In a case of Routledge’s, with extensive recent exudate, the condition advanced from apparent health to extensive paralysis in three days, while in a case which the author obtained in slaughtering a tuberculous herd no special nervous symptoms had been noticed during life. Much therefore depends on the rapidity as well as the seat of development. The primary lesions in the brain are of the nature of miliary tubercles in the pia mater which becomes congested, rough, granular, and throws out a free serous secretion. Thus hydrocephalus is a usual concomitant of the affection. The disease is characterized by its slow advance in keeping with gradual increase of the tubercle and is thus distinguishable from the more acute congestions and inflammations. The earlier stages are usually marked by nervous irritability, hyperæsthesia, intolerance of light, closed eyelids, congested conjunctiva, grinding of the teeth and even spasms partial or general. The second stage shows somnolence, deepening into stupor or coma, or there may be going in a circle or other irregular movement. Squinting usually convergent, dilated pupils and congestion of the optic disc frequently occur. The sleep, stupor, paralysis or coma may set in early and is usually largely due to the amount of exudation and the rapidity of its effusion. TUMORS OF THE BRAIN. NEOPLASMS. Existence inferential with similar external tumors. Cholesterine tumors on plexus of lateral, third or fourth ventricle: pea to egg: in old; concentric layers with abundant exudate. Symptoms: slight, or excitability, dullness, vertiginous paroxysms with sudden congestions, as in encephalitis, sopor, stupor, paresis, coma. Melanoma: mainly meningeal; pea to walnut; with skin melanomata in gray or white horses. Cases. Pigmented sarcomata. Diagnosis, inferential. Psammoma: advanced cholesteatoma, melanoma, fibroma, etc.: osteid tumors. Nervous irritation, delirium, spasms, nervous disorder, and paroxysms. Myxoma: contains mucin: cells (in homogeneous matrix) round, spindle-shaped or stellate. Changes to fat (cholesterin). Œdematous connective tissue, neoplasm. Myxolipoma. Myxo-cystoid. Symptoms. Tumors in the brain are not marked by distinct pathognomonic symptoms, so that their presence is to be inferred as a probability rather than pronounced upon as a certainty. The most common forms in the horse are cholesterine (cholesteatoma), melanotic (melanoma), sandy, gritty (psammoma), and fibrous (fibroma). CHOLESTEATOMA.