The recognition of a new growth in the cranial cavity may be either extremely difficult or exceedingly easy. The diagnosis, however, should always be made with some reserve, as the symptoms to which the condition gives rise may be reproduced by other disorders. Even when it has been decided that a tumor is present, its situation and its pathologic nature may be practically indeterminable. Finally, intracranial neoplasm has been found after death in a number of cases in which there were no suggestive symptoms during life. The difficulties in diagnosis are thus considerable and obvious, and they must seriously embarrass any decision with regard to treatment, and especially surgical intervention. In an interesting discussion on this subject, Reynolds (British Med. Jour., Feb. 11, 1899, p. 333) names the following disorders as capable of simulating brain tumors: chlorosis, uremia, chronic lead poisoning, hysteria, so-called reflex epilepsy, syphilis, meningitis, polioencephalitis and a