca 

 and Fliisse bei Guayaquil, 7, pi. ii, figs. 1-lb. (Cauca). 



Pimelodus charus Cuv. & Val. Hist. Nat. Poiss. xv, 159, 1840 (Eio 

 Sabara). 



Pseudopimelodus charus Liitken, Dan. Selsk. Skr. 1875, 180 (Rio 

 das Velhas). 



Pimelodus mangurus Valenciennes, Voy. d'Orbigny, pi. i, figs. 4-6, 

 1847 (Rio Plata); Cuv. & Val. Hist. Nat. Poiss. xv, 156, 1840 

 (Brazil; Paraguay); Giinther, Cat. Fish. Brit. Mus. v, 134, 1864 

 (copied). 



Zungaro humboldtii Bleeker, Nederl. Tijdschr. Dierkunde, i, 1863, 

 101 (name only). 



Habitat: Rio Plata, Rio Magdalena and the region between. 



We have examined four specimens of this species col- 

 lected by Senhor Honorio at Goyaz. They measure .12, 

 ,14, .20, and .21 m. respectively, to the base of the caudal 

 fin. One of these specimens has 7 dorsal rays and 

 represents mangurus. Thus, like several species of 

 Rhamdia the southern representatives of this species are 

 seen to be liable to have more rays. The two forms, 

 mangurus and bufonius, r cannot be separated. 



There can be little doubt but that Pimelodus zungaro 

 is identical with P. mangurus. The head and adi- 

 pose fin of zungaro are shaped as in a Pseudopimelodus; 

 the eye is small and placed well forward. The dorsal 

 and pectoral spines of mangurus are short, with a long, 

 flexible prolongation and the skin covering them very 

 thick, accounting for the statement that zungaro has 

 no spiny rays. The ventral rays of mangurus are 



