TRANSFORMATIONS. 161 



organ. Malapterurus is remarkable in that the 

 electric nerves arise from a single, enormous 

 lens-shaped nerve-cell, lying in the neighbour- 

 hood of the head, to wit, near the origin of the 

 second spinal nerve ; it is continued into a large 

 primitive fibre, which passes backwards, giving 

 off branches as it goes, to the end of the tail. 



The use to which these organs are put is pro- 

 bably chiefly for the capture of food. The shock 

 given by Gymnotus is very considerable, quite 

 sufficient to kill other fish, or small mammalia. 

 Humboldt related a story to the effect that the 

 Indians, who wished to procure these eels, drove 

 horses into the water, which caused the eels to 

 discharge so much electricity into the water as to 

 exhaust themselves by their efforts, when they 

 fell an easy prey. The poor horses, it was said, 

 were often killed by the violence of these dis- 

 charges. There is, however, no confirmation of 

 this story by recent travellers. Bates, in his 

 "Naturalist on the Amazons," tells how he amused 

 the Indians, with whom he was travelling, " by 

 showing them how the electric shock from the 

 eels could pass from one person to another. We 

 joined hands in a line, whilst I touched the 

 biggest and freshest of the animals on the head 

 with the point of my hunting-knife. We found 

 that this experiment did not succeed more than 

 three times with the same eel when out of the 

 water, for the fourth time the shock was barely 

 perceptible." This experiment was made upon 

 fishes which had just been taken out of the water. 

 They had been captured, it is interesting to note, 

 from " little ponds " made by the eels in which 

 L 



