324 



GROWTH OF CHEMICAL CONSTITUENTS 



TABLE 180 



Showing the content of total nitrogen as well as non-protein nitrogen in the entire 



brain oj the albino rat at different ages 



50 



100 



150 



2D0 



250 



300 



350 



400 



Chart 58. Showing the number of milligrams of non-protein nitrogen per gram 

 of the dried brain at different ages. The chart shows also the proportional value 

 of organic e.xtractives together with inorganic salts in the brain of the albino 



rat, as determined by W. Koch and M. L. Koch ('13). Non-protein 



nitrogen, X organic extractives and inorganic salts. 



