form syphiloderm_)
consists of a more or less generalized, scattered eruption, of large
pea- or dime-sized, flat pustules. They dry rapidly to crusts. The bases
of the lesions are a deep-red or copper color. Two types of the eruption
are met with.

In one type--the superficial variety--the crust is flat, rounded or
ovalish, of a yellowish-brown or dark-brown color, and seated upon a
superficial erosion or ulcer. The lesions are usually numerous, and most
abundant on the back, shoulders and extremities. It appears, as a rule,
within the first year, and generally runs a benign course.

[Illustration: Fig. 55. Rupia. (_After Tilbury Fox._)]

In the other type--the deep variety--the crust is greenish or blackish,
is raised and more bulky, often conical and stratified, like an oyster
shell--_rupia_; beneath the crusts may be seen rounded or
irregular-shaped ulcers, having a greenish-yellow, puriform secretion.
It is usually a late and malignant manifestation.

#How would you differentiate the large flat-pustular syphiloderm from
ecthyma?#

The syphilitic lesions are more numerous, are scattered, are attended
with superficial or deep ulceration, and followed by more or less
scar-formation. Moreover, the history, and presence or absence of other
symptoms of syphilis have an important diagnostic value.

[Illustration: Fig. 56. Ulcerating Tubercular Syphiloderm.]

#Describe the bullous eruption of syphilis.#

The _bullous syphiloderm_, (of acquired syphilis) is a rare and usually
late eruption, appearing in the form of discrete, disseminated, rounded
or ovalish, pea- to walnut-sized, partially or fully distended, blebs.
The serous contents soon become cloudy and puriform. In some cases the
lesions are distinctly pustular from the beginning. The crust, which
soon forms, is of a yellowish-brown or dark green color, and may be
thick and stratified (_rupia_), as in the deep variety of the large
flat-pustular syphiloderm. The erosions or ulcers beneath the crusts
secrete a greenish-yellow fluid. It is a malignant type of eruption, and
is usually seen in broken-down subjects.

It is not an uncommon manifestation of hereditary syphilis (_q. v._) in
the newborn.

[Illustration: Fig. 57. Tubercular Syphiloderm.]

#How is the bullous syphiloderm to be differentiated from other
pemphigoid eruptions?#

By the gravity of the disease, the accompanying ulceration, the course
and history; and by other evidences, past or pre