5M ORDER MALACOPTERYGII APODES. 



We may, perhaps, distinguish some species with 

 an elongated muzzle, open only at the end 1 . 



Apteronotus, Lacep. Sternarchus 2 , Schn., 



Have the anal fin terminated before it arrives at the 

 end of the tail, which has a particular fin ; on the 

 back is a fleshy filament, soft, couched in a furrow, 

 hollowed as far as the end of the tail, and retained in 

 this furrow by tendinous filaments, which leave it 

 some liberty : a very singular organization, the use of 

 which we have as yet been unable to divine 3 . Their 

 head is oblong, compressed, naked, and its skin does 

 not suffer either the opercula or the rays to be seen 

 externally. The rest of their body is scaly. Their 

 teeth are close and even, and scarcely perceptible on 

 the middle of each jaw. They come from America, 

 like the gymnoti proper, and the carapi 4 . 



Gymnarchus, Cuv., 



Have the body scaly and elongated, and the gills but 

 slightly open in front of the pectorals, like the gym- 



1 Gymnotus rostratus, Schn. pi. cvi. 



2 Sternarchus, (anus at the sternum.) 



3 I think that I have perceived that the separation is accidental, 

 and that it is properly one of the muscles of the tail, which is easily 

 detached, because the skin is weaker in this part. 



4 Gymnotus albifrons, Pall. Spic. Zool. VIII. pi. vi. f. 1. Lacep. II. 

 vi. 146. 3. 



N.B. The Gymnotus ocus, or fierasfcr, belongs to the Donzelles, 

 and the Gymnotus noloplerus, Pall, and Gm. Notoptere capital, 

 Lacep., to the herrings. 



