WHEN A conventional contact lens is worn, the subject notes a haze or mistiness in his vision (Sattler's veil1), which can be shown to be due to corneal turbidity. Evidence has been produced indicating that contact lenses interfere with the normal water-removing function of the cornea,2 which, being extraordinarily hydrophilic, tends constantly to imbibe water.3 This water is continuously being removed, and recent experiments suggest that this is done, in part at least, by metabolic activity of corneal elements. Should this process fail, the cornea thickens4 and becomes hazy.5 It appears unlikely that changes caused by contact lenses could occur without morphologic modifications. Corneal metabolism is based essentially on carbohydrates, and the epithelium, which normally contains much glycogen, is responsible for the major part of the total metabolic activity of the cornea.6 It was thought that a histologic study of the cornea of animal