T. B. Osborne and A. J. Wakeman 13 
extract was treated with ether, which dissolved all but a little 
finely divided white substance. This latter had the appearance 
characteristic of the diaminophosphatide which we previously 
obtained under similar conditions from the mixed phosphatides 
extracted from the coagulated milk protein. Without filtering, 
the ether solution was poured into acetone and yielded a pre- 
cipitate which contained phosphorus equal to about 0:0800 gm. 
of phosphatide, equivalent to 2.2 per cent of the lactoglobulin 
as calculated from the nitrogen in the magnesium sulfate precipi- 
tate after extraction with alcohol. 
The preparation of lactoglobulin coagulated by heat and ex- 
tracted with alcohol contained 0.24 per cent of phosphorus, 
which would correspond to about 7 per cent of phosphatide if all 
of the phosphorus were present in such substances. Owing to 
the presence of the relatively large amount of magnesium sulfate 
it was not possible to determine how much of this phosphorus 
belonged to inorganic phosphates, but the repeated precipitations 
with ammonium sulfate ought to have removed this completely. 
As just noted, the alcoholic extract of the uncoagulated lacto- 
globulin contained phosphorus equal to 2.2 per cent of the 
globulin. In this respect a similarity exists with the vitellin 
from hen’s eggs which on treatment with alcohol yields over 
20 per cent of substance, much of which is phosphatide, while 
the thoroughly extracted protein contains about 1 per cent of 
phosphorus. It is possible that lactoglobulin is a similar lec- 
ithalbumin, or is a mixture of proteins, one or more of which 
belongs to this group. Further investigations are needed before 
final conclusions can be reached as to the true nature of this 
protein which, in its solubility relations, has little in common 
with most other globulins. 
These results, together with the fact that the coagulated 
lactalbumin as well as the albumin fraction after repeated pre- 
cipitation with magnesium sulfate in the uncoagulated state 
yielded only a trace of phosphorus, show that phosphatides are 
associated only with the lactoglobulin. 
Preliminary tests showed that the filtrate from the coagu- 
lated globulin contained protein, which, even after adding more 
sodium chloride or acetic acid, could not be caused to separate 
by longer heating. A liberal quantity of alcohol therefore was 
