136 CALIFORNIA ACADEMY OF SCIENCES. 



XV. SciADES Miiller & Troschel. 

 Leiarius and Sciadeichthys Bleeker. 



^ Sciades. 



68. Sciades pictus Miiller & Troschel. 



Arius longlbarhis Casteluau. 

 Localities: Eio Negro; Villa Bella. 



§ Sciadeoides no v. 



Surface of the head and occipital process entirely covered with thick 

 skin. Head little longer than broad. 



69. Sciades marmoratus Gill. 



Localitj': Tabatinga. 



XVI. Brachyplatystoma Bleeker. 

 Piratinga and Malacobagrus Bleeker. 



70. Brachyplatystoma filamentosum (Lichtenstein.) 



71. Brachyplatystoma vaillanti (Cuv. & Val. ) 



Platystoma affine Gn'v.& Val). Plat t/sio ma mucosa \&\lleint.^=P laty- 



sioma verrucosum Bonleuger. 

 Localities: Tabatinga; Parii; Porto do Moz; Avary; Eio Puty; Juiz 



de Fora on the Parahyba. 



72. Brachyplatystoma reticulata (Kner.) 



73. Brachyplatystoma rousseauxii (Castelnau.) 



Bagrus goUath Heckel. 

 Locality: Para. 



XVII. DuoPALATiNus gen. nov. 



Head narrow, little depressed, the width of the snout 1| 

 in the greatest width of the head. Upper jaw little longer 

 than the lower. Teeth all alike, the vomerine patches far 

 removed from the palatine patches. Adipose fin twice as 

 long as anal. 



This genus is most nearly related to Brachyplatystoma in 

 which the teeth of the inner series of the intermaxillaries 

 are long, slender and depressible; of the outer series short, 

 recurved and fixed. 



