united to the corpora mamillaria. The descending pillars have
been cut across, and in front of them, near the point of section,
may be observed, on each side, the attachments of the divided
commissura anterior, at the junction between the corpora striata
and'optic thalami. The arrangement of the fibres in the interior
of the ventricles and hemispheres is exhibited. The origins of the
third pair of nerves, from a point behind the corpora mamillaria,
and the origins of the first pair, from the fissura Sylvii and anterior
lobes, are demonstrated. Schloss.
Nos. 29 and 30.—Two small preparations, showing the anatomy
of the third and fourth ventricles, &c. No. 29 gives an accurate
representation of the corpora striata ; the optic thalami, partially
united by the commissura mollis forming the roof of the third
ventricle ; the pineal gland, and its peduncles ; the corpora qua-
drigemina; and the valve of Vieussens forming the roof of the
fourth ventricle, and giving origin to the fourth pair of nerves.
The superior surface of the cerebellum is also represented. No.
30 exhibits the same parts divided by a horizontal section, and
showing, the corpus striatum ; the optic thalami and third ventricle
between them ; the testes, and processes passing therefrom to
the cerebellum ; the fourth ventricle; and the calamus scriptorius.
Schloss.
No. 31.—A beautiful preparation in wax, by M. Dupont,
P a r is : showing. 1st. In the cerebral region; the left half of the
base of the brain; its convolutions covered by arachnoid membrane
and pia mater holding numerous veins; some folds of
the dura mater, &c.
2dly. In the orbital region (the external wall of the orbit removed)
; the globe of the eye; the optic nerve; the lachrymal gland
and ducts; the levator palpebrse superioris; the superior, the
internal, the inferior, and the external recti muscles ; the inferior
oblique; and the superior oblique, with its trochleator tendon.
There are further shown, most satisfactorily—the frontal branch of
the opthalmic division of the fifth pair of nerves, dividing into the
Supra-trochleator, and superciliary ; the nasal branch of the same
nerve furnishing a filament to the lenticular ganglion, and then
dividing, on the upper surface of the optic nerve, into the nasal
twig and the infra-trochleator twig; and the lacrymal branch,,
advancing towards the lacrymal gland, and dividing into several
filaments which enter its structure. Next, the fourth nerve, much
concealed, running along the margin of the superior oblique
muscle, on the orbital surface of which it is distributed. The sixth
nerve, at the outside, ramifying on the ocular surface of the external
rectus. The third nerve, supplying with filaments the
levator palpebrse, the superior, the internal, and the inferior
rectus, and sending a long branch to . the obliquus inferior; and
also a branch from this latter to the posterior inferior angle of the.
lenticular ganglion. The lenticular ganglion is represented, lying
on the outer side of the optic nerve, and opposite the space be-,
tween the superior and external recti muscles, which are pulled
asunder for its exhibition : a filament from the nasal nerve, and
one from that branch of the third pair, which supplies the inferior,
oblique muscle, join it, posteriorly ; and from its anterior margin,
the long, fine, ciliary nerves arise and run forward to the globe of
the eye.
3dly. In the facial region are represented, the nose ; the alveoli
and teeth of the upper jaw ; the membrane of the antrum maxil-
lare; and the passage of ;|the superior maxillary nerve along a
canal in the bone between the antrum and orbit. Between the
antrum, and the ridge of the external pterygoid process posterior to
it, is shown the spheno-maxillary space, at the top of which the
ganglion of Meckel is represented, receiving two short, fine filaments
from the infra-orbital nerve.
And,4thly. In the cervical region are shown, the internal carotid artery
entering and winding through the tortuous canal of the petrous
bone, and accompanied by filaments from the superior cervical
ganglion of the sympathetic nerve, which form, by their union on
the side of the artery, when about half way along the canal, a
small quadrilateral ganglion: on a plane more posteriorly, are represented,
the skin of the scalp, and the cells of the mastoid process;
2 i