_Symptoms._ In pure atrophy these are the opposite of those seen in hypertrophy. The beats of the heart are weak or inappreciable to the hand placed on the side of the chest behind the left elbow. The sounds of the heart are loud and clear, their intensity being proportionate to the thinning of the walls and the dilatation of the chambers. Percussion so far as it can be made effectual, which is chiefly in dogs, shows a diminished area of dulness. The pulse is slow, weak, or indistinct, compressible, becoming accelerated, unequal, irregular, and intermittent when the patient is excited. Palpitation is frequent, breathing is difficult or easily embarrassed and there is a tendency to dropsy of the limbs and dependent parts. These symptoms are usually associated with considerable prostration and depression. These are often complicated by symptoms of valvular disease or dilatation. Atrophy progresses slowly and rarely causes death in the earlier stages. In its advanced stages when dropsy has supervened little can be done even in its mitigation. In the earliest stages only can good be done by employing measures calculated to remove its causes and thus put a stop to its progress. DILATATION OF THE HEART. Result of obstruction to circulation. In right ventricle usually. In auricle from narrow auriculo-ventricular opening. Pure dilatation from sudden extreme blood pressure as in inflammations of the lungs. In fat cattle from fatty obstructions around the heart and great vessels. Weakness of cardiac muscles in fatty degeneration, fevers, debility, etc. Symptoms, dyspnœa under slight exertion, unsteady walk, cold, dropsical limbs, venous pulse, pulse small, weak, irregular, intermittent, with palpitations. Treatment, in early stages arrest the causes, arsenic, digitalis, fatten for butcher.