New York AGRICULTURAL EXPERIMENT STATION. 105 
small amounts of soluble organic phosphorus but elaborate examina- 
tions of large quantities of milk, urine and feces during a time when 
the animal was receiving an excessive amount of phytin, failed to 
reveal its presence even in minute proportions. ‘These facts, to- 
gether with the failure to cause a cleavage of phytin through the 
action of enzyms, indicate that this body was absorbed, metabolized, 
and its phosphorus excreted, largely through the feces, in inorganic 
forms. : 
The observations of other experimenters show clearly that the 
presence of any compound in the feces is not proof that it has not 
been absorbed into the body cavity. Bergman®’ demonstrated 
that when glycero-phosphoric acid is injected subcutaneously into 
a sheep the phosphoric acid is excreted in the dung. Mendel & 
Thacher®? have also shown that mineral compounds that are ab- 
sorbed from the intestinal tract may afterward appear in the feces. 
There is a growing evidence among physiologists that the ali- 
mentary canal is a channel for the excretion of something more 
than the substances which have failed of digestion and absorption, 
and consequently that the percentage of digestibility of certain 
compounds is not measured by the difference between the amounts 
of these compounds in the food and in the feces. It seems to be 
practically established that the claim made by Rubner®® that the 
loss through non-absorption of the mineral constituents of whole 
wheat flour as compared with patent flour is much greater in the 
case of the former, does not rest on a sound basis, an observation 
which applies equally well to all conclusions reached in a similar 
manner. A comparison of the mineral compounds of the con- 
stituents of the food with those in the fecal discharge evidently can 
not be depended upon as a means of ascertaining the availability 
and usefulness of the ingested mineral compounds. 
The foregoing data include many interesting facts, but do not 
justify final conclusions concerning the main points under investi- 
gation. On the basis already established, however, the authors plan 
to continue the inquiry with the hope of reaching a more complete 
solution of the problems involved. 
*" Jahresber. Agr. Chem., 3d F., 42 354. Igor. 
* Amer. Jour. Physiol., 11: 5. 1904. 
“Zett. Biol., 19: 45, 1883. 
