140 COMPARATIVE ELECTRO-PHYSIOLOGY 



Hence the positive effect is no longer completely masked. 

 Its existence is now seen as a preliminary downward 

 twitch in a di-phasic response, in the case of the fourth 

 and succeeding records, after the application of KHO. In 

 fig. 98, a stronger, namely a 5 per cent, solution of KOH, was 

 used. And here, by the almost complete abolition of the 

 excitatory factor, the response has undergone an apparent 

 conversion to positive ; this positive response is, however, 

 subsequently abolished by the death of the plant. 



