36 



CHARLES A. COBURN 



The decrease in both wildness and savageness for hybrids 

 Fib (tables 18 and 19) compares very favorably with the older 

 mice of F2b (tables 22 and 23), except that the latter show a 



TABLE 24 

 General Summary of Tables 18, 19, 20, 21, 22, and 23 



slightly greater decrease than the former. Between these 

 two, however, and the younger mice of F2b (tables 20 and 21) 

 there is a striking difference. Considering the difference be- 

 tween the first and last tests for wildness and savageness in 



