34 



CHARLES A. COBURN 



have been brought together in table 24. The headings at the 

 top show the different hybrid generations and the groups. 

 The headings at the side indicate (a) the table in which the 

 complete results of a group may be found, (b) the number of 

 mice in each groups, (c) the average age in days of the group at 

 the first test, the fifth test, and the difference between these 



TABLE 22 



Summary of Results of Group 1, Second Generation Hybrids, Fo, of Series B, Tested at 



Usual Times 



Distribution of mice 

 in grades: 



Av. 1 2 3 4 5 



SAVAGENESS 



Distribution of mice 

 in grades: 



Av. 



4.05 



4.35 

 3.49 



2.92 



2.58 



4.0 



4.42 



3.42 



2.76 

 1.85 



4.1 



4.3 



3.6 



3.13 

 3.1 



1 



ages, or in other words, the number of days required for the 

 tests in each group, {d) the average grade of wildness for the 

 first test, for the fifth test, the difference between the first and 

 fifth, the average of the first and second tests for wildness, the 

 average for wildness as shown by the third, fourth, and fifth 

 tests, and the difference between these two averages. Imme- 



