Bell, Charles: The anatomy of the brain: explained in a series of engravings (London, 1802)

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munication betwixt them. By others, it is called Vulva, from
its appearance upon raising the Fornix in the usual manner of
dissecting the Brain,
p. The third Ventricle. The remains of the Comissura Mollis
are scarcely to be observed after the separation of the Thalami
Nervorum Opticorum—therefore it is not represented in the
draw ing ; but we can understand that it is the union of the Tha-
lami above the letter P. and that the space under it is the third
Ventricle. This is a gutter-like cavity communicating or con-
tinued into that common space under the anterior Crura of the
Fornix, and at the same time opening downwards into the In-
fundibulum, and backwards by the Iter ad quartum Ventri-
culum.

A Probe, introduced from the bottom and fore part of the third
Ventricle into the Infundibulum, and which is here repre-
sented as reaching nearly to the surface of the Glandula Pi-
tuitaria.

r. The Glandula Pituitara, seated in the Sella Turcica,
s. The Iter ad quartum Ventriculum.

t. The Comissura Posterior, the connection of which with the

Pineal Gland is accurately represented,
v. The Pedunculi of the Pineal Gland prolonged upon the

Thalamus Nervi Optici.
u. The Tubercula Quadrigemina, or Nates and Testes,
w. Valvula Vieussenii.
x. The Pineal Gland,
y. The Cavitiy of the Fourth Ventricle1.

1 In the buck part of the fourth Ventricle, on each side, we find the little Plexus
Choroides of this Ventricle, which are formed by a small branch from the Vertebral
Arteries.