EFFECTS OF INBREEDING ON BODY WEIGHT 



41 



TABLE 17 

 Showing the coefficients of variation with their probable error for the body weights 

 at different ages of male and female rats belonging to three series: (1) eight litters 

 of the fifteenth generation of inbreds (series A, B); {2) thirteen litters of selected 

 stock; (3) a single litter of selected stock 



A^comparison of the coefficients for the males of the combined 

 series (table 15) with the corresponding coefficients for stock 

 males (table 17) shows that inbred males tended to be somewhat 

 moreVariable in body weight than stock males up to sixty days 

 of age, which is the period of maximum variability for both 

 groups. From this age on, however, stock males were appar- 

 ently more variable than inbred males. The average coefficient 



