Eesearches on the Discharge of the Electric Organ. G7 



previous section, and tliat whicli cannot l»e recovered is due to 

 the alteration in the organ or in the nerve. Of course, the interval 

 hetween two consecutive stimuh is ^'ery large compared with the 

 period of recovery discussed in the former section, hut there is still 

 a fatigue, for not only small residuals of tlie fatigue may accumulate 

 in such cases, hut also a part of the nerve trunk may still he in 

 deep fatigue on account of the stimulation hy tlie discliarge of the 

 higher oi'der, when a succeeding stimulus is given. As we re- 

 marked in the preceding section, when the fatigue advances, the 

 hminal vahie for the maximal stinudus increases in nerve, so that 

 the stimulus of the given magnitude, which is sufficiently maximal 

 at the outset of the fatigue, hecomes submaximal, and a little 

 N'ariation in its magnitude may cause the discharge of a difïerent 

 magnitude. May not this l)e the cause of the irregularity of the 

 discharge in the tired state ? 



In regard to the increase of the contraction at the outset of 

 fatigue in nuiscle, Fröhlich interprets the phenomenon as the ap- 

 parent efïect of the prolongation of the wa\'e length of the contraction 

 propagating through a muscle. He thinks that, the fact that the 

 same phenomenon could not l)e observed in negative A'ariation, 

 gives support to his theory. lUit since a similar interpretation 

 fails to apply in our case, it is i)robal»ly incorrect. In view of our 

 experimental results, it seems to me that the phenomenon is 

 analogous to the abnormal increase of the electromotive force of 

 the second discharge discussed in the preceding section. In that 

 section, we explained the phenomenon as the efïect of the super- 

 position of the second discharge on the secondary discharge. Here, 

 of course, the principal discharge evoked by the succeeding 

 stimulus is very far from the secondar}^ discharge, l)ut it may be 

 superposed with a discharge of one of the liigher orders. To 

 express my idea clearly, suppose a discharge followed by a series 

 of higher orders, to be CN'oked by one of the stimuli separated 

 by a fixed interval of time as in the experiment. When the 

 fatigue advances, the modal latent period is prolonged gradually, as 

 may be observed in tlie fatigue investigations of the other form, 

 and the secondary, the tertiary discharge et seq. delay in propor- 



