114 NENOZO UTSURIKAWA 



of the position of an individual in the cage or nest box; (2) of 

 the relative positions of the two individuals, male and female, 

 in the cage; (3) of the degree of activity in the cage; (4) of sav- 

 ageness, viciousness, or tendency to bite. The experimental ob- 

 servation includes (1) measurements of quickness of response 

 to auditory stimuli; (2) of amount of movement in response to 

 the same stimuli; (3) of general behavior (restlessness) during 

 stimulation. 



These several varieties of observation will now be reported in 

 tabular form, with scant discussion. 



POSITION OF RAT IN CAGE 



The animals were kept in rectangular, all-wire cages, the 



floor dimensions of which were 16 inches by 14 inches. A single 



pair of individuals, either outbred or inbred, was kept in a cage. 



When the writer came into the animal room to feed the rats, 



many of them would, as a rule, come forward in expectation of 



food, but some would remain at the back of the cage or retreat 



to the distant portion of the cage as the experimenter approached. 



Some came forward singly; others, together. Sometimes the 



individuals were found lying together in the cage ; at other times 



they were observed to be distant from one another. The data 



of table 1 concern, first, position of the two animals, male and 



female, in the cage when the experimenter entered the room; 



and second, the positions of male and female with relation to 



one another. 



TABLE 1 



