This animal study of corneal surface injury using acid, alkali n-heptanol, iodine, keratectomy, or scraping, despite morphologic differences from the human, simulated the human response to these forms of trauma. The rabbit and monkey thus remain useful models for the study of the effects of chemical and physical injury on the corneal surface. Although abnormalities in the basement membrane complex seem to play an important role in corneal epithelial adhesion problems, the presence of a poor substratum on which adhesion complexes must in turn rely for their stromal attachment is also an important factor.