Cornea. Light micrograph of a section through a cornea, the transparent region on the outer surface of the eye. The front of the eye is at left. The corneal epithelium (dark pink) is supported by a basement membrane known as Bowman's membrane (solid blue line, top to bottom left). Beneath this lies the substantia propria (dispersed blue lines), the dense connective tissue that constitutes the bulk of the cornea. On the inner surface of the cornea is a layer of endothelial cells (pink, top to bottom right), supported by a basement membrane known as Descemet's membrane (left of endothelium). Trichrome blue stain. Magnification unknown.