THE POSITIVE RESPONSE 197 



The effect at the responding region of a strong excitation 

 transmitted through a short distance, or through a good con- 

 ducting channel, is negative ; the response is by negative tur- 

 gidity variation, contraction, fall of leaf, and electric change of 

 galvanometric negativity. 



The effect of feeble stimulus transmitted through a great 

 distance or through a semi-conducting channel is positive. The 

 response is by positive turgidity variation, expansion, erection of 

 leaf, and electric change of galvanometric positivity. 



