d, the clavicle follows it, and the
subclavian artery will be more exposed and more easily reached than if
the shoulder be elevated, as this latter movement raises the clavicle
over the locality of the vessel. Dupuytren alludes practically to the
different depths of the subclavian artery in subjects with short necks
and high shoulders, and those with long necks and pendent shoulders.
When the clavicle is depressed to the fullest extent, if then the
sterno-cleido-mastoid and scalenus muscles be relaxed by inclining the
head and neck towards the artery, I believe it may be possible to arrest
the flow of blood through the artery by compressing it against the first
rib, and this position will also facilitate the operation of ligaturing
the vessel.

The subclavian vein, W, Plate 5, is removed to some distance from the
artery, Q, Plate 5. The width of the scalenus muscle, X, separates the
vein from the artery. An instance is recorded by Blandin in which the
vein passed in company with the artery under the scalenus muscle.

DESCRIPTION OF PLATES 5 & 6.

PLATE 5.

A. Innominate artery at its point of bifurcation.

B. Subclavian artery crossed by the vagus nerve.

C. Common carotid artery with the vagus nerve at its outer side, and
the descendens noni nerve lying on it.

D. External carotid artery.

E. Internal carotid artery with the descendens noni nerve lying on it.

F. Lingual artery passing under the fibres of the hyo-glossus muscle.

G. Tortuous facial artery.

H. Temporo-maxillary artery.

I. Occipital artery crossing the internal carotid artery and jugular
vein.

K. Internal jugular vein crossed by some branches of the cervical
plexus, which join the descendens noni nerve.

L. Spinal accessory nerve, which pierces the sterno-mastoid muscle, to
be distributed to it and the trapezius.

M. Cervical plexus of nerves giving off the phrenic nerve to descend
the neck on the outer side of the internal jugular vein and over the
scalenus muscle.

N. Vagus nerve between the carotid artery and internal jugular vein.

O. Ninth or hypoglossal nerve distributed to the muscles of the tongue.

P P. Branches of the brachial plexus of nerves.

Q. Subclavian artery in connexion with the brachial plexus of nerves.

R R. Post scapular artery passing through the brachial plexus.

S. Transversalis humeri artery.

T. Transversalis colli artery.

U. Union of the post scapu