DEC. 28, 1916. FISHES or PANAMA MEEK AND HILDEBRAND. 307 



cc. Orbital margin not free; eye covered by a transparent mem- 

 brane. 



d. Teeth wanting; origin of anal about the length of pectoral fin 

 behind gill-opening. Hypopomus, p. 309. 



dd. Teeth present in both jaws; origin of anal under or slightly 

 behind base of pectorals. Eigenmannia, p. 311. 



bb. Caudal fin and dorsal filament present; mouth large, its angle 

 little, if any, in front of eyes. Sternarchus, p. 312. 



33. Genus Gymnotus Linnaeus. 



Gymnotus Linnaeus, Syst. Nat., Ed. X, 1758, 246 (type Gymnotus carapo 



Linnaeus). 



Size moderate, not exceeding 600 mm. in length. No frontal fon- 

 tanel; no caudal fin; a dorsal filament; no electrical organs; cylindrical 

 anteriorly, somewhat compressed posteriorly; head large and depressed, 

 the top quite flat; gape not reaching the eyes; lower jaw protruding; 

 teeth small, conical, in one row (which is sometimes irregular) in each 

 jaw; eyes small and covered by membrane, without free orbital margin; 

 scales cycloid and very small; lateral line complete and paralleling the 

 main axis of the body; pectorals small; anal long, its origin back of 

 vertical from the tip of the pectoral. (Ellis.) 



Of this genus only a single widely distributed species is known. 



49. Gymnotus carapo Linnaeus. 



Gymnotus carapo Linnaeus, Syst. Nat., Ed. X, 1758, 246, and Ed. XII, 



1766, 427; Meek, Field Mus. Nat. Hist. Pub., Zool. Ser., VII, 1907, 



135 (LosAmates and Lake Amatitlan, Guatemala) ; Ellis, Memoir. 



Carnegie Mus., VI, 1913, 117 (Guatemala, south to the Rio de la 



Plata and the West Indies). 

 Gymnotus fasciatus Pallas, Spicil. Zool., VII, 1769, 35; Schomburgk, 



Fishes of Guiana, 1843, 184, PI. 19 (Rio Branco). 

 Gymnotus albus Pallas, Spicil. Zool., VII, 1769, 36 (Surinam). 

 Gymnotus brachyurus Bloch, Syst. Ichthyol. 1787, Taf. 157, fig. i. 

 Gymnotus putaol Lace"pede, Hist. Nat. Poiss., II, 1800, 176. 

 Carapus fasciatus Cuvier, Regne Animal, Ed. I, II, 1817, 237. 

 Carapus brachiurus Cuvier, Rgne Animal, Ed. I, II, 1817, 237. 

 Carapus inaquildbiatus Valenciennes, in d'Orbigny, Voy. Ame"r. Me"rid., 



V, Pt. 2, 1847, u, PI. 14 (La Plata). 

 Giton fasciatus Kaup, in Dumeril, Analyt. Ichthyol., 1856, 201; Jordan 



& Evermann, Bull. U. S. Nat. Mus., XLVII, 1896, 340 (Guatemala 



to Rio de la Plata). 



