Henry Gray (18251861). Anatomy of the Human Body. 1918.
the majority of its fibers are afferent, and are continued onward through the muscular substance of the tongue to the mucous membrane covering its anterior two-thirds; they constitute the nerve of taste for this portion of the tongue. Before uniting with the lingual nerve the chorda tympani is joined by a small branch from the otic ganglion.
The Posterior Auricular Nerve (n. auricularis posterior) arises close to the stylo-mastoid foramen, and runs upward in front of the mastoid process; here it is joined by a filament from the auricular branch of the vagus, and communicates with the posterior branch of the great auricular, and with the lesser occipital. As it ascends between the external acoustic meatus and mastoid process it divides into auricular and occipital branches. The auricular branch supplies the Auricularis posterior and the intrinsic muscles on the cranial surface of the auricula. The occipital branch, the larger, passes backward along the superior nuchal line of the occipital bone, and supplies the Occipitalis.
The Digastric Branch (ramus digastricus) arises close to the stylomastoid foramen, and divides into several filaments, which supply the posterior belly of the Digastricus; one of these filaments joins the glossopharyngeal nerve.
The Stylohyoid Branch (ramus stylohyoideus) frequently arises in conjunction with the digastric branch; it is long and slender, and enters the Stylohyoideus about its middle.
The Temporal Branches (rami temporales) cross the zygomatic arch to the temporal region, supplying the Auriculares anterior and superior, and joining with the zygomaticotemporal branch of the maxillary, and with the auriculotemporal branch of the mandibular. The more anterior branches supply the Frontalis, the Orbicularis oculi, and the Corrugator, and join the supraorbital and lacrimal branches of the ophthalmic.
The Zygomatic Branches (rami zygomatici; malar branches) run across the zygomatic bone to the lateral angle of the orbit, where they supply the Orbicularis oculi, and join with filaments from the lacrimal nerve and the zygomaticofacial branch of the maxillary nerve.
The Buccal Branches (rami buccales; infraorbital branches), of larger size than the rest, pass horizontally forward to be distributed below the orbit and around the mouth. The superficial branches run beneath the skin and above the superficial muscles of the face, which they supply: some are distributed to the Procerus, joining at the medial angle of the orbit with the infratrochlear and nasociliary branches of the ophthalmic. The deep branches pass beneath the Zygomaticus and the Quadratus labii superioris, supplying them and forming an infraorbital plexus with the infraorbital branch of the maxillary nerve. These branches also supply the small muscles of the nose. The lower deep branches supply the Buccinator and Orbicularis oris, and join with filaments of the buccinator branch of the mandibular nerve.
The Mandibular Branch (ramus marginalis mandibulæ) passes forward beneath the Platysma and Triangularis, supplying the muscles of the lower lip and chin, and communicating with the mental branch of the inferior alveolar nerve.
The Cervical Branch (ramus colli) runs forward beneath the Platysma, and forms a series of arches across the side of the neck over the suprahyoid region. One branch descends to join the cervical cutaneous nerve from the cervical plexus; others supply the Platysma.
5h. The Acoustic Nerve
The acoustic nerve consists of two distinct sets of fibers which differ in their peripheral endings, central connections, functions, and time of medullation. It is soft in texture and devoid of neurilemma.