122 CALIFORNIA ACADEMY OF SCIENCES. 



80, Rhamdia schomburgkii, 



Pimelodus maculatns Schomburgk, Fish. Brit. Guiana, i, 175, 1843. 

 Rhamdia schomburgkii Bleeker, Ich. Arch. Ind. 208, 1858 (Brazil; 



Guiana). 

 Habitat: Guiana; Brazil. 



81, Rhamdia bathyurus, 



Pimelodus bathyurus Cope, Proc. Am. Phil. Soc. xvii, 674, 1878, (Pe- 

 ruvian Amazons). 



Rhamdia bathyurus Eigenm. & Eigenm. Proc. Cal. Acad. 2d Ser. i, 

 124, 1888 (name only). 



Habitat: Maranon. 



82, Rhamdia obesa, 



Rhamdia obesa Eigenrn. & Eigenm. Proc. Cal. Acad. 2d Ser. i, 124, 



1888 (Teffe). 

 Habitat: Teffe. 



Body short and deep; its greatest width less than its 

 greatest depth; head short, its width 1| in its length; 

 width at the angle of mouth 2 in its length, the head 

 flat above, covered with very thin skin, the surface of 

 the bones deeply furrowed, the striations radiating from 

 the eyes and from the pit at the base of the occipital 

 process. Fontanel a narrow fissure between the frontal 

 bones. Occipital process very long, partly concealed by 

 skin, reaching more than half way to the dorsal spine, 

 to near the large, concealed dorsal plate. Pores scattered 

 over the head. 



Eye round, 2J in snout, 6J in head, 2 in the interor- 

 bital; its posterior margin in front of the middle of the 

 head. 



Maxillary barbel (torn on one side) extending to the 

 tips of the middle caudal rays; mentals to the middle of the 

 pectoral; postmentals to half way between tips of pec- 

 torals and base of ventrals. 



Jaws equal, mouth comparatively small, teeth of the 

 mandible as usual; teeth of the upper jaw in a band 

 which is shallowed and interrupted in the middle, its 

 depth about 9 in its width. 



