1913.] arising from Rivalry of Antagonistic Reflexes. 253 



switch. This being so we must consider the stimuli r. 13 and 1. 16 distinctly 

 unequal. Their separate effects on the preparation are shown at the beginning 

 of fig. 10. It is noticeable there that the rebound contraction after the 

 inhibition produced by r. 13 is greater than after that produced by 1. 16 ; also 

 that r.'s contractive effect on L muscle is better maintained than is l.'s on 

 K muscle. Yet this combination produces, as the figure shows, good stepping 

 in one of the muscles. Now this fig. 10 is from the same experiment as furnished 



r 14 r 13 



fig. 1 and the combined stimuli in fig. 1 are , . And .=-1— must be con- 

 b ° 1. 17 1. 16 



sidered less equal than j— y et the rhythmic stepping of the left muscle in 



fig. 10 is as good or better than that in fig. 1. Now the stimuli used in fig. 1 

 were themselves unequal, not merely on the face of their scale values but as 

 tested on the preparation at the time. Fig. 11 shows the effects of these two 

 stimuli when employed separately ; the tonic effect is obviously not equal but 

 also not far from equal ; but (fig. 12) the rebound is greater after inhibition 



Fig. 12. — Right knee extensor (R.V.) and left (L.V.) isolated and reacting reciprocally to 

 reflex stimulation of each peroneal afferent ; r.p., right peroneal, l.p., left peroneal. 

 Time above in fifths of seconds. Decerebrate cat. 



T 2 



