HEREDITY OF WILDNESS AND SAVAGENESS IN MICE 



In order to avoid any effect which a change of surroundings 

 and a possible change of temperature or light may have upon 

 the behavior of the mice, all testing was done in the room occu- 

 pied by the mice. The cage containing the individuals to be 

 be examined was placed upon the testing table which was 

 located, as a rule, in one corner of the room. Upon the table 

 were also placed paper, pencil, paper punch for marking the 

 mice, and a pair of placental forceps over the jaws of which 

 had been placed soft rubber tubing in order to lessen the pres- 

 sure and also the chances of injuring the tail of the mouse which 

 required its use in catching. The gloves worn by the experi- 

 menter while testing were of kid of medium thickness. 



Removing the mouse from the nest was done, when the 

 mouse was hiding in the nest, by gently pushing back with 

 the left hand the shredded tissue paper of the nest until the 

 tail was exposed and then, grasping the tail between the thumb 

 and forefinger, the mouse would be equally as gently pulled 

 from the nest and at the same time placed upon the palm of 

 the hand by turning the palm upward. In this way the mouse 

 could often be removed without greatly disturbing it. When 

 the smaller Bussey Institute cage was used, since the door was 

 so small, often the tail when exposed had to be grasped by the 

 placental forceps and thus the mouse pulled from the nest and 

 placed upon the palm of the hand. When the mouse to be 

 removed was not hiding in the nest the forceps were used to 



