g an ordinary
crack or fissure, and its true nature is only revealed when the
secondary manifestations of syphilis appear.

_Mucous patches_ and _superficial ulcers_ are frequently met with on
the mucous surface of the lips and at the angles of the mouth during
the secondary stage of syphilis. In the inherited form of the disease
deep cracks and fissures form, and often leave characteristic scars
which radiate from the angles of the mouth.

Gummatous lesions occur on the lips, and are liable to be mistaken for
epithelioma.

_Tumours._--_Naevi_ are not uncommon on the lips. When confined to the
mucous surface they may be dissected out, but when they invade the
skin they are best treated by electrolysis.

_Lymphangioma._--The term _macrocheilia_ is applied to a congenital
hypertrophy of the lip (Fig. 241), which is probably of the nature of
a lymphangioma (Middeldorpf). One or both lips may be affected. The
lip is protruded, the mucous membrane everted, and, when the lower lip
is implicated, it becomes pendulous and is liable to ulcerate. The
substance of the lip is uniformly firm and rigid, so that it moves in
one piece, and sucking, mastication, and phonation are interfered
with.

[Illustration: FIG. 241.--Macrocheilia.

(From a photograph lent by Sir H. J. Stiles.)]

The _treatment_ consists in removing a wedge-shaped portion of the
swelling on the same lines as for "strumous lip," or in employing
electrolysis.

_Mucous cysts_ occur as small rounded tumours, projecting from the
inner surface of the lip. They are of a bluish colour, and contain a
glairy fluid. They are treated by removal of the cyst wall, together
with the overlying portion of mucous membrane.

#Epithelioma of the lip# is of the squamous-celled variety, and is met
with either as a fungating wart-like projection, or as an indurated
ulcer. It almost exclusively occurs on the lower lip of men over forty
years of age. The growth begins about midway between the middle line
and the angle of the mouth, either as a horny epidermal thickening, or
as a warty excrescence, which bleeds readily and soon ulcerates. The
affection is said to be especially common in those who smoke short
clay pipes, and it is a suggestive fact that, while epithelioma of the
lip is rare in women, the majority of those who do suffer are
smokers.

The ulceration spreads along the lip, chiefly towards the angle of the
mouth, and downwards towards the chin, and the substance of