odent ulcer_), begins, usually on
the face, as a minute, firm, reddish or yellowish tubercle, as an
aggregation of such, as a warty excrescence, or as a localized
degenerative seborrh[oe]ic patch. The latter lesion (known also as
keratosis senilis, old-age atrophic patches), consisting of a yellowish
or yellowish-brown greasy or hardened scurfy spot or patch is quite
frequently the starting-point of epithelial growths. Sooner or later,
commonly after months or several years, the surface becomes slightly
excoriated, and an insignificant, yellowish or brownish crust is formed.
The excoriation gradually develops into superficial ulceration, and the
diseased area becomes slowly larger and larger. New lesions may
continue, from time to time, to appear about the edges and go through
the same changes.

[Illustration: Fig. 64. Epithelioma. (_After D. Lewis._)]

The ulcer has usually an uneven surface, secretes a thin, scanty, viscid
fluid, which dries to a firm, adherent crust. It is usually defined
against the healthy skin by a slightly elevated, hard, roll-like,
waxy-looking border. In rare instances there is a disposition, at
points, to spontaneous involution and scar formation; as a rule,
however, the ulcerative action slowly progresses.

The general health is unimpaired, the neighboring lymphatic glands are
not involved, and the local condition, beyond the disfigurement, gives
rise to little trouble, unless, as occasionally happens, it passes into
the more malignant, deep-seated variety.

#Describe the clinical appearances and course of the deep-seated variety
of epithelioma.#

The deep-seated variety starts from the superficial form, or it begins
as a tubercle or nodule in the skin. When typically developed, a
reddish, shining tubercle or nodule, or area of infiltration, forms in
the skin or subcutaneous tissue. In the course of weeks or months
superficial or deep-seated ulceration takes place; the ulcer having
hardened, and, as a rule, everted edges. The surface is reddish and
granular, and secretes an ichorous discharge. The infiltration spreads,
the ulcer enlarges both peripherally and in depth--muscle, cartilage and
bone often becoming invaded. The neighboring lymphatic gland may become
implicated, pains of a burning or neuralgic type are experienced, and
from septicaemia, marasmus, or involvement of vital parts, death
eventually ensues.

#Describe the clinical appearances and course of the papillomatous
v