In another paper1 I have reviewed the various theories which have been proposed regarding the origin of Bence Jones protein. In the paper preceding this one I have described experiments which, conducted under the direction of Prof. W. J. Gies, were planned to determine whether osseo-albumoid, a constituent of bone, is a precursor of Bence Jones protein. That inquiry warranted the conclusion that the Bence Jones protein may be formed from osseo-albumoid by the action of enzymes in diseased bone.
The chemical nature of Bence Jones protein has been thoroughly studied, but very little is known regarding the mode of formation of this important substance. Weber and Ledgingham2 have suggested that the cytoplasmic residue of karyolyzed plasma cells is the source of Bence Jones protein. If this view is correct, the endogenous purins of the urine should be supernormal in amount owing to increased nuclear destruction. Preparations were