54 



ANATOMY 



TABLE 38 



Percentage weight increase in rats' brains, each kept for four weeks in 40 cc. of a 

 neutralized solution of 4 per cent formaldehyde made fresh for each lot of animals 

 killed (averages for two brains at each age) 



1 Maximum weight increase. 



TABLE 39 



Percentage weight increase in rats' brains, each kept for four weeks in 40 cc. oj 

 non-neutralized solution of 4 per cent formaldehyde made fresh for each lot of 

 animals killed (averages for two brains at each age) 



AGE OF RATS 



1 Maximum weight increase. 



