Abstract
From the basis of an examination of the literature, and on a personal exerience of the surgical treatment of 100 cases of calculus disease, the suggestion is made that 2 distinct mechanisms of calculogenesis should be recognised. Calculi of metabolic origin should be considered as having an entirely distinct aetiological mechanism. Phosphatic calculi are apparently determined by the existence of urinary tract infection. Partial nephrectomy does not seem indicated for either type of disease.