422 Pellagra-Producing Diets. V 
the class of disease for which such protective substances exist, 
removes the necessity of postulating the existence of more than 
one indispensable substance in what we term water-soluble B, 
unless it shall be shown that rickets, the only other disease re- 
ferable to faulty diet, is comparable in its etiology with beri-beri 
and , xerophthalmia. The experiments reported in this paper 
support our contention that there are in reality but two ‘‘de- 
CHART 5. 
ficiency”? diseases, and but two physiologically indispensable 
unidentified dietary essentials. 
Chart 5. Lot 1,929.—In this chart are shown for comparison 
with the growth curves of young animals (Charts 1 to 4 inclu- 
sive) the curves illustrating the changes in body weight of grown 
rats confined to the diet of peas, flour, and cottonseed oil. ‘These 
were at the beginning of the experiment about 1 year old and in 
excellent condition, and capable, if fed a good ration, of living 
about 2 years longer. They were restricted to the diet of peas. 
