The case to be described was deemed worthy of report because of the interesting development. It is not uncommon to find instances of Bowen's disease of the vulva, since cases of that disorder have been presented by Jessner,1Bloch,2Geiger,3Fuhs,4Rusch5and Arzt.6Rousset7gathered eighteen cases in which Bowen's disease affected the mucous membranes—seven in which it affected the glans and eleven in which it involved the vulva. In none of these cases was there any indication that syphilis had preceded Bowen's disease or played any part in its development. There still persists a great controversy in the literature as to whether Bowen's disease is a precancerosis or merely a stage in the development of a basal, squamous or mixed basal and squamous cell carcinoma. Grütz8and Gutman9first showed microscopically the change of a lesion of Bowen's disease