Biopsies of the conjunctiva and cornea from a patient with benign mucous membrane pemphigus have been observed electron microscopically. The normally loosely connected conjunctival epithelial cells have become closely interconnected with markedly increased desmosomes, while the normally compact interdigitated corneal epithelium has become widely separated with conspicuously wide intercellular spaces in the basal zone. Goblet cells are absent. Keratin formation is not observed. The epidermalization of this entity may be different from common xerosis.