Nuclear staining qualities, and cell morphology depart from normal when epithelial cells are infected by herpes virus hominis and herpes varicella-zoster (1). The cytopathic changes produced by both viruses are similar and constant enough to be considered characteristic of the infection. Since the skin vesicles are readily accessible for examination, it is easy to scrape infected cells from the floor of the exposed blister and establish the diagnosis. The simplest and most common method would be by light microscopy utilizing conventional staining. When the circumstances warrant it and the facilities are available, the virus itself can be demonstrated by electron microscopy with material obtained in the same fashion. This paper deals with two cases in which the initial diagnosis of the disease was made by cytologic examination and the presence of virus subsequently verified by electron microscopy.