e resulting from the breaking down of superficial syphilitic
gummata (Fig. 16). Fresh crops of nodules appear in the neighbourhood of
the ulcers, and in turn break down. While in the nodular stage the
affection is sometimes painful, but with the formation of the ulcer the
pain subsides.

The disease runs a chronic course, and may slowly extend over a wide
area in spite of the usual methods of treatment. After lasting for some
months, or even years, however, it may eventually undergo spontaneous
cure. The most satisfactory treatment is to excise the affected tissues
and fill the gap with skin-grafts.

[Illustration: FIG. 17.--Syphilitic Ulcers in region of Knee, showing
punched-out appearance and raised indurated edges.]

The _syphilitic ulcer_ is usually formed by the breaking down of a
cutaneous or subcutaneous gumma in the tertiary stage of syphilis. When
the gummatous tissue is first exposed by the destruction of the skin or
mucous membrane covering it, it appears as a tough greyish slough,
compared to "wash leather," which slowly separates and leaves a more or
less circular, deep, punched-out gap which shows a few feeble unhealthy
granulations and small sloughs on its floor. The edges are raised and
indurated; and the discharge is thick, glairy, and peculiarly offensive.
The parts around the ulcer are congested and of a dark brown colour.
There are usually several such ulcers together, and as they tend to heal
at one part while they spread at another, the affected area assumes a
sinuous or serpiginous outline. Syphilitic ulcers may be met with in any
part of the body, but are most frequent in the upper part of the leg
(Fig. 17), especially around the knee-joint in women, and over the ribs
and sternum. On healing, they usually leave a depressed and adherent
cicatrix.

The _scorbutic ulcer_ occurs in patients suffering from scurvy, and is
characterised by its prominent granulations, which show a marked
tendency to bleed, with the formation of clots, which dry and form a
spongy crust on the surface.

In _gouty_ patients small ulcers which are exceedingly irritable and
painful are liable to occur.

_Ulcers associated with Malignant Disease._--Cancer and sarcoma when
situated in the subcutaneous tissue may destroy the overlying skin so
that the substance of the tumour is exposed. The fungating masses thus
produced are sometimes spoken of as malignant ulcers, but as they are
essentially different in their nature fr