This electron micrograph shows the basal lamina as a thin gray moustache following parallel along the basal membrane of epithelial cells from human corneal epithelium. In this tissue, the basal lamina, which is secreted by the epithelial cells, is at the interface of the epithelial layer and Bowman's layer, which is composed of condensed collagen. Image by Toichiro Kuwabara, Figure 22 from Chapter 1 (The Cell Surface) of 'The Cell, 2nd Ed.' by Don W. Fawcett M.D. A PDF copy of the accompanying chapter is available on the ASCB's BioEDUCATE website.