ply of the proposed flap may influence
its selection and the way in which it is fashioned; for example, a flap
cut from the side of the head to fill a defect in the cheek, having in
its margin of attachment or pedicle the superficial temporal artery, is
more likely to take than a flap cut with its base above.

Another modification is to raise the flap but leave it connected at both
ends like the piers of a bridge; this method is well suited to defects
of skin on the dorsum of the fingers, hand and forearm, the bridge of
skin is raised from the abdominal wall and the hand is passed beneath it
and securely fixed in position; after an interval of 14 to 21 days, when
the flap is assured of its blood supply, the piers of the bridge are
divided (Fig. 1). With undermining it is usually easy to bring the
edges of the gap in the abdominal wall together, even in children; the
skin flap on the dorsum of the hand appears rather thick and
prominent--almost like the pad of a boxing-glove--for some time, but
the restoration of function in the capacity to flex the fingers is
gratifying in the extreme.

[Illustration: FIG. 1.--Ulcer of back of Hand covered by flap of skin
raised from anterior abdominal wall. The lateral edges of the flap are
divided after the graft has adhered.]

The indirect element of this method of skin-grafting may be carried
still further by transferring the flap of skin first to one part of the
body and then, after it has taken, transferring it to a third part.
Gillies has especially developed this method in the remedying of
deformities of the face caused by gunshot wounds and by petrol burns in
air-men. A rectangular flap of skin is marked out in the neck and chest,
the lateral margins of the flap are raised sufficiently to enable them
to be brought together so as to form a tube of skin: after the
circulation has been restored, the lower end of the tube is detached and
is brought up to the lip or cheek, or eyelid, where it is wanted; when
this end has derived its new blood supply, the other end is detached
from the neck and brought up to where it is wanted. In this way, skin
from the chest may be brought up to form a new forehead and eyelids.

Grafts of _mucous membrane_ are used to cover defects in the lip, cheek,
and conjunctiva. The technique is similar to that employed in
skin-grafting; the sources of mucous membrane are limited and the
element of septic infection cannot always be excluded.

_Fat._--Adip