PLANT RESPONSE 



75 



minute of the application of chloral, is also extremely 

 well marked. 



U.U.- 



Before 



After 



FIG. 45. ACTION OF CHLORAL HYDRATE ON THE RESPONSES OF LEAF-STALK OF 



CAULIFLOWER 



Vibration of 25 at intervals of one minute. 



Response unaffected by variation of resistance. In 



order to bring out clearly the main phenomena, I have 

 postponed till now the consideration of a point of some 



Before ^ After 



FIG. 46. ACTION OF FORMALIN (RADISH) 



difficulty. To determine the influence of a reagent in 

 modifying the excitability of the tissue, we rely upon 

 its effect in exalting or depressing the responsive E.M. 



