Abstract
A comparison of the livetin of egg yolk and serum globulin of the common fowl using (a) anaphylactic and (b) precipitin reactions, indicates that the two proteins are very closely related, if not identical. The complement fixation test does not give the same result but indicates a difference between the two proteins. The complement fixation test also shows differences between serum euglobulin and serum pseudoglobulin when these proteins, prepared with considerable care, cannot be distinguished either by anaphylactic or precipitin tests.