The two cases given herewith present true prostatic stones. The etiology of this type of stone, according to Young and Thompson1corpora amylacea, is as follows: The stones, having attained the size of their enclosing follicles, act as foreign bodies, and in consequence of the general law that all mucoid membranes, when sufficiently irritated, throw out a deposit of calcium phosphate and carbonate, ultimately form calculi. The amount of earthy matter varies from 45 per cent. in the concretion to 85 per cent. in the calculus. The number of stones is large as a rule, although one of my patients had only one, buried deep in the gland. REPORT OF CASES Case 1. —History. —A white man, unmarried, aged 25, whom I saw, April 21, 1919, reported a family history of no importance, and a good past history except that he had had a severe case of typhoid fever