DERMOID AND SEBACEOUS CYSTS (WENS).
A dermoid cyst is formed by an involution of the skin with a growth of hair on the inner wall of the sac. It may become embedded deeply in the subcutaneous tissues or may just penetrate the thickness of the skin, where it is movable and painless. They are generally found within the ear or at its base, although they may form on any part of the body. Usually they have a small opening, from which a thick, cheesy matter can be squeezed out. The rational treatment is to dissect them out.
Sebaceous cysts appear not unlike the former. They are formed by a dilatation of the hair follicle and sebaceous duct within the skin, and contain a gray or yellowish sebaceous mass. The tumor may attain the size of a cherry stone or a walnut. Generally they are round, movable, and painless, soft or doughy in consistency, and covered with skin and hair. They develop slowly. The best treatment is to dissect out the sac with contents entire.
VERRUCA (WARTS).
Cattle are affected with two varieties of warts. One, the verruca vulgaris, is composed of a cluster of enlarged papillæ, covered with a thickened epidermis, the number of papillæ determining the breadth and their length its height. They are generally circular in figure, slightly roughened on the surface, and spring from the skin by a broad base. Occasionally large numbers of very thin, long, pedunculated warts grow from the skin of the ear, lips, about the eyes, and vulva. Another variety, the verruca acuminata, sometimes erroneously denominated epithelial cancers, are irregularly shaped elevations, tufted or club shaped, occasionally existing as thick, short, fleshy excrescences, giving the growth the appearance of granulation tissue. Their color is red or purplish, and oftentimes by friction they become raw and bleeding, emitting then a very offensive odor. They usually grow in clusters and their development is rapid.
Causes.—An abnormal nutrition of the skin, determined by increased energy of growth operating upon a healthy skin; at other times, upon a weak or impoverished skin.
Treatment.—When they are small and pedunculated, they may be snipped off with shears and the stump touched with nitrate of silver. When they are broad and flattened, they may be dissected out and the wound cauterized if necessary. If they are large and very vascular, they may be ligated, one by one, by taking a strong cord and tying it as firmly around the base as possible. They will then shrivel, die, and drop off. If there is a tendency to grow again, apply a red-hot iron or nitric acid with a glass rod. Very often warts quickly disappear if they are kept soft by daily applications of sweet or olive oil.
KELIS.
Kelis is an irregularly shaped flat tumor of the skin, resulting from hypertrophy—increased growth of the fibrous tissue of the corium, producing absorption of the papillary layer.