/OOLOGY* 



165 



branchial orifice or spiracle, single, and situated beneath 

 the throat. 



4. Sphagebranchus, Body Eel-shaped ; pectoral Jins want- 



ing; spiracles two, situated beneath the throat. 



This differs from the last genuSj in possessing two spiracles. 



5. Monopterus. Monoptere. Body Eel-shaped ; nostriU 



situated beneath the eyes ; caudal Jin distinct. 



6. Gymnotus» Gymnote, or Electric Eel. Head furnish- 



ed with lateral opercula ; on the upper lip two tenia- 

 cula ; gill-membrane J composed of five rays ; body 

 compressed ; in most species the dorsal Jin is wanting^ 

 but such possess a narrow fin beneath. 



One of this genus, G. electricus^ possesses the power of 

 benumbing any animal it comes in contact with, by communis 

 eating to it an electric shock ; by the exertion of this power, 

 it stuns such small species as approach it, and then 

 devours them. 



7. Odontagnatus. Mouth furnished with a strong moveable 



lamina or process, on each side of the upper jaw ; gill" 

 membrane five rayed. 



8. Comephorus, Head large, with a compressed snout ; 



mouth large, with small teeth ; body elongated, com- 

 pressed ; the second dorsal Jin furnished with long 

 naked rays. 



M 3 



