The surface tissues, namely, the skin and the mucous membranes, constitute the principal sites of the allergic reaction. The symptoms vary according to whether the allergen is inhaled, ingested or brought into immediate contact with the tissues. The eye with its coverings of skin and mucous membrane and richly endowed with an abundant blood and nerve supply is often the site of such a reaction. The present study of the etiology of corneal ulcers offers further evidence of a growing interest in the allergic aspect of cases seen by the practicing ophthalmologist. In a recent editorial in one of the journals on ophthalmology1 the statement was made, "It is not to be denied that many inflammations of the conjunctiva are manifestations of allergy and will yield most readily to treatment based upon the recognition of this fact." Lehrfeld,2 in reporting his observations on eighty-seven cases of