The following layers of the epithelium are labelled:

• Basal cell layer (stratum basale) (A) in which the epithelial cells divide. They renew themselves and give rise to the epithelial cells of the stratum spinosum above.
• Polyhedral cell layer (stratum spinosum) (B). These cells, which show pale boundaries, transform into the cells of the next layer above.
• Granular cell layer (stratum granulosum) (C) composed of squamous cells containing an increasing number of basophilic keratohyalin granules.
• Cornified layer (stratum corneum) (D) formed of epithelial cell residues derived from the sudden transformation of the cells of the stratum granulosum. This layer is composed of soft keratin.

All the nucleated epithelial cells of this epithelium may be called keratinocytes.

Stain: H–­­E
Magnification: ×900