T. B. Osborne and A. J. Wakeman V7 
phorus of the serum is organically combined and that some of 
this, at least, is precipitated by ferric chloride under the above 
conditions, for a sample of the carniferrin precipitate which we 
obtained, when dissolved in cold dilute nitric acid, gradually de- 
posited a voluminous light yellowish precipitate on standing at 
room temperature with no evidence of the formation of the char- 
acteristic yellow ammonium phosphomolybdate, whereas an- 
other sample did not give the yellow precipitate till boiled for 
some minutes and this gradually increased on continued boiling 
just as if phosphoric acid were being liberated by hydrolysis. 
That milk serum, freed from calcium phosphate by neutralizing, 
still contains phosphorus in organic combination is made prob- 
able by the fact that when this is acidified and boiled a precipi- 
tate of calctum phosphate forms when the solution is again made 
alkaline. 
In view of these facts it is our opinion that the nucleon which 
Siegfried obtained from milk was probably a mixture of un- 
coagulable protein and some still unidentified organic substance 
which yields phosphoric acid on hydrolysis. 
An Alcohol-Soluble Protein in Mulk. 
From the alcoholic washings of the large quantities of casein 
which have been made in this laboratory we have isolated several 
hundred grams of a protein which closely resembles gliadin of 
wheat in its solubility in alcohol of 50 to 80 per cent. Although 
the actual amount of this protein in milk is extremely small, the 
large quantity obtained as a by-product from the necessary 
processes incident to our feeding experiments seemed to justify 
a special investigation of its physical and chemical peculiarities. 
The results of this investigation, which will form the subject 
of a subsequent paper, have shown that this protein is an original 
constituent of milk and not a derivative of any of the other 
proteins contained therein. Since preparations have been ob- 
tained so far free from each of the other milk proteins that no 
evidence of such contamination could be detected by the anaphy- 
laxis reaction, we feel justified in regarding it as a new constituent 
of this important food product. 
THE JOURNAL OF BIOLOGICAL CHEMISTRY, VOL. XXXIII, NO. l 
