_Symptoms._--Inflammation of the heart muscle is shown by inability to contract forcibly. This results in a rapid but weak, soft pulse and irregular heart sounds. The pulse may be quite irregular as a result of the irregular, tumultuous action of the heart. There is great general weakness, shortness of breath, and rapid respiratory movements. In some cases, where the muscle is very much softened and weakened, or, perhaps when an abscess forms in the wall of the heart, the course of the disease is very rapid and terminates suddenly from paralysis or rupture of the heart. _Alterations._--The heart muscle has a brownish or yellowish, boiled appearance, and is so brittle that it tears easily. There may be a spotted appearance of the muscle from the intense changes in structure in small areas. These small areas may be due to suppuration, in which case they have the characteristics of small abscesses. This last condition is seen in pyemia (blood poisoning). If the disease is of long duration, the fibrous tissue in the wall of the heart may increase to such an extent as to produce an unnatural hardness of the wall. _Treatment._--In this disease the nutrition and strength of the heart should be kept up as much as possible with good food, good care, and heart tonics and stimulants. The horse should be tempted to eat such foods as he will take; he should be kept in an airy box stall; his legs should be well rubbed as often as necessary to keep them warm and bandaged loosely with flannel bandages. Internally the horse may have strychnia, in 2-grain doses twice daily, whisky in 4-ounce doses every two to four hours, digitalis in the form of the tincture in doses of 1 dram every three to six hours. Artificial Carlsbad salts in heaping tablespoonful doses in the feed may be given three times daily for a couple of weeks. Rest is of the greatest importance and should be allowed for a few weeks after recovery seems to be complete. ENDOCARDITIS, OR INFLAMMATION OF THE LINING MEMBRANE OF THE HEART. Endocarditis frequently occurs as a complication of rheumatism, some of the specific or zymotic fevers, specific poisoning, etc. This is a more frequent disease among horses than is generally known, and often gives rise to symptoms which at first are obscure and unnoticed. In influenza we may find the heart becoming involved in the disease, in consequence of the morbid material conveyed through the heart in the blood stream. In view of the fact that many affections in even remote portions of the body may be traced directly to a primary endocardial disease, we shall feel justified in inviting special attention to this disease.