The benzidine stain (Lepehne1 and Pickworth2) has provided a new method for morphologic study of the vascular pattern of the brain in health and disease. The normal vascular pattern of the brain has frequently been investigated by methods of injection, the outstanding work being Pfeifer's extensive monographs.3 The application of injection methods to pathologic material, however, has been limited. Pfeifer4 investigated by injection the vascular pathologic picture in tuberculosis of the monkey brain and Putnam5 that in lesions of multiple sclerosis in man. Aside from these isolated studies, the method has not found wide application. The reason for this may be found in the obvious drawbacks of injection methods when applied to pathologic material: (1) the uncertainty of securing adequate injection in postmortem material and (2) the inevitably artificial picture obtained in that the mass injected, being introduced at an arbitrary pressure, cannot show accurately