This disease is an involvement of the cornea with an eczematous process similar to phlyctenular conjunctivitis. There is more likely to be ciliary injection and iritis, in which case atropine should be used. The treatment is the same otherwise as for phlyctenular conjunctivitis. Parenchymatous or Interstitial Keratitis This is shown by a diffuse inflammatory infiltration of the substantia propria of the cornea. Part or whole of the cornea of one or both eyes may be involved. Very fine blood vessels may invade the deep structures of the cornea. =Cause.=—Syphilis, tuberculosis, rheumatism, diabetes and rachitis are systemic diseases found back of this trouble. =Symptoms.=—Irritation, lachrymation, photophobia with ciliary injection are the chief symptoms. =Treatment= must be local and constitutional. Locally atropine should be used. Dark glasses should be worn or the patient must be kept in a dark room. Treatment to the trigeminal nerve and tissues of the orbit should be given. Constitutional treatment should be spinal with the idea of arousing all the forces of the body to greater activity. Careful dieting should be followed according to indications. The infiltration and blood vessels will ultimately disappear. Sometimes enough may remain to cloud the vision. Diseases of the Iris and Ciliary Body The iris and ciliary body have the same blood and nerve supply. That is, they are supplied by the same set of vessels and nerves. For this reason it is practically impossible to have an iritis absolutely independent of a cyclitis or some inflammation of the ciliary body. If the iris is the primary seat of the trouble there are certain symptoms that may indicate such a state. However, when we are treating the iris or diagnosing conditions of the iris we must remember that the ciliary body is very likely more or less involved and may be the primary seat of the trouble. In =iritis= there are some symptoms which are caused from the hyperemic condition of the eye, such as a slight change in color. The pupil becomes rather inactive, there is some ciliary injection with photophobia, lacrymation and pain. In case of an exudate in the iris there may be thickening, and the exudate in the anterior chamber of the eye will form a =hypopyon=. Sometimes the small vessels will break and there will be a little bleeding which will be mixed with the debris in the bottom of the anterior chamber. This is known as hyphemia. There are likely to be adhesions between the iris and the anterior capsule of the lens known as posterior =synechia=. The pupil is more or less irregular. If atropine is dropped into the eye to dilate the pupil, parts of the edge of the pupil will be adhered while the other parts dilate making it very irregular.