316 



GROWTH OF CHEMICAL CONSTITUENTS 



old, Hatai ('17) has sought to determine the composition of the 

 milk in this animal. The average results are given in table 173. 



2. Osseous system. The gross chemical composition of the 

 humerus and femur in the male and female albinos, at two ages 

 has been determined by Hammett ('23). Tables 174 and 175 

 show the values with the statistical constants. 



TABLE 172 

 Calcium in blood serum. Three male mature rats on a mixed diet 



CALCIUM IN 100 CC. OF SERUM 



c 



D 



E 



11.1 

 11.1 

 12.0 



TABLE 173 ' 

 Composition of rat milk (Hatai '17) 



COMPOSITION 



The differences according to age are evident. The differences 

 according to sex are in part at least to be referred to the more 

 rapid development of the female. 



In a study on the salt content of the bones (Hammett, ; 23) 

 found the relations in the normal humerus and femur to be as in 

 table 176. 



