Diseases of the nervous system / edited by Archibald Church.

Date:
1908
Catalogue details

Licence: In copyright

Credit: Diseases of the nervous system / edited by Archibald Church. Source: Wellcome Collection.

    49/1256 (page 21)
    rior eminence in man is exceedingly small compared with that of the lower animals, for its function as the center of the optic nerve is almost entirely merged in that of the occipital lobe and the thalamus opticus. Immediately below its center is the narrow posterior continuation of the third ventricle, the aqueduct of Sylvius', at either side extending downward is the region of the Fig. 14.—The Cerebellum from the Dorsal Side. (After Edinger.) tegmentum which, as we have just seen, is separated from the foot of the cerebral peduncles by the substantia nigra. The posterior eminences appear macroscopically to be more sharply defined than the anterior. In all trans- verse sections of the corpora quadrigemina the red nucleus may be recognized as a round red structure, lying dorsally from the aqueduct of Sylvius and near the median line; in this structure generally terminates the brachium conjunctivum which comes from the cerebellum and has just crossed it. Be- tween the two red nuclei are the nuclei and fiber bundles of the third cranial nerve, the oculomotor, the exit of which at the base of the brain will be later described, and behind it are the nuclei of the trochlear nerve. The aqueduct of Sylvius after dilating becomes posteriorly the fourth ven- tricle, the rhomboid fossa, the roof of which is formed by the cerebellum, the floor and sides by the continuation of the foot and tegmentum of the mid- brain which form the pons. The foot of the cerebral peduncle is here covered by large, transverse, running masses of fibers and is permeated by them, while the tegmental fibers deceive their peculiar configuration from the disappear- ance of the red nucleus and by the passing to and fro of the fibers from the cerebellum. The cerebellum itself bears undoubtedly an alternate relation to the cere-