PFLUGER'S LAW. 235 



With a weak current the kathode is alone operative. With 

 a medium one both are operative as stimuli, whilst at the 

 same time the anode is not powerful enough to block the ex- 

 citation due to the katelectrotonic stimulus. With the strong 

 ascending C, the anode blocks at make, but stimulates by its 

 fall at break. 



In the case of the strong descending, the kathode has 

 nothing to block its action at make, but at break the fall 

 of excitability on the disappearance of katelectrotonus is. 

 held to block the stimulus due to the fall of anelectrotonus. 



