The cornea is continuous with the sclera, but in contrast to the sclera, it is transparent and lacks blood vessels.

Examine the images below and the cornea in this slide , and identify the five layers of the cornea: the surface epithelium (SE, a stratified squamous epithelium), anterior limiting membrane (BM, Bowman's membrane), the thick stroma (S) or substantia propria, posterior limiting membrane (DM, Descemet's membrane), and the corneal endothelium (E) lining the posterior surface.

Clinical note: Corneal surgery to improve vision by changing the shape of the eye is now common. Making a radial arrangement of incisions into the stratified surface epithelium and stroma with a computer-guided scalpel, a process called radial keratotomy (RK), changes the shape of the cornea as the incisions heal. A newer procedure called laser in situ keratomileusis (LASIK) involves making a flap in the center of and partially through the cornea, using a computer-controlled beam of UV light to sculpt the underlying stroma, and repositioning the flap.

Last, let's look at the eyelid.