1913.] Contributions to the Biochemistry of Growth. 305 



about equal quantities, the food was removed from the cage and a given time 

 afterwards the animals were killed by breaking the neck. In every case a 

 normal and a tumour-bearing animal were killed at the same time. 

 The results obtained are given in Table II. 



Table II. 



Hours 

 after 

 last 

 meal. 



Tumour rats. 



Normal rats. 



Diet. 



Weight 



of 

 tumour. 



Weight 

 of 

 liver. 



Liver 

 glycogen. 



Weight 

 of 

 liver. 



Liver 

 glycogen. 





g™i- 



grm. 



per cent. 



grm. 



per cent. 





3 



6-5 



6-3 



0-62 



3-7 



0-66 



Meat. 





5-5 



7-4 



1 -46 



5-8 



1 -68 



Bread and milk. 





9-2 



4-7 



1-81 



4-4 



3 -58 



Bread and milk, fasting 24 hrs. 















previous to last meal. 



7 



9 5 



5 -0 



<0-2 



4-5 



0-51 



Bread and milk. 





5 



4-2 



<0-2 



4-5 



2 -43 



)> j) 





9 5 



5-0 



<0'2 



4-8 



2 24 



>> >i 











4-5 



1 -52 





17 



4-0 



6-7 



<0-2 



4-8 



<0'2 



Meat. 



24 



12-0 



4-7 



<0-2 



3-8 



<02 



Bread and milk. 





4-2 



4-0 



<0-2 



2-6 



<0-2 





The results show that a definite difference exists between the glycogen 

 metabolism of a normal and a tumour-bearing animal : the glycogen disappears 

 more rapidly from the liver of a Uimour-bearing rat than from the liver of a 

 normal rat. 



This result is in complete agreement with some observations on the gaseous 

 metabolism, which were carried out by one of us in 1908 (1), and which have 

 been confirmed since by Chisholm (3). It was found then that after a meal 

 a tumour-bearing animal returns to the fasting state more rapidly than 

 a normal animal. 



These observations, taken together with those made four years ago by 

 Cramer and Pringle on the nitrogen metabolism of tumour-bearing rats, 

 throw some light on the metabolic conditions of an animal in* which processes 

 of active growth are taking place. Cramer and Pringle found that a tumour 

 transplanted into young growing rats grows to a considerable size without 

 interfering with the growth of the animal. As the tumour grew the 

 nitrogen excretion of the host fell, so that there was a " sparing " of the 

 protein metabolism. The present observations show that this " sparing " is 

 associated with an increased carbohydrate metabolism. 



In these experiments on the nitrogen metabolism it was necessary to 

 maintain the animals on a constant nitrogen intake. It might be argued that 



