SYMPTOMS.—Feeble impulse of the heart, with louder sounds than are usually heard on applying the ear to the chest. The pulse is generally slow, feeble and intermittent. The veins in the neck may also be observed to pulsate. The animal is dull and fastidious in his appetite; dropsical swellings appear on the chest and belly; the legs become cold or œdematous. There is difficulty in breathing on the slightest exertion, and sometimes palpitation or fluttering of the heart. PATHOLOGY.—There are two forms of Atrophy, one in which there is a wasted and flabby appearance of the organ, whose parietes are so weak that when removed from the body it does not retain the rounded symmetry of a natural heart, but becomes a shapeless mass when thrown on the ground. This form of Atrophy was frequently met with during the prevalence of the Cattle Plague, and it has been observed in connection with some forms of Influenza. The second form of Atrophy is termed Fatty Degeneration of the heart. Of this there are two varieties. In one the fat grows on the surface of the organ, encroaching on and insinuating itself between the muscular fibres, impoverishing them, and ultimately causing them to waste; the result is that the muscular walls become thin. In the other variety, fat in a molecular form takes the place of the muscular element, and ultimately fills the sheaths, which previously contained muscular fibre. Dilatation of the Heart DEFINITION.—Enlargement of one or more of the cavities of the heart. CAUSES.—Some defect in the valvular apparatus, allowing the blood to regurgitate and to distend the cavity, which, by pressure on the walls, causes absorption and attenuation; loss of power in the nervous system; fevers of a sthenic or typhoid character, which weaken the muscular fibres. SYMPTOMS.—The action of the heart is feeble and tremulous; the pulse small, soft and weak; the least exertion brings on Dyspnœa; there are languor, giddiness, or “Megrims”; the horse is “off his food”; the ears and legs are cold; and ultimately there is œdema of the legs, belly and chest. PATHOLOGY.—Dilatation may exist either with Hypertrophy or with Atrophy of the walls of the heart, and in the latter case is most probably an effect of the emaciated state of the muscular substance of the heart, which allows the blood to accumulate, and to distend one or more of the auricles or ventricles. TREATMENT.—Dilatation and atrophy of the heart admit of very little help in the majority of cases, moderate work and occasional or daily use of A.A., will be proper, and do something towards improving the condition and prolonging the usefulness of the animal. Palpitation DEFINITION.—An abnormal increase in the action of the heart.