The periods between these acute attacks of ophthalmia may vary from a few weeks to several months. Severe work, debility and the character of the ration influence their frequency. It is not uncommon for animals that have been given a rest to suffer from a second attack on being put to work. The attendant may observe a hazy or whitish condition of the margin of the cornea. The upper lid may show an abrupt bend of its margin and a deep wrinkle. The color of the iris appears to have lost its lustre, and the aqueous humor and lens may be cloudy. After a variable number of attacks glaucoma or cataract develops. _The history_ of the case will enable the attendant to recognize this form of ophthalmia. _Treatment_ is unsatisfactory. Preventive measures consist in avoiding conditions favorable to the production of the disease. This should be practised so far as possible. At the time the attack occurs, the animal should be given a cathartic. One pound of Glauber's salts in a drench is to be preferred. Rest in a darkened stall is indicated. An eye lotion containing three grains of silver nitrate in one ounce of distilled water should be applied to the eye three times daily. A water solution of atropine or eserine should be used for the purpose of relieving the symptoms of iritis or glaucoma. A very light diet should be fed. INFECTIOUS OPHTHALMIA OF RUMINANTS.--This occurs as an acute inflammation of the eyelids and cornea. The disease is highly infectious, affecting all of the susceptible animals in the herd. It commonly occurs during the late summer and fall. _The symptoms appear_ suddenly. The animal is feverish, the eyes closed and the cheeks are wet with tears. The cornea becomes clouded, white and opaque. In severe cases, the blood-vessels around the margin of the cornea become prominent, and ulcers form on its surface. The animal's appetite is impaired or lost. There is loss of flesh and temporary blindness. The blindness in one or both eyes may persist for a period of from two weeks to several months. Permanent blindness is comparatively rare. _The preventive treatment_ consists in practising the necessary precautions against the introduction of the disease into the herd, and in carefully quarantining the first cases of the disease that appear. The affected animal should be given a darkened stall, and fed a very light ration until the acute inflammation has subsided. From one to one and one-half pounds of Glauber's salts should be given. The _local treatment_ consists in the application of antiseptic lotions or powders to the eye. Equal parts of boric acid and calomel, dusted into the eye twice daily with a powder blower, is a very effective treatment. QUESTIONS 1. Name the different structures that form the shell of the eye; name and describe the different media of the eye. 2. Give the general method of examining the eyes of horses. 3. What is conjunctivitis? Give causes and treatment. 4. What is "moonblindness"? Give the symptoms.