to see the edema disappear. When no direct specific cause can be discovered
and the animal is debilitated, give general tonic. If, on the contrary, it
is in good flesh, give a purgative, followed by half an ounce of acetate of
potassium twice a day. External applications are useless.

Edema may be distinguished from erysipelas or anthrax by the absence of
pain and fever.

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 papillae, covered with a thickened
epidermis, the number of papillae 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