Protrusor

Anything protruded, or which protrudes. P. labii inferior is, the corrugator muscle of the lower lip. P. linguae. Synonym of Genio-glo us. See:, Table of. (pro-tu'-ber-ans). A knob-like projecting part. P., Annular. Synonym of Pons varolii. P., Cerebral: I i. Synonym of Pons varolii. 2. The prominence formed by the upper or anterior of the cerebral flexures of the embryo. P., External Occipital, the central prominence on the outer surface of the flat por, tion of the occipital bone. P., Frontal: I. The prominence of the frontal bone. 2. The prominence formed by the lower of the two flexures of the cephalic end of the embryo. P., Inferior Maxillary, in the embryo, a prominence formed on each side by a division of the rirst pharyngeal arch, and representing the rudiments of the lower jaw. P., Internal Occipital, a slight central prominence on the inner surface of the tabular portion of the occipital bone. P., Lateral Frontal, an elevation on either side of the frontal prominence of the embryo. P., Mental. A synonvm of Prominence, Mental. P., Natiform, the nates of the corpora quadrigemina. P., Occipital. j See P., External Occipital, and P., Internal Occipital. P., Parietal, the eminence of the parietal bone, situated near the sagittal suture. P., Superior Maxillary, a prominence formed on each side of the embryo by a division of the first pharyngeal arch,