1. Purchased from American Cystoscope Makers, Inc., New York, N.Y.
2. Cooper, J.A.D. Unpublished data.
3. Bulkley, G.J., Cooper, J.A.D., O’Conor, V.J.: To be published.
4. Flocks, R.H.: Personal communication.
5. The effect of particle size on blood clearance and tissue distribution of radioactive gold colloids;Zilversmit;J. Lab. & Clin. Med.,1952