Animal Evolution. 193 



Without entering into minute detail, for full in- 

 formation may be obtained in numerous volumes 

 dealing with the subject, it is only necessary to say 

 that these fishes have powerful electric organs, the 

 whole apparatus consisting of three parts: (1) 

 " Electric centres in the brain or spinal cord, (2) 

 electric nerves passing to the electric organ, and (3) 

 the electric organ itself."* 



The electrical organs are extraordinary structures. 

 That of the torpedo consists of about a million electric 

 plates, each supplied with a distinct nerve fibre, the 

 whole resembling an old-fashioned voltaic pile battery. 

 The torpedo discharges as many as two hundred 

 shocks in the second. The electric currents have all 

 the usual characteristics ; they render the needle 

 magnetic, decompose chemical compounds, and emit 

 the spark. 



A curious fact is that the electric eel knows the 

 nature of its energy, for, like an experienced electrician, 

 it curves its body towards its victim and discharges 

 the shock to the greatest advantage by touching it 

 with both the nose and tail. 



While the normal electric fishes thus wonderfully 

 corroborate our theory of the magnetic and electric 

 character of all life, they fall far short in electric 

 power of their relatives of the deep sea, discovered 

 recently by the United States Fish Commission. 



Bassalia — the name given to the dark deep seas — 



* (< 



Electric Fishes." Dr M'Kendrick. Fortnightly Review, 

 October 1893. 



N 



