"^"U^!' ] PROCEEDINGS OF THE NATIONAL MUSEUM. 25 



6, 7. POTAMOTRYGON Ganuau. 



6. P. brachyuius Giinthor. La Plata. G., '80, 8. 



7. P. hystiix Miiller »fe Ileule. Roawa ; Rio Plata ; Apur6; Orinoco; Rio Branco. 



G., '80, 7. 



8. P. d'orbignyiCastlenau. Tocantins; Orinoco near Ciudad, Bolivar. G.,viii, 484. 



9. P. reticulatus Giintber. La Plata ; Siiriuani ; Santareni. G., viii, 482, as T. //^s- 



10. P. magdalenae Steind. Rio Magdalena. Steind., '78, 56. 



11. P. motoro Miiller &. Henle. Rio Cuyaba. G., viii, 484. 



Tryijon (jarrapa Schombiirgk. 



12. P. dumerilii Castlenau. Araguay; Tocantins, Rio Crixas. G. viii, 484. 



T. mUlleri and henlei Castlenau. 



8. ELLIPESURUS* Schomburgk. 



13. E. spiuicauda Schomburgk. Rio Branco, near Fort joaquiiu. G., viii, 472. 



DIPNOI. 



IV. LEPIDOSIRENIDiE. 



9. LEPIDOSIREN Fitzinger. 



Amphibichthys Hogg. 



14. L. paradoxa F. Madeira near Barba ; Amazon near Villa Nova. G., viii, 322. 



L. (iissimilis Castelnau. 



SYMBRANCHIA. 

 V. SYMBRANCniD^. 



10. SYMBRANCHUS Bloch. 



Unihranchapertura 'Lac6Yihde ; Ophisternon McClelland; Tetrabraiichus Bleeker. 



15. S. marmoratus Blocb. Porto Alegre ; Pernaiubuco ; Amazons and northward. 



G., VIII. 



S. immaculatus Blocb ; S. transiwi'salis Bl. & Schn. ; Unibranchapotura grisea 



Lacdp. ; Unibranchapertura lincata Lac6p. ; S. fuUginosus Ranzaiii ; Murcvna 



lumbricus Gronow ; S. viitatus Castelnau. 



NEMATOGNATHI.f 



VI. ASPREDINIDaE. 

 BUNOCEPlIALINiE. 



11. BUNOCEPHALICHTHYS Bleeker. 



16. B. hypsiurus (Kner). Rio Branco. 



* ElUpesurus is retained only provisionally. "EUipesuru)i spinieauda of Schomburgk 

 is probably a mutilated specimen of one of the varieties" of P. Dumerilii. See Gar- 

 man, '78. 



t The species of this order are described in A Revision of the South American Ne- 

 matoguathi E. and E., 1890, and no other references will be given to descriptions. 



