20 



HARRY H. WYLIE 



^00- 



Figure III 



75- 



Figure IV 



Curve 22 (Figure III) is an individual curve from Group One. Curve 25 (Figure 

 IV) is an individual curve from Group Two. The horizontal lines represent the per- 

 centage of correct responses. The vertical lines represent the number of series of 

 20 trials each. In lettering, — A is the end of the learning process with light, B is 

 the first control series, C is the second control series, D is the beginning of training 

 with the sound, S (in Curve 25) is the beginning of simultaneous light and sound. 



