THE RELATION OF DIET TO DISEASE 443 
tive tube, of the storage organs, of the organs of elimina- 
tion and of the endocrine glands predominate. Their 
diet is low in carbohydrates and, at times, in fats and very- 
high in protein. Bone supplies the inorganic salts, which 
in this Garden is fed only to the larger mammals. The 
carnivorous birds get their inorganic supply from mice 
which are eaten entire. The carnivores are as a rule large 
and are given to active fighting or to long flights. In the 
wild, very probably there are long periods between feasts, 
while in captivity the food is always plentiful and regu- 
larly supplied. This regularity added to the lack of exer- 
cise, particularly among the larger animals, must lead to 
excessive demands upon the storage and eliminating 
organs. Storage is always promoted by rest and liberal 
diet, and cleared away by exercise and starvation. The 
life of these birds and mammals, moreover favors inac- 
tivity of the bowels, which, together with the highly putre- 
factive diet adds another serious factor to a problem 
which in gardens is almost insurmountable. 
Ikregularities of Caebohydrate Metabolism. 
The carbohydrates are derived from the glucose and 
glycogen of the meat and from the protein molecule. They 
are absolutely less than in the diet of herbivores but be- 
come a factor in the disorders of this group because of 
the lack of exercise and the regularity of feeding. In 
digestion the carbohydrate becomes available for absorp- 
tion and bacterial growth in the upper small intestine 
and appears on the other side of the intestinal wall as 
blood glucose in which form it is burned for energy or 
stored as glycogen for the future maintenance of the 
blood glucose. 
The blood of different animals has a glucose concentra- 
tion between 0.05 -0,1 which for each species is quite con- 
stant, as it is regulated by the coadaptation of four 
factors: combustion, fermentation of glycogen, forma- 
tion of fat, and elimination from the kidney. In excessive 
