cially
such as implicate the sub-aponeurotic area, or the pericranium. In the
integument, a small localised abscess, attended with pain and oedema
of surrounding parts, may form. Pus forming under the aponeurosis is
liable to spread widely, pointing above the eyebrow, in the occipital
region, or in the line of the zygoma. Suppuration under the
pericranium tends to be limited by the inter-sutural attachments of
the membrane. Necrosis of the outer table, or even of the whole
thickness of the skull, may follow, although it is by no means
uncommon for large denuded areas of bone to retain their vitality.

The onset of infection is indicated by restlessness, throbbing pain
and heat in the wound, a feeling of chilliness or the occurrence of a
rigor, and tension of the stitches from oedema of the surrounding
tissues. The oedema often extends to the eyelids and face; a puffiness
of the eyelids, indeed, is not infrequently the first evidence of the
occurrence of infection in the wound.

_Treatment._--When suppuration ensues, the stitches should be removed,
the wound opened up and purified with eusol, and packed. A dressing of
ichthyol and glycerine should be employed for a few days.

_Erysipelas of the scalp_ may originate even in wounds so trivial as
to be almost invisible, or from suppurative processes in the region of
the frontal sinuses or nasal fossae. It tends to be limited by the
attachments of deep fasciae, and seldom spreads to the cheek or neck.
Symptoms of cerebral complications, in the form of delirium or coma,
and of meningitis may supervene. Cellulitis beneath the aponeurosis
from mixed infection is a dangerous complication.

DISEASES OF THE SCALP

#Infective Conditions.#--It is not uncommon for _localised abscesses_
to occur in the subcutaneous cellular tissue in delicate children, and
such collections are not infrequently associated with pediculi,
impetigo, or chronic dermatitis. They develop slowly and painlessly,
and are only covered by a thin, bluish pellicle of skin. It is not
improbable that they result from a mixed infection by pyogenic and
tuberculous organisms. As a rule they heal quickly after incision and
drainage, but when they are allowed to burst, tedious superficial
ulcers may form. Localised abscesses may also form in connection with
disease of the cranial bones. _Suppuration_ following upon injuries
has already been referred to.

_Boils and carbuncles_ are not common on the hairy part of