Corneal tissue, removed during penetrating keratoplasty from two patients who had received severe chemical burns, was examined using light and transmission electron microscopy. In both corneas, there was a conjunctival overgrowth and blood and lymphatic vessels were present below the epithelium. The lymphatic vessels had thin walls, incomplete basement membranes, abluminal endothelial projections, anchoring filaments, and an absence of pericytes. The significance of corneal lymphatic vessels in relation to graft rejection is discussed.