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THE HOG.

the animal betrays symptoms of thirst, there is dulness, loss of appetite, and grinding of the teeth. As the malady progresses the patient becomes inert, deaf, insensible to blows, lies down constantly, and totters and falls if compelled to rise; the flanks heave, the mouth is hot and full of slaver, the tongue red and inflamed, the lower jaw convulsed, and the conjunctiva injected; the animal utters plaintive moans, and if not speedily relieved dies of suffocation, from the effects of the pressure of the tumor upon the air-passages.

D'Arboval attributes this disease to the irritation caused in some of the cutical tissues by the abnormal growth of the tuft of hair, which, uniting with some internal sympathetic irritation induced by heating food, damp litter, hot ill-ventilated styes, or such like prejudicial influences, acts locally and determines this disease of the glands. Other French writers believe it to be epizoötic and to arise from certain miasmatic influences.

Tonics, acidulated drinks, warmth, cleanliness, strict attention to diet, and the application of actual cautery to the root of the evil—the tuft of hair is the treatment prescribed.

THE CHEST OR THORAX.

In the human being this constitutes the superior, and in quadrupeds the anterior portion of the body; it is separated from the abdomen by the diaphragm. This latter is of a musculo-membranous nature, and is the main agent in respiration; in its quiescent state it presents its convex surface towards the thorax, and its concavity towards the abdomen. The anterior convexity abuts upon the lungs, the posterior concavity is occupied by a portion of the abdominal viscera. The diaphragm of the pig resembles that of the ox and sheep.

The chest is divided into two cavities by a membrane termed the mediastinum, which evidently consists of a duplicate of the pleura or lining membrane of the thorax. The pleura is a serous membrane possessed of little or no sensibility, and acted upon by but few nerves. It it smooth and polished; covers the bony wall of the thorax from the spine to the sternum, and from the first rib to the diaphragm, and dilating and forming a kind of bag which spreads over and contains the whole of the lung.

The lungs form two distinct bodies, the right being somewhat larger than the left one; they are separated from each other by that folding over of the pleura termed the mediastinum, and hence may be said to be inclosed in separate bags, or to have distinct pleuras. Each lung is subdivided. The right one consists of three unequal lobes, the smallest of which is again subdivided into numerous lobules, differing in number in different swine. The left lung consists of two lobes, and the scissure between these is not very deep.