48 



This genus was first naturally characterized by Dr. Bleaker and 

 the present author, at nearly the same time. Dr. Bleeker's name 

 appears to have been published a short time before ours. His name is 

 therefore now adopted. The names of M>/stus and Pteronotus cannot 

 be retained, as both had been previously used for valid genera ; 

 Pteronotus was also given from a misconception of the characters 

 of its type, Swainson having established the genus for the Het^ro- 

 hranchus sextentaculatus of Spix, on account of its second dorsal 

 being supposed to be furnished with true rays. 



Head obliquely compressed, gradually narrowed to the snout. 

 Supraoccipital bone posteriorly acuminate, but free. Dorsal fin with 

 a more or less slender spine. 



Type Rhamdia Sebse Bleeker. 



Syn. Pimelodus Sebae ('uv. et Vol. 



§ 2. Body comparatively short and robust. 



Head large, depressed, covered with the generally thick skin, and 

 with the muzzle horizontally convex or rounded. 



Mouth large. Supraoccipital bone posteriorly free. 



Eyes small. Adipose fin thick and short. Caudal fin not forked. 



Genus Pseudopimelodus Bleeker. 



SY]SONYMY. 



Pseudopimelodus Bleeker, Ichthyologiae Archipelagi Indici Prodro- 



mus, vol. I. Siluri, pp. 169, 204. August, (?) 1858. 

 Batrachoglanis Gill, Synopsis of fresh-water fishes of Trinidad, p. 29 ; 

 lb. in Annals of Lyceum Nat. Hist, of New York, vol. vi. Sept. 

 1858. 



Branchiostegal membrane with nine or ten rays on each side. 

 Ventral fins with one simple and five branched rays. Dorsal and 

 pectoral spine quite strong or moderate. 



This genus may be considered as representing, in South America, 

 the Amiuri of the Northern Continent. But it is perhaps entitled to 

 this distinction only on account of its form. The number of known 

 species is only six, and most of them appear to be quite rare. 



As in the case of the nearly synchronous names of Bhamdia and 

 Pimelenoius, we have adopted Bleeker's name of Pseudopimelodus in 

 preference to our Batrachoglanis. The first species, and consequently 

 the type, of Bleeker's genus is Pimelodus hufonius of Valenciennes ; 

 that of Batrachoglanis was expressly stated to be the Pimelodus rani- 

 nus of the same naturalist. 



Type Pseudopimelodus bufonius Bleeker. 



Syn. Pimelodus bufonius Val. 



