WALTER E. GARREY 



167 



that the drop in the rate of CO2 production follows abruptly upon the 

 incidence of inhibition but that the return to the normal after inhibi- 

 tion is a much more gradual process, indicating a persistence of the 

 inhibitory state after the cessation of stimulation of the inhibitory 

 nerves. The recovery to the normal rate of CO2 production is 

 slower the greater the degree of depression during inhibition. 



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Fig. 1. Curves showing the percentage rate of CO2 production compared with 

 normal = 100 per cent. The numbers 1, 2, 3, and 4 correspond to the experiment 

 numbers in Table I. The horizontal levels opposite these numbers show the 

 average depression of COo production during the period of inhibition which in 

 each case continued for the time required to make the determination (c/. Table 

 I). The readings for the curves of recovery are designated for each experiment 

 by the character at the end of the inhibition period. Recovery time in seconds. 



It is significant that the recovery process involves a return merely 

 to the previous norm and that there is no subsequent increase in the 

 rate of CO2 production, no acceleration or after-augmentation, so 

 that experimental evidence lends no support to the view that inhibi- 

 tion as exemplified in these nerve cells is accompanied by any con- 



