DIGESTIBILITY OF WHEAT BRAN. 13 
The figure 44.7 per cent reported for the digestibility of bran pro- 
tein results from averaging the figures obtained in five tests, while 
the figure 56.6 per cent reported for bran carbohydrate results from 
averaging eight experiments. The figure 44.7 per cent agrees closely 
with that obtained by Pannwitz,' who found that the protein of finely 
ground bran was 43.7 per cent digested. However, the value 51.4 per 
cent obtained by including only three tests is considerably higher 
than his figure. The figure 56.6 per cent for the digestibility of bran 
carbohydrate is materially lower than that of the carbohydrate of 
cereal flours or meals or the carbohydrate of the average mixed diet, 
a fact in accord with data reported by other observers. 
The figure 88.5 per cent obtained for the digestibility of the total 
fat of the diet is of interest. Except for the very little in the bran 
and in the potato and fruit the fat consumed consisted wholly of lard 
used in the preparation of the bread and butter eaten with the bread 
and potato. The digestibility of lard? had been found to be 97 per 
cent. In similar experiments? the digestibility of butter was found 
to be 97 per cent, and when it was included in a diet of meat loaf 
(containing hard palates of cattle), potato, crackers, sugar, and tea or 
coffee, the butter * was 95 per cent digested. In other experiments 
in which the diet consisted of bread, potato, fruit, butter (which 
supplied practically all the fat of the diet), sugar, and tea or coffee, 
the butter* was over 95 per cent digested. In more recent experi- 
ments in which butter® was eaten in conjunction with dasheen, milk, 
fruit, and tea or coffee, butter was over 96 per cent digested. It 
perhaps may be possible that the bran stimulated peristaltic action 
to such an extent that the fats, lard, and butter did not remain in 
the alimentary tract long enough to become as completely absorbed 
as they otherwise would. 
EXPERIMENTS WITH UNGROUND WHEAT BRAN. 
Seven experiments were made to determine the digestibility of the 
protein supplied by unground bran (flakes). The experiments were 
made in two groups, the first comprising experiments Nos. 409, 411, 
and 412 during the period March 13 to 16, inclusive, and the second 
experiments Nos. 436, 437, 438, and 439 during the period May 8 to 
11, inclusive. With one exception the same subjects assisted in 
both groups of experiments, and uniform experimental conditions 
1 Nihrwerth des Soldatenbrotes, Inaug Diss., Berlin, 1898, p. 123. 
2U. 8. Dept. Agr. Bul. 310 (1915), p. 21. 
*U. 8. Dept. Agr., Jour. Agr. Research, 6 (1916), No. 17, p. 647. 
“U. 8. Dept. Agr. Bul. 525°(1917), p. 8. ; 
5U. 8. Dept. Agr. Bul. 612 (1917), p. 8. 
