126 



NENOZO UTSURIKAWA 



Average amount of response for the first and second trials = 32 . 2 



Total number of failures to respond in the first and second trials = 51 



The following conclusions are indicated by the measurements 

 of amount of response: 



(1) 

 bred. 



(2) 

 (3) 

 (4) 



The response of outbred rats is far less than that of in- 



The response of females is greater than that of males. 

 The response is less in the second trial than in the first. 

 Individual and sex differences in amount of response far 



exceed strain differences. 



GENERAL BEHAVIOR DURING AUDITORY STIMULATION 



As an indication of the restlessness or general tendency to 

 activity as a result of auditory stimulation, the total length of 

 the response curve was measured by means of a chartometer. 

 This could be done only very inaccurately because of the many 

 slight changes in direction of the curve, but as in the case of 

 previous experiments, there is no reason to suppose that the 

 degree of accuracy varies with the strains or with the sexes. 



Measurements of restlessness were made for two conditions 

 of stimulation: (a) For separate auditory stimuli, the one 

 following the other after a stated interval and thus giving in 

 the records trial 1 and trial 2; and (b) for continuous auditory 

 stimulation instead of momentary. 



Table 6 presents the data of restlessness or general behavior. 



The principal results may be summarily stated thus: 



