all cases of haemorrhage, caused by wounds of the
vessels of the upper limb, we should, if at all practicable, endeavour
to stop the flow of blood from the divided vessels in the wound itself,
by ligature or otherwise; and both ends of the divided vessel require to
be tied. Whenever this may be done, we need not trouble ourselves
concerning the anomaly in vascular distribution.

The superficial palmar arch, F, Plate 17, lies beneath the dense palmar
fascia; and whenever matter happens to be pent up by this fascia, and it
is necessary that an opening be made for its exit, the incision should
be conducted at a distance from the locality of the vessel. When matter
forms beneath the palmar fascia, it is liable, owing to the unyielding
nature of this fibrous structure, to burrow upwards into the forearm,
beneath the annular ligament D, Plates 17 and 18. All deep incisions
made in the median line of the forepart of the wrist are liable to wound
the median nerve B, Plate 17. When the thumb, together with its
metacarpal bone, is being amputated, the radial artery E, Plate 19,
which winds round near the head of that bone, may be wounded. It is
possible, by careful dissection, to perform this operation without
dividing the radial vessel.

DESCRIPTION OF PLATES 17, 18, & 19.

PLATE 17.

A. Radial artery.

B. Median nerve; b b b b, its branches to the thumb and fingers.

C. Ulnar artery, forming F, the superficial palmar arch.

D. Ulnar nerve; E e e, its continuation branching to the little and ring
fingers, &c.

G. Pisiform bone.

H. Abductor muscle of the little finger.

I. Tendon of flexor carpi radialis muscle.

K. Opponens pollicis muscle.

L. Flexor brevis muscle of the little finger.

M. Flexor brevis pollicis muscle.

N. Abductor pollicis muscle.

OOOO. Lumbricales muscles.

P P P P. Tendons of the flexor digitorum sublimis muscle.

Q. Tendon of the flexor longus pollicis muscle.

R. Tendon of extensor metacarpi pollicis.

S. Tendons of extensor digitorum sublimis; P P P, their digital
prolongations.

T. Tendon of flexor carpi ulnaris.

U. Union of the digital arteries at the tip of the finger.

[Illustration: Right hand, showing blood vessels, muscles and other
internal organs.]
Plate 17

PLATE 18.

A. Radial artery.

B. Tendons of the extensors of the thumb.

C. Tendon of extensor carpi radialis.

D. Annular ligament.

E. Deep palmar arch, formed by radial artery giv