409 



shall most likely be compelled in my further investigations to restrict 

 myself to artificial transitions of poisoned frogs' hearts, and, when 

 doing so, I shall at the same time register the action-currents. 



1 am likewise in possession of beautiful examples of the slow 

 transition to the halved rhythm of unpoisoned frogs' hearts. One 

 example of these is reproduced in the figures 2, 3, 4, and 5. 





be 



27 



Proceedings Royal Acad. Amsterdam. Vol. XX. 



