98 PLANT RESPONSE 



recovery in the case of the first two responses. But after- 

 wards it was not sufficient, so that recovery in the last three 

 instances was more and more incomplete, as seen by the 

 tilting upwards of the base-line of the responses (fig. 47). 



Table showing the Increased E.M. Variation 



PRODUCED BY INCREASING STIMULUS ' 



Tetanus. — Having now observed the effect produced by 

 single stimuli, we shall proceed to study the effects of similar 



Fig. 49. Genesis of Tetanus in Muscle 



Record to left shows incomplete tetanus, with moderate frequency 01 

 stimulation. Record to right shows tetanus more complete, with 

 greater frequency of stimulation (Brodie). 



stimuli when superposed. In muscle, we find that when 

 stimuli succeed each other with great rapidity, the effect of 

 the second stimulus becomes superposed on that of the first, 

 which has not had time to disappear. The result is a fusion 

 of effects, more or less complete. With moderate frequency 

 of stimulation we thus obtain incomplete tetanus, which, with 



1 Bose, Response in the Living and N011- Living, p. 53. 



