262 RESEARCHES ON IRRITABILITY OF PLANTS 



And finally, with a current of 10 micro-amperes the typical 

 response of Type IV. was obtained — namely, Km Kb Am Ab. 

 These results are shown in the following tabular state- 

 ment : — 



Table II. — Effects of Currents of Increasing Intensity 

 on Leaflets of Biophytum 



These results were confirmed by fifty sets of experiments 

 on different specimens of Biophytum. 



Leaflets of Averrhoa carambola 



These leaflets are, as already explained, relatively 

 insensitive and therefore require a higher e.m.f. with higher 

 current. With these specimens also I obtained, as before, 

 the four types of effects in their usual sequence. Thus in a 

 given experiment a current of 4 micro-amperes gave Km, 



Table III. — Effects of Currents of Increasing Intensity 

 on Leaflets of Averrhoa carambola 



the effect indicative of Type I. ; when the current was now 

 raised to 11 micro-amperes excitation at Km Ab, constituting 



