This gross and histopathologic study of the seminal vesicles and ejaculatory ducts constitutes one feature of a comprehensive and correlated study of these structures, carried out under the supervision of Dr. Joseph F. McCarthy, director of the Department of Urology at the New York Post-Graduate Hospital. To date, about eighty-four bladders have been subjected post mortem to careful serial microscopic examination of the region between the verumontanum and the interureteric ligament. The sections have been made transversely and sagittally, in such a manner as to include the prostate, ejaculatory ducts and seminal vesicle in their normal relationship to one another. These bladders have been selected from hundreds of necropsies, because of definite gross observations indicating acute, subacute and chronic inflammation of the entire region. An opportunity was thus afforded to study the verumontanum, ejaculatory ducts and seminal vesicles in specimens which presented frank inflammatory lesions of the posterior urethra and