340 Bulletin ^7, United States National Museum. 



loug. Scales small or wanting. Kibs well developed. Air bladder pre- 

 sent, double. Stomach with a blind sac and iiyloric croca. Ovaries with 

 oviducts. Fresh-water fishes from South America, about thirty species 

 being known. The group is divisible into two families quite diverse from 

 each other, the one containing the singular Electric Eel, (Elcctrojihoras 

 elcciricus), which Cope regards as intermediate between the eel-like Silu- 

 roids, {Clarildcr), and the Eels. In this group the maxillaries are rudi- 

 mental and the form decidedly eel-like. The remaining species, consti- 

 tuting the suborder Gymnonoti, resemble the Characins rather than the 

 Eels, and have no appreciable relationships to the latter. It seems to us 

 unlikely that any of the Eels are descended from fishes like the Gymnon- 

 oti, with the anterior vertebrae modified. The eel-like form of Electro- 

 chorus is probably the result of independent skeletal degradation. ( Gym- 

 notidw, Giinther, Cat., viii, 1-11, 1870.) (yv/nvog, naked; I'tJrug, back.) 



Family XL. GYMNOTIDiE. 



Body elongate, compressed, covered with rather small scales, the tail 

 much produced and usually ending in a point. Mouth small, the teeth 

 moderate, sometimes wanting, the margin of the upper jaw formed partly 

 by the maxillaries. Dorsal fin absent or reduced to an adipose strip; 

 caudal fin rudimentary or wanting; no ventrals. Vent close behind the 

 head, the anal fin very long. Genera 6; species 30; abounding in the 

 rivers of South America, with the Characinidw, to which group they are 

 probably most closely related. (Giinther, Cat., viii, 1-9, 1870.) 



a. Tail ending in a point without fins; no trace of dorsal fin. 



b. Each jaw with a series of conical teeth. Giton, 146. 



6b. Each jaw with a patch or band of very small teeth; eyelid covering the eye, without 



free rim. Eioenmannia, 147. 



146. GITON, Kaup. 



Carapus, Cuvieb, Kegne Animal, Ed. i, 237, 1817, (in part ; macroimis, fascialns, etc.). 



Carapus, Mulleb & Teoschel, Horie Ichthyol., iii, 13, 184.5, (restricted topfasciatus ; not Carapus, 



Rafinesque). 

 Giton, Kaup in DuMfiElL, Analyt. Ichth., 201, 1856, (fiiscialiis ; no description.) 



Snout of moderate length, depressed. A series of conical teeth in each 



jaw. Lower jaw projecting. Anterior nostrils wide, in the ui)per lip. 



No trace of caudal or dorsal fin. Vent below the gill opening, (ytiruv, 



neighbor.) 



670. GITON FASCIATUS (Pallas). 



(Caeapo.) 

 Eye very small ; scales moderate. Anal beginning below point of iiec- 

 toral; teeth ^^^^. Color dusky, the young with irregular dark cross- 

 bars, which break up into spots with age. Guatemala to Rio de la Plata; 

 generally abundant, especially in South America; recorded from Rio 

 Matagua and Grenada, (faaciatus, banded.) 



Carapo, Maecgbave, Hist. Pise. Bras., 170, 1048, Brazil. 



Gynmotus fiiKciatus, Pallas, Spicilegia Zoiil., vii, 35, 1709, anal rays about 180, fresh waters of 



America. 

 GymnotM albiu, Pallas, I. c, 36, 1769, Surinam. 

 Gymnotus brachiurus, Blocu, pi. 157, fig. 1, 1787. 



