TABLE 6 



Shoifjng, by generations, the average body ivcight at different ages of 57 males be- 

 longing in the seventh to the fifteenth generations of the B series of inbred rats 



* One record only 



TABLE 7 



Showing, by generations, the average body weight at different ages of 93 females 

 belonging in the seventh to the fifteenth generations of the B series of inbred rats 



* One record only. 



14 



