326 GROWTH OF CHEMICAL CONSTITUENTS 



The value for the percentage of water (table 183) is similar 

 in the several divisions and nearly as high as that in the brain 

 and cord at birth. Thus the water-solids relation is not signifi- 

 cantly altered in older rats, if the lipoids are excluded from 

 consideration. These results further confirm the conclusion of 

 Donaldson ('16) that the reduction of the percentage of water in 

 the nervous system with advancing age is due mainly to the 

 accumulation of myelin in it. 



GROWTH IN CHEMICAL CONSTITUENTS I REFERENCES 



In the body as a whole. Buckner and Peter, '22. Bunge, '02. Cameron, '14 

 Hatai, '17. Heymann, '04. Inaba, '11. Korenchevsky and Carr, '23 a. Lan- 

 der, '15. Lund, Shaw and Drinker, '21. McCollum, '09. Mendel and Daniels, 

 '12. Pembrey and Spriggs, '04. 



Osseous system. Hammett, '23 g. Toverud, '23. 



In the nervous system, von Bibra, 1854. Hatai 17 a. Koch, M. L., '13. 

 Koch and Mann, '09. Koch and Koch, '13, '13 a. 



