A MODIFICATION AND EXTENSION OF THE McREYNOLDS' OPERATION FOR PTERYGIUM*.

1. The penetration of sodium sulphacetaamide into the ocular tissues has been studied, both in living'rabbits and in isolated ocular tissues. 2. Application of the drug with a wetting agent, Duponal ME dry, increases the penetration of sodium sulphacetamide into and through the cornea. 3., Removal of the corneal epithelium causes a great increase in the penetration of the sulphonamide into antd through the cornea, i.e., the epithelium acts as a barrier to the passage of the drug. 4. The wetting agent does not increase the passage of the drug' into the denuded cornea (i.e., the cornea with the epithelium removed). It may be concluded that the wetting agent acts by overcoming the epithelial barrier.' 5. The, results suggest that addition of a wetting agent to sodium sulphacetamide would be of most value iih infections of the cornea and iris.