634 COMPARATIVE ELECTRO-PHYSIOLOGY 



motive variation, the abnormal response 

 is seen to be converted into normal after 

 tetanisation. It will be noticed, in all 

 these cases, that the antecedent molecular 

 transformation, on which the conversion 

 from abnormal to normal response 

 depends, is also shown independently, 

 by the shifting of the base-line of the 

 record in the direction of the normal 

 response that is to say, upwards. 



In the next series, again, in fig. 393, 

 is shown the effect of tetanisation in 

 enhancing feeble normal response. This 

 moderate normal response, it will be 

 remembered, is characteristic of the 

 molecular condition, just above the 

 point of transition from abnormal to 

 normal. In (a) is seen the enhancement 

 of mechanical response in nerve of fern. 

 In () we have the enhanced electro- 

 motive response of frog's nerve. In (c) 

 a similar enhancement of electro-motive 

 response is shown in plant nerve. In (d) 

 we see the enhancement of response 

 after tetanisation in aluminium powder 

 by the method of resistivity variation, 

 the stimulus employed being Hertzian 

 radiation. In (e) the method of record 

 is also by resistivity variation, in a 

 selenium cell, under the stimulus of 

 light. And finally, in (/) are given the 

 responses of platinum wire, under the 



FIG. 393. Series showing how Tetanisation enhances Normal Response 

 in the B Phase 



a, Mechanical response of frog's nerve ; t>, Electro-motive response of 

 frog's nerve ; r, Electro-motive response of plant-nerve ; </, Response 

 by resistivity variation in aluminium powder ; , Response of selenium ; 

 /, Electro-motive response of tin. 



