54 



ANATOMY 



TABLE 38 



Percentage weight increase ifi 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) 



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 f er wnt formaldehyde made fresh for each lot of 

 animals killed (averages for two brains at each age) 



AGE OF HATS 



Maximum weight increase. 



