THE METABOLISM OF THE PURIN BODIES 401 



periods the following diets were taken : Period I. A diet of 

 250 grm. beef, and 120 grm. ham, with potatoes, bread, cheese, 

 butter, &c. total nitrogen, 16*8 grm. Period II. Instead of flesh, 

 ten eggs and a litre of milk were taken; the other constituents 

 were the same as in Period L, the quantities being slightly varied. 

 This diet contained no purin-yielding food total nitrogen, 16- 8 

 grm. Period III. The diet contained the same substances as that 

 of Period II., only much less milk and eggs, so that the total 

 nitrogen content was 9 '3 grm. Rice was added to bring the calories 

 to the same level as in Period II. Period IV. A purely vege- 

 table diet (500 grm. potatoes, 100 grm. rice, bread, butter, and 

 sugar), containing the same amount of nitrogen as Period III. 



For convenience we may describe these diets as follows : 



Period I. Meat diet of high nitrogen content. 



Period II. Milk, cheese, and egg diet, of equally high nitrogen 

 content. 



Period III. Milk, cheese, and egg diet, of low nitrogen content. 



Period IV. Vegetable diet of equally low nitrogen content. 



Each of these periods lasted four days, and during them the 

 total nitrogen and total purin excretions were measured. The 

 following table shows the results. 



TABLE I 



2c 



