During the five weeks from April 1 to May 5, 1939, inclusive, we had occasion to make a diagnosis of melanoma of the central nervous system in four cases. The rapid succession of these four tragic experiences prompted us to carry out the present study. A survey of the literature on melanoma reveals an almost endless list of contributions covering various phases of the subject. In this presentation we are not concerned with the histologic structure of melanoma but wish to stress the importance of melanoma from the neurologic standpoint. We are employing the terms "melanoma," "melanocarcinoma," "melanosarcoma" and "melano-epithelioma" synonymously. That melanomas are a serious menace to life needs no comment. The frequency of their occurrence remains somewhat uncertain. Adair1reported that 400 cases were observed at the Memorial Hospital in Chicago during an eighteen year period. In 41,984 surgical specimens examined by the department of pathology at