172 VERTEBRATA. PISCES. 



some distance, and the smaller fishes are even killed 

 at the distance of fifteen feet. The shock increases 

 in violence, according to the health, the activity, and 

 especially the rage of the animal. After exerting its 

 powers awhile, it becomes exhausted, and must re- 

 cruit them by repose and nourishment. Some per- 

 sons are affirmed to be exempt from its influence. 

 The organ producing this astonishing effect, con- 

 sists of two large bundles of tendinous fibres on 

 each side, occupying the hinder part of the body ; 

 they are crossed at right angfes, by other plates of 

 the same kind, forming a wide and deep network of 

 minute cells, filled with a jelly-like substance : 

 an enormous voltaic pile. Humboldt graphically de- 

 scribes a display of the terrific powers possessed by 

 these animals. " We were greatly surprised when 

 they informed us they were going to catch about thirty 

 half-wild horses in the neighbouring savannahs to 

 employ them in fishing for these Electric Eels. While 

 our host was explaining to us this strange system 

 of fishing, a troop of horses and mules arrived. The 

 Indians had made a sort of enclosure around them, 

 and, pressing them closely on all sides, forced them to 

 enter the water. I shall but imperfectly depict the 

 interesting spectacle presented to our view by the 

 combat of the Eels against the horses. The Indians 

 provided with very long reeds and harpoons, placed 

 themselves around the basin. Some of them mount- 

 ed on trees, whose branches overhung the surface of 

 the water. They all, by their cries, and the length 

 of their reeds, prevented the horses from attaining 



