Odd Fish 163 



can be suddenly erected and locked by 

 special trigger - like muscular attach- 

 ments. 



Of ways of catching prey there is no 

 end. A number of widely diverse types 

 of fish employ that very up-to-date 

 weapon, electricity, which may be gener- 

 ated by special nerves, glands or muscles. 

 In the electric eel of the shallows of the 

 rivers Orinoco and Amazon the electric 

 organs, which extend in two series on 

 either side of the fish's tail, are capable 

 of producing a shock the equivalent of 

 nearly 400 volts. Like all other electric 

 fish the " eel " cannot give shocks in- 

 definitely, for there comes a time when 

 it must rest for a period to recuperate 

 the electrical energy expended, and there 

 is a story told by Humboldt of South 

 American natives deliberately driving 

 horses into a stream infested by electric 

 eels in order to incite the fish to exhaust 

 themselves. When " played-out " and 



