A sporadic case of tuberous sclerosis in a stillborn infant is reported. The death at the 31st week of gestation was presumably due to the development of enormous rhabdomyomas of the heart. The typical cerebral lesions were fully developed as in patients decreased later in life. The atypical cells found in the cortical tubers demonstrated ultractructural features of reactive astrocytes. Moreover, they showed innumerable microvillilike projections on their surface and junctional complexes, mostly of the zonula adharens type, reminescent of ependymocytes. The significance of such glio-epithelial cellular features is discussed.