130 CALIFORNIA ACADEMY OF SCIENCES. 



body and rather small eyes; Rio Parahyba: reddish 

 brown with dark markings, caudal black; Rio Grande 

 do Sul, Emperor's collection, one specimen, has D. I, 7. 



89. Rhamdia multiradiatus. 



Pimelodus multiradiatus Kuer, SB. Ak. Wien, xxvi, 414, 1857, 



(Borba ou the Eio Madeira; Forte do Kio Branco on the Eio 



Facutu). 

 Notoglanis multiradiatus Giinther, Cat. Fish. Brit. Mus. v, 136, 1864 



(copied). 

 Eham,dia multiradiatus Eigeum. & Eigeum. Proc. Cal. Acad. 2d Ser. 



i, 126, 1888 (uaine). 

 Pimelodus arekaima Schombiirgk, Fish. Brit. Guiaua, part i, 178 



(not plate v), 1841 (Upper Essequibo). 

 Habitat: Amazon and its tributaries, and northward. 



90. Rhamdia sapo. 



Pimvlodus sapo Valenciennes, in Voy. d'Orbigny, ix, Atlas ii, pl.ii, 

 figs. 6-8, 1847; Cuv. & Val. Hist. Nat.Poiss. xv, 179, 1840 (Bue- 

 nos Ayres); Kner, SB. Ak. Wien, xxvi, 417, 1857 (loc.?); Giin- 

 ther, Cat. Fish. Brit. Mus. v, 132, 1864 (Eio Plata); Steindach- 

 ner, SB. Ak. Wien, Ix, 1869, Ichthyol. Notiz. ix, 5 (Montevi- 

 deo); Hensel, Wiegm. Arch. 1870, i, 69 (Guahyba). 



Pimelodus (Rhamdia) sa^jo Steindachner, SB. Ak. Wien, Ixxiv, 1876, 

 Stisswasserfische stidostl. Bras, iii, 60 (La Plata; Eio Grande 

 do Sul). 



Rhamdia sapo Eigenm. & Eigenni. Proc. Cal. Acad. 2d Ser. i, 126, 

 1888 (Eio Grande do Sul). 



Habitat: Eio Plata; southern Brazil. 



Five specimens from .18-.405 m. in length, from the 

 Rio Grande do Sul, the Emperor's collection. 



Body rather robust, its greatest width less than its 

 greatest depth. 



Head elongate, flat above, its greatest width 1\ in its 

 length; width at the angle of the mouth 2 in head; the 

 head entirely covered with skin; fontanel not continued 

 behind the eye; occipital process small, imbedded. Large 

 patches of radiating pores between and behind the eyes, 

 on the upper and lower angles of the opercle; the patches 

 with fewer pores in some individuals; in the adult the 

 pores on top of the head become detached and circular; 

 minute, inconspicuous pores scattered everywhere about 

 the head. 



