TISSUE CHANGES DURING STARVATION. 415 



rapidly, and subsequently more slowly ; and the reason for this 

 difference is that during the first three or four days the benefit of the 

 food last eaten continues, and the waste materials are eliminated 

 in proportionately large quantity. When the influence of the 

 food taken prior to the commencement of starvation has ceased, 

 the daily amount of materials eliminated remains nearly constant, 

 and the body-weight diminishes slowly until the animal's death. 



Adult animals commonly live until they have lost about half 

 of their normal body-weight. Young animals die when they have 

 lost about 20 per cent, of their weight. 



Roughly speaking, we may take the body of a man to be made 

 up of the following proportions of the more important textures : 



Muscles, 50 per cent. 



Skin and fat, 25 " 



Viscera, 12 " 



Skeleton, 13 " 



Seeing that the muscle tissue contributes such a large propor- 

 tion to the body-weight, we cannot be surprised that in starvation 

 the greatest absolute loss occurs in this tissue ; except in the case of 

 excessively fat animals. Next comes adipose tissue, which almost 

 entirely disappears, the absolute loss from it varying iu proportion 

 to the fatness of the animal at the beginning of the investigation. 

 The spleen and liver lose more than half their weight, and the 

 amount of blood is greatly reduced. The smallness of the loss 

 that occurs in the great nervous centres is very striking. They 

 seem to feed on the other tissues. 



The following table gives the approximate percentage of loss 

 which takes place in each individual tissue during starvation : 



Fat, 97.0 per cent. 



Muscle, 30.2 



Liver, 56.6 " 



Spleen, 63.1 " 



Blood, 17.6 " 



Nerve centres, 0. " 



With regard to the portals by which the various materials make 

 their escape, it has been found that practically all the nitro- 



