124 CALIFORNIA ACADEMY OF SCIENCES. 



short tentacles. Lateral line sometimes not extending to 

 the caudal fin. 



Chocolate color; head faintly marked with lighter; a zig- 

 zag light bar from gill-openings across the nape; dorsal fin 

 dark brown, a short, transparent bar on the lower half of 

 the last four dorsal rays; base and posterior third of caudal 

 fin dark brown, the intermediate region transparent with 

 dark mottlings; anal dark brown, margined with white, and 

 a white bar on lower half of the last five rays; ventral and 

 pectoral fins dark brown. 



Head 3i; depth 5; Br. 8-9; D. I, 6; A. 10. 



VI. Khamdia Bleeker. 

 Pteronotus Swainson; Pimdonotus Gill; ? NotoglanisG\mih.Qx. 



DOUBTFUL SPECIES. 



I. Pimelodus velifer Humboldt; II. Pimelodus argen- 

 tiniis Humboldt; III. Bliamdia laukidi Schomburgk; IV. 

 Pimelodus grunniens Humboldt. 



§ Nov. ? Occipital process and fontanel none. 



13. Rhamdia breviceps (Kuer.) 



§ Rhamdia. 



14. Rhamdia schomburgkii Bleeker. 



Pimelodus maculutus Schomburgk. 



15. Rhamdia bathyurus Cope. 



16. Rhamdia obesa sp, nov. 



Type, No. 7518. Length .26 m. Teffe. L. A.gassiz. 



Occipital process present; fontanel not continued be- 

 hind the eye; jaws equal; intermaxillary band of teeth of 

 about equal depth throughout; no dark lateral band; pores 

 on the head not aggregated; dorsal I, 6; maxillary barbels 

 extending beyond middle of the adipose fin in the adult. 

 Vent midway between the bases of the caudal and pectoral 

 fins. 



