The Superior Artery of the cerebellum arises at the anterior margin of the pons, winds round the crus cerebri, accompanying the posterior artery of the cerebrum, from which it is separated, first by the third nerve, next by the fourth; and lastly, by the tentorium. Having reached the superior surface of the cerebellum, it divides into a great number of branches, some of which pass over the tentorium to the inferior surface of the brain; but the greater number pass under the tentorium to the superior surface of the cerebellum, where, after minutely subdividing, they are distributed to the pia mater, and anastomose with the branches of the inferior artery of the cerebellum. In this course it supplies the pons Varolii, crus cerebri, tubercula quadri-gemina, pineal gland, velum interpositum, choroid plexus, and the valve of Vieussens: one branch of it may be observed to enter the internal auditory foramen, separating the facial from the auditory nerve.