1905-6.] Excretion of Allanto'in in Thymus Feeding. 103 
To what extent is the increased excretion of allanto'in after boiled 
thymus due to the free purin bodies ? 
To test this question, a watery extract of 750 grins, of boiled 
thymus was prepared and fed to the dog. This, of course, con- 
tained the free purins, but not the nucleo-proteids. 
The result was the appearance in the urine of 0’365 grm. of 
allanto’in per 100 grm. thymus — an amount which corresponds 
closely with that which follows boiled thymus. This tends to 
show that the free purins are the source of the allantoin after 
boiled thymus is given. 
The Part played by Nucleins in the Production of Allantoin . — 
Since, in feeding with boiled thymus, the increased formation 
of allantoin appears to be due to the purin bodies, it seemed of 
interest to investigate how far the formation of allantoin may be 
varied by varying the amount of nucleins in the food. For this 
purpose the proportion of nitrogen in allantoin to the total 
nitrogen excreted was investigated on the following diets — oatmeal 
and milk, liver, raw pancreas, boiled pancreas, and beef. 
Food. 
Total 
Nitrogen. 
Allantoin 
Nitrogen. 
Allantoin 
Nitrogen, per 
cent, of total 
Nitrogen. 
Per 
cent. 
Per 
day. 
Per 
cent. 
Per 
day. 
1. Thymus raw, 950 grm. 
2-62 
4*9 
•940 
1-786 
36-4 
,, 950 grm. 
2-35 
14*1 
1 -408 
2-448 
17-3 
2. Thymus boiled, 790 grm. 
0-94 
12-3 
•051 
•663 
5-3 
3. Raw pancreas, 1 200 grm. 
2-0 
5'4 
•184 
•496 
»T 
,, 1000 grm. 
3-67 
9*1 
•520 
1-300 
14-2 
4. Boiled pancreas, 730 grm. 
1-7 
6-3 
•045 
T62 
2-5 
,, 780 grm. 
3*8 
14-0 
•046 
•165 
1-1 
5. Liver, 560 grm. 
2-5 
8*7 
T57 
•533 
6'1 
,, 560 grm. 
3-3 
8-4 
T47 
•367 
4-3 
6. Beef, 200 grm. 
4-0 
8T 
*093 
•186 
2 - 2 
7. Oatmeal 300 grin., Milk 
700 c.c., 
0-62 
6*3 
•040 
•404 
6-4 
53 53 
0-59 
5-2 
•036 
•313 
6-0 
” 
1-3 
3-54 
•141 
*364 
10-2 
