“…T HE strong fluorescence that is seen in the nuclei of the cells of liver, kidneys, adrenals, and connective tissue after injection of 2-hydroxystilbamidine has already been described. 3 T h e presence of large amounts of 2-hydroxystilbamidine in different organs can be demonstrated not only by these photographic methods but also by chemical analysis. After stilbamidine injections, the fluorescence of cells and nuclei when examined with the fluorescent microscope is much less intense.…”