ELECTRICAL FISHES 413 



making preparations from the organ of Torpedo, Schonlein 

 usually observed a discharge on cutting through the skin, as 

 well as on removing the cranium, especially if the canals and 

 utriculus were broken into. Division of the medulla oblongata 

 was also accompanied by a discharge. 



The relatively considerable duration of all spontaneous or 

 reflex discharges is apparent not merely in subjective sensations, 

 but also objectively with the above modes of investigation. 

 With strong excitation, the hammer of the frog -alarum is 

 .(intinuously pressed against the bell in both Gymnotus and 

 Malaptcrunis. When Malaptcrii.rus is excited, it seldom discharges 

 once only. The bell usually rings 2-3 times, either in quick 



\ 





\ 



i i i \ ^inm iwiid j 



\\\V-~^fnWj:// / 



x < ^r^-' ' 



x ^_^ x / \ -v ,x 



/ X 

 __ -" x. 



FIG. 269. Schema of current distribution outside the body of 7'< pedo. (Cavendish.) 



succession or at longer intervals. In telephone observations 

 Schonlein found that both pitch and character of sound, from the 

 natural discharge of Torpedo, varied considerably. " If the sound 

 were expressed in letters, the vowels a\ e, or i must be selected, 

 never o or u." Brief shocks seem to be best expressed by R, 

 sung at different pitches. Longer discharges seem as a rule to 

 correspond with a higher pitch than brief shocks. 



The endurance of the fish is considerable. Du Bois-Eeymond 

 tested his-malapterurus every ten minutes, for two hours. "In- 

 cluding the removal of the fish to the experimental trough and 

 back again, it was excited 11-14 times; it yielded at least 

 twice or three times that number of shocks. During the series 

 of experiments the fish became visibly fatigued. It grew pale, 

 and at last responded only by a single shock when the cover 



