ON LIVING MALAPTERUKUS. 405 



that the accumulated discharges of both organs strike the central 

 nervous system vertically to its axis. But the truth of the state- 

 ment is not so obvious in any of the three electrical fishes as in 

 the Malapterurus. 



Nevertheless, I did not omit to put it to the test of experiment, 

 and to prove that the discharge actually goes through the body of 

 the fish. For this object, I put insulated copper wire into the 

 body through the mouth and vent of a Malapterurus doomed to 

 death, while an assistant held it with an indiarubber glove. When 

 it was placed in a small parallelepiped glass trough full of water, 

 with the wires in its body, and its skin was excited with a glass 

 rod, it discharged, and the current always showed itself in the 

 circuit of the wires in the right direction and strength. 



The only conceivable reply to the question, why the electrical fish 

 does not kill itself, was evidently that it is very little or not at all 

 sensitive to electric shocks. I had made in the year 1852 experi- 

 ments with Faraday on the Gymnotus of the Polytechnic Institution, 

 in order to discover if the fish is as insensitive to currents of 

 external origin as to its own. We did not succeed in exciting the 

 fish perceptibly ; however it was found that generally even in a 

 man, our apparatus was too weak to produce any appreciable 

 effects * in the large mass of water which contained the animal. 



I was now naturally very eager to obtain from the Malapte- 

 rurus the reply to this question, which had been in my mind for 

 fifteen years. With this object, I let down into the water of the 

 experimental tub, a pair of zinc electrodes as the terminals of the 

 secondary coil of the induction apparatus, and in addition, for a 

 reason to be explained immediately, a pair of platinum electrodes 

 in connexion with half of the length of the nerve multiplier. 

 Two Groves were placed in the primary circuit of the induction 

 apparatus. As I had expected, the multiplier was not affected by 

 the alternating currents of the inductorium, as the current from ifc 

 was too weak to produce a deflection in successively opposite 

 directions. 



When I put into the tub, river-fish of this country, tench, perch 

 (Percafluviatilis), chub (Carassius Gibelio), burbot (Lota flumatilis\ 

 pike (Esox Lucius), Silurus (Silurus Glanis), and exposed them to 

 the current, they tilted over on their side when the coil was 

 pushed up half-way, did not move their gills any more, and drifted 

 about unconsciously. If this condition was allowed to continue, 

 1 Comp. above, p. 380, and Ges. Abh. vol. ii. xxx. 4. 



