THE GYMNOTID EELS OF TROPICAL AMERICA. Ill 



The first step toward segregating the Gymnotidce into a separate family was 

 made by Cuvier (1817) in the Regne Animal. He recognized a group, "Les Gym- 

 notes," which he divided into (1) "Les Gymnotes vrais" (the electric eel) ; (2) "Les 

 Carapes" {Gijmnotus carapo), and (3) "Les Apternotes" (the Sternarchinae) . 



The formal family name was assigned to this group by Bonaparte (1846) in 

 the "Catalogue dei Pesci Europei." Cope, in 1871, restricted the family name 

 Gymnotidce to E. electricus and applied the name Sternopygid(e to the rest of the 

 group. Gill (1872) replaced the name Gijmnotidm, as restricted by Cope, with 

 Eledrophoridce, applying the name Gymnotidm to Cope's Sternopygidoe. This 

 nomenclature has been used by most subsequent writers. 



The family was monographed by Kaup in the " Apodes" of the British Museum 

 in 1856. Steindachner described "Die Gymnotidse des K. K. Hof-Naturalien- 

 cabinetes zu Wien" (Sitzb. d. K. Akad. d. Wissensch., 1. Abth., LVIII, 1868). 

 In 1870 Glinther again reviewed the British Museum specimens in Volume VIII 

 of his "Catalogue of the Fishes in the British Museum." In 1905 Eigenmann and 

 Ward published a synoptic revision, "The Gymnotidce" (Proceedings of the 

 Washington Academy of Sciences, Vol. Ill, pp. 159-188, 1905). Von Ihering in 

 his "Os Peixes da agua doce do Brazil" (Revista Museu Paulista, Vol. VII, pp. 

 270-287, 1907), and Schlesinger, in his recent "Die Gymnonoten. Eine phylo- 

 gynetisch-ethologische Studie" (Zoologische Jahrbtichcr, Band 29, Heft 6, 1910), 

 have followed the nomenclature of Eigenmann and Ward almost without change. 



Taxonomy. 

 • Order GLANENCHELI. 



Family GYMNOTID^. 



Gymnotidce Bonaparte, Cat. Metod. dei Pesci Europei, 1846; Kaup, Apodal 



Fish, 124, 1856; GIjnther, Cat., VIII, 1, 1870. 

 Sternopygidoe Cope, Proc. Am. Ass. Adv. Sci., 1871. 

 Eledrophoridce Gill, Arrangement of the Families of Fishes, 1872. 

 GymnotidcE Cope, I. c. 



Body elongate and eel-like; with or without scales; head naked; dorsal fin 

 wanting, or represented by a dorsal thong; ventrals wanting; anal very long; 

 pectorals small and paddle-shaped; caudal small or wanting; the tail terminating 

 in a cylindrical caudal appendage in the species without a caudal ; margin of upper 

 jaw formed by the premaxillary and maxillary; mouth with, or without, teeth; 

 anus never back of the middle of the pectorals, usually well under the head; verte- 

 brae many; shoulder-girdle suspended from the skull; skull with, or without, frontal 

 fontanel, parietal fontanel always present, though much reduced and hidden in 

 two species; symplectic bone present; air-bladder of two parts, the anterior con- 

 nected with the posterior by a small tube; stomach with a blind sac and pyloric 

 caeca. 



