416 ~ Pellagra-Producing Diets. V 
while Lot 1,021, Chart 2, and Lot 1,022, Chart 3, demonstrate 
that the content of the dietary factor, fat-soluble A, is not 
the factor limiting growth. No matter how well the proteins 
of this diet are supplemented with purified protein addition, 
with or without increasing the content of the diet in fat-soluble 
A, growth cannot take place unless the elements sodium, chlorine, 
and calcium are added. We have shown in the first (12) and 
fourth papers (15) of this series that these are the only inorganic 
elements which are required to be added to any of the seeds in 
order to make them dietetically complete, as far as the mineral 
content is concerned. Compare Chart 1 with Charts 2 and 3. 
These groups of rats developed very rough sealy tails, and 
numerous bleeding points covered the surface. The ears were 
thickened .and on the margins scabs developed. There was a . 
cutaneous horn on the nose of each rat. These signs of patho- 
logical changes on the skin are common in our rat colony in ani- 
mals fed certain types of faulty diets. They are not the unfail- 
ing accompaniment of diets which cause debility even of a severe 
character. We have not yet analyzed with sufficient thorough- 
ness the exact nature of dietary faults which induce these changes. 
There was no diarrhea in any of our rats on the diets described 
in this paper. Neither did we observe infection in the oral and 
intestinal mucosa. 
Lot 1,916 A.—The diet in Period 1 could not support any 
growth. In Period 2, they received in addition sodium chloride 
and calcium carbonate. The salt additions induced a slight 
response with growth for 6 to 8 weeks, followed by decline. 
Lot 1,021, Chart 2, shows the necessity of adding these salts, if 
growth is to take place; Lot 1,023, Chart 3, shows that no others 
are necessary to enable the animals to grow at the normal rate. 
The inorganic content of this diet is, therefore, the first limiting 
factor in preventing growth. 
The peas were soaked in water, then heated in a sterilizer at 
15 pounds’ pressure for 1 hour, and dried in a current of air at 
about 70°C. Gold Medal flour and a commercially bleached cot- 
tonseed oil were employed. The animals. were given distilled 
water, and according to our general custom, were furnished 
water containing iodine in potassium iodide once each week. 
Chart 2. Lot 1,916 B.—In Period 1 these rats received the 
é 
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