1. Branch of Surgical Neurology, and the Laboratory of Neuropathology and Neuroanatomical Sciences, National Institute of Neurological Diseases and Stroke, National Institutes of Health, Public Health Service, U. S. Department of Health, Education and Welfare, Bethesda, Maryland, 20014; Neurosurgical Service, Massachusetts General Hospital, Boston, Massachusetts
2. Branch of Surgical Neurology, and the Laboratory of Neuropathology and Neuroanatomical Sciences, National Institute of Neurological Diseases and Stroke, National Institutes of Health, Public Health Service, U. S. Department of Health, Education and Welfare, Bethesda, Maryland, 20014