Thickened cellular envelope of the horny cells in cow snout epidermis.

The cow snout epidermis consists of two different parts. The one has the granular cell layers, and the other not. Electron-microscopically, the generation of the lamellated granules and the thickened cellular envelope of a horny cell were noted in both regions. In the horny cell layer the remnant of the lamellated granules were observed locating in the intercellular space, that is, outside of the thickened cellular envelope. The thickened cellular envelope was generated by the precipitation of electron dense material along the inner leaflet of the plasma membrane, but neither by the attachment of small keratohyalin granules to the plasma membrane nor by the coating of the plasma membrane with the content of lamellated granules.