size situated on
covered parts of the body, where a scar is of no importance. Its chief
advantages over electrolysis are that a single operation is sufficient,
and that the cure is speedy and certain. The operation is attended with
much less haemorrhage than might be expected.

#Cavernous Angioma.#--This form of angioma consists of a series of large
blood spaces which are usually derived from the dilatation of the
capillaries of a subcutaneous naevus. The spaces come to communicate
freely with one another by the disappearance of adjacent capillary
walls. While the most common situation is in the subcutaneous tissue, a
cavernous angioma is sometimes met with in internal organs. It may
appear at any age from early youth to middle life, and is of slow growth
and may become stationary. The swelling is rounded or oval, there is no
pulsation or bruit, and the tumour is but slightly compressible. The
treatment consists in dissecting it out.

#Aneurysm by Anastomosis# is the name applied to a vascular tumour in
which the arteries, veins, and capillaries are all involved. It is met
with chiefly on the upper part of the trunk, the neck, and the scalp. It
tends gradually to increase in size, and may, after many years, attain
an enormous size. The tumour is ill-defined, and varies in consistence.
It is pulsatile, and a systolic bruit or a "thrilling" murmur may be
heard over it. The chief risk is haemorrhage from injury or ulceration.

[Illustration: FIG. 69.--Cirsoid Aneurysm of Forehead in a boy aet. 10.

(Mr. J. W. Dowden's case.)]

The _treatment_ is conducted on the same lines as for naevus. When
electrolysis is employed, it should be directed towards the afferent
vessels; and if it fails to arrest the flow through these, it is useless
to persist with it. In some cases ligation of the afferent vessels has
been successful.

#Arterial Angioma# or #Cirsoid Aneurysm#.--This is composed of the
enlarged branches of an arterial trunk. It originates in the smaller
branches of an artery--usually the temporal--and may spread to the main
trunk, and may even involve branches of other trunks with which the
affected artery anastomoses.

The condition is probably congenital in origin, though its appearance is
frequently preceded by an injury. It almost invariably occurs in the
scalp, and is usually met with in adolescent young adults.

The affected vessels slowly increase in size, and become tortuous, with
narrowings and dilatations