38 JOSEPH U. Y ARE ROUGH 



the sound stimulus. After the habitual response to the buzzer 

 had been built up an electric light was presented simultaneously 

 with the buzzer. It was hoped by this means to determine the 

 rate and number of trials necessary to transfer this response 

 from sound over to the simultaneously experienced light. During 

 the first series of 20 trials only a slight disturbance was shown, 

 the average percentage of correct response for the group being 86. 

 The animals continued to respond to the sound but in the presence 

 of light, a rather disturbing factor. The special series of 10 test 

 trials broke down the response. Only 24 per cent above the 

 minimum was made by the group, with two animals falling to 

 10 per cent above. Table XV contains the individual records. 



TABLE XV 

 Animal Training Trials % on Last 100 



49 ioo 93 



41 ioo 96 



43 ioo 91 



52 ioo 92 



Average ioo 93 



At the end of ioo trials each animal had made the association. 

 The transfer again was very rapid, and only a comparatively 

 small number of trials were necessary to make the association. 



The learning curves for these two groups, given in Fig. 9 

 depict the rapid growth of the association. The construction is 

 based on the per cent of right responses in both the regular series 

 and the special test trials. The first and each alternate point 

 thereafter is determined by the average per cent of right response 

 for the group in 20 regular training trials. The other points are 

 the average per cent of efficiency for the group in 10 special 

 test trials. From the curve it is seen that Group VII formed the 

 association by the end of 40 trials, for at no time after this did 

 the percentage of the group fall below 90. 



When these two groups are compared there are two points to 

 be noted, i) In both groups the percentage of right response on 

 the first 20 learning curves is practically the same. In these trials 

 the animals were reacting to an old stimulus but in the presence 



