COBITID^. 309 



5. SuBFAM. SORUBIN^. 



Head large^ much lengthened_, depressed^ bony ; muzzle 

 broad and obtuse, projecting beyond the lower jaw ; 

 cirri long ; dorsal fins two, the hinder generally adipose ; 

 caudal lobed or forked, rarely lunate. 



Phractocephalus Agassiz.* Head and body thick, 

 the former covered with granulated bony plates, which 

 extend to the first dorsal ; second dorsal fin small, the 

 base adipose, the upper portion with slender soft 

 rays ; eyes very small, nearly vertical ; pectoral spine, 

 as in Aspredo, greatly developed; tail short; the 

 caudal slightly lunate. 



P. bicolor. Spix and Agassiz, pi. 6. 



Pteronotus Sw. Body and muzzle lengthened ; dorsal 

 fins two, the second very long, low, and furnished with 

 numerous soft and slender rays ; vent central ; anal 

 fin short ; caudal forked ; the first dorsal ray slender, 

 spinous, but not longer than the others. 



P. 5-tentaeulatus. Sp. and Ag. pi. 11. 



SoRUBiuM Spi^. ( Platy stoma f Agassiz.) Body and 



head lengthened ; dorsal fins two, the second adipose 



and triangular ; vent nearest the caudal ; anal fin 



short; caudal forked or lobed; muzzle projecting 



beyond the lower jaw. 



S. infra-ocularis. Sp. Ag. pi. 15. maculatuni. lb. pi. 13. 

 truncatum. lb. pi. 13. a. semipunctatum. lb. pi. 14. 



Family 4. COBITID^. 



Generation viviparous ; body lengthened, slimy, covered 

 with minute scales ; mouth very small, placed beneath 

 the snout, with thickened lips ; teeth often wanting ; the 



• This type, by its eyes and pectoral spines, appears to form a passage from 

 the last to the present subfamily ; while Pteronotus seems intermediate 

 between Phractocephalus and Sorubium. 



f Platystoma having been used in ornithology, I retain the original 

 name (although objectionable) of Spix ; but I perfectly agree with Agas- 

 siz in his opinion on the impropriety of barbaric names, whether generic or 

 specific. . 



X 3 



