108 ORDER MALACOPTERYGII ABDOMINALES. 



Others have the muzzle pointed, and no teeth, or 

 teeth scarcely perceptible. Their maxillary barbels 

 sometimes have lateral setae \. 



Heterobranchus, Geoff., 



Have the head furnished with a rough, flat buckler, 

 and broader than in any other silurus, because the 

 frontals and parietals give out lateral plates, which 

 cover the orbit and the temple ; the operculum is 

 still smaller in proportion than in the preceding 

 genera, and what distinguishes these from all other 

 fishes, is the peculiarity observed by M. Geoffroy, 

 that independently of the ordinary branchiae, they 

 have apparatus ramified like trees, adhering to the 

 superior branch of the third and fourth branchial arch, 

 and which appear to be a sort of supernumerary gills. 

 For the rest, their viscera resemble those of the other 

 siluri. Their branchial membrane has from eight or 

 nine to thirteen or fourteen rays; their pectoral spine is 

 strong and dentated, but nothing of this is to be found 

 on the dorsal ; their body is naked and elongated, as 

 are also the dorsal and anal ; there is no spine to the 



also the Cataphractus Americanus, Catesb. Suppl. ix., usually cited 

 under Sil. cataphractus; aS'/7. carinatus, Lacep., which appears to 

 me the same as Gronov. iii. 4, 5, also usually cited under S. cata- 

 phractus, and as the Klip-bagre, Marcgr. 174; thus the species 

 of Sil. cataphractus, should be reduced to nothing. Doras granu- 

 losus Valenc. ap. Humb. Obs. Zool. ii. 183. 



1 Doras niger, Valenc. loc. cit. or Corydoi us ec'entulus, Spix v. 

 Dor. oxyrhyncus, Val. lb. 



