102 Proceedings of Royal Society of Edinburgh. [sess. 
Table III. —continued. 
Boiled Thymus. 
Observations. 
Allantoin. 
Allantoin per 
100 grm. 
Thymus, less fat. 
Food. 
Per cent. 
Per diem. 
1. Retriever 
bitch 
*314 
1*480 
•251 
684 grm. 
2. „ 
*431 
1*568 
•267 
680 grm. 
3- „ 
•466 
3*032 
•325 
1080 grm. 
4. 
I 
•311 
4-977 
•498 
1160 grm. 
Average, 
2-7 
•335 
901 grm. 
The effect of the raw thymus is thus double that of the boiled. 
2nd. By studying the proportion of the nitrogen of the urine 
to the nitrogen in allantoin after feeding on raw, and after feeding 
on boiled, thymus gland. 
Table IY. 
Proportion of Total Nitrogen to Allantoin. 
Obser- 
vations. 
Total Nitrogen. 
Allantoin Nitrogen. 
Food. 
Per- 
cent. 
Per 
diem. 
Per 
cent. 
Per 
diem. 
Per cent, 
of total 
Nitrogen. 
Raw Thymus. 
1. Setter 
2-62 
4-984 
•94 
1-786 
*36*4 
950 grm. 
2. „ 
2-35 
14-159 
•408 
2-448 
17-3 
950 grm. 
;i j /: 
Boiled Thymus. 
3. ,, 
•946 
12*3 
•051 
•663 
5*3 
790 grm. 
* The correctness of this figure is further indicated by the fall in the 
percentage of nitrogen in urea from about 84 to 57. 
The percentage of allantoin nitrogen after thymus feeding in 
the case of the setter is thus 36 - 4 per cent., and 17*3 per cent, 
upon a diet of raw thymus gland, and 5 '3 per cent, in the case of 
boiled thymus gland. 
These observations appear to negative the view that the allantoin 
found is simply derived from the nucleins and purins of the thymus. 
