12 



CHARLES A. COBURN 



mice were 110 days old. The wildness and savageness had 

 evidently been counteracted by the taming effect of the daily 

 presence of the experimenter while feeding and cleaning the 

 cages, and the handling during the five tests. The degree of 

 savageness was only about half as great as that of wildness 

 and did not persist as long, since after the second test the grade 

 for savageness was in no case above 0. Another point which 

 should be mentioned here but which is not shown in the table 

 is the difference in the degree of wildness and savageness of 

 the males and females. If the average of all the five tests is 

 used as a criterion, the females were about twice as wild and 

 savage as the males since the average grades for wildness and 



TABLE 2 

 Summary of Results for One Litter of Offspring of Mice from Bussey Institute 



Average number tests, 5 



Range of tests, 5 First test 



Average age in days : 



First test, 46 Average 1 and 2. 

 Last test, 110 



Average all 



5 mice 



(3 males and Average 3, 4 and 5 . . . 

 2 females) 



Last test 



savageness, respectively, were 1.8 and 0.6 for the females in 

 contrast with 0.73 and 0.33 for the males. 



As a result of this evidence of impurity in the tame mice, 

 2 males and 10 females were obtained from Miss Lathrop. 

 Before these were used, however, a mating was made from them 

 and the offspring tested as in the previous instance. There 

 was not a mouse in any of these tests which received a grade 

 above in either wildness or savageness. The proof of the 

 purity of the tameness and non-savageness of these young 

 mice (table 1, nos. 529 to 533 inclusive), and their parents was 

 considered so conclusive that there was no hesitation in assum- 

 ing an equal purity in the. remaining 10, 



