32 



CHARLES A. COBURN 



the sixth test is greater in each case than that for the fifth 

 test of the same group, (First section of tables 19, 21, and 23), 

 due, without doubt, to the absence of any handling by the ex- 

 perimenter during the 27 or 28 days intervening since the fifth 

 test, yet only in the case of the younger mice of F2b is the aver- 



TABLE 20 



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



at Usual Times 



Distribution of mice 

 in grades: 



Average number tests, 4.89 

 Range of 



tests, 3-5 First test. 



Average age in days: 

 First 



test, 34.52 

 Last test, 65.15 



19 Fab Males 

 and Females 



Average 1 and 2 

 Average all 



Average 3, 4 and 5. . 

 Last test 



Average number tests, 5 

 Range of tests, 5 First test 



Average age in days: 



First 



test, 34.4 



Last test, 66.3 



Average 1 and 2 



9 Fab Males 



Average all 



Average 3, 4 and 5 . 

 Last test 



Average number tests, 4.77 

 Range of 



tests, 3-5 First test. 



Average age in days : 

 First 



test, 34.64 

 Last test, 62.22 



Av. 



lOFgb 

 Females 



Average 1 and 2 . . 

 Average all , 



Average 3, 4 and 5. 

 Last test 



4.0 



3.8f 

 3.18 



2.69 



2.42 



3.7 



3.45 



2.98 

 2.66 

 2.4 



4.33 



4.37 



3.41 



2.72 

 2.44 



10 



SAVAGENESS 



Distribution of mice 

 in grades: 



Av. 



3.94 



4.18 



3.18 



2.49 

 1.78 



3.8 



3.9 



3.12 



2.6 



2.3 



4.11 



4.5 



3.25 



2.36 

 1.22 



12 3 4 5 



12 



age grade for wildness in the sixth test of Group 2 greater than 

 that for wildness in the fifth test of the corresponding Group 

 1 (table 20). The average grade for savageness for the sixth 

 tests of each Group 2 is greater than that for the fifth test of 

 the corresponding Group 1. 



