=Prognosis.=—Under medical treatment it is unfavorable; may last twenty years. Slight opacity of the cornea may develop. =Treatment.=—The eyes should be protected with dark glasses. Cold compresses give some relief. Boric acid is good as a wash. Yellow oxide of mercury ointment may be of service as an antiseptic and alternative. If nasal disease exists, it, of course, should be treated according to indications. Fundamentally the lesions in the spine in the cervical and upper dorsal regions should be specifically corrected. When enough cases of vernal catarrh have been observed and treated osteopathically much light and benefit will be brought to bear upon this obscure and intractable disease of the conjunctiva. Diseases of the Cornea Anatomy The cornea with the sclera forms the outer coat or tunic of the eye ball. The cornea is in front and forms one-sixth of the envelope. It is a segment of a smaller globe than that of the sclera. It is about 12 mm. horizontally and 11 mm. in the vertical diameter. Its thickest part is at its junction with the sclera where it is about 1 mm. This junction is called the limbus. The cornea is inserted into and rests on the sclera like a watch crystal. The fibers of the cornea pass continuously into the sclera, however. The normal cornea is transparent. Most morbid changes of the cornea cause a diminution in this transparency. In old age a narrow gray line near the corneal margin makes its appearance. This is known as the =arcus senilis=. There is a little strip of perfectly clear cornea between the arcus senilis and the limbus. The cornea has five layers. These layers should be noted with care, as in wounds of the eye, foreign bodies in the cornea and ulcerations, the results depend much upon which layers are affected. 1. The =anterior epithelium= consists of pavement cells of several layers. This layer of the cornea may be damaged or scratched off in large patches and still it will heal readily leaving no trace of the injury. 2. The =anterior elastic lamina= or =Bowman’s membrane= is very thin and homogeneous; it is just beneath the epithelial layer and forms a resisting sheath to prevent damage to the next layer. 3. The =stroma= or =substantia propria=. This layer composes about nine-tenths of the cornea. It is composed of minute connective tissue fibers between which lie some stroma cells or corneal corpuscles. Some of these cells are fixed while others are motile. The motile ones are the white blood-corpuscles which move about in the lymph passages of the stroma. They increase in any irritation of the cornea. 4. =Descemet’s membrane.= This is a tough homogeneous hyaloid membrane back of the stroma. When the stroma is diseased and breaks down Descemet’s membrane may be sufficient to prevent a puncture of the cornea. 5. The =Endothelial layer= is a single layer of flattened cells which coat the posterior surface of Descemet’s membrane.