NEUROLOGY. 129 



sends off tlie tyuipanic branchy and lower down the chorda tymjmni. Escaping 

 through the stylo-mastoid foramen, it gives off three branches, the jioslerior 

 auricular^ stylo-hyoid^ and suhmastoid or digastric. Further branches and 

 subdivisions arc the temporo-facial, with its fasciculi, the temporal, malar, 

 and buccal ; and the cervico-facial, still further separated into maxillary, 

 submaxillar}', and cervical branches. The portio dura nerve has been sup- 

 posed to be the exclusive motor nerve of all the superficial muscles of the 

 face, of the eyelids, nose, mouth, lips, and of the ears. 



7 b. The Auditory Nerve, ok Portio Mollis of the Seventh Pair. 

 This, which is a single nerve of sense, arises partly from the medullary 

 striae, or the surface of the calamus scriptorius, and partly from the corpus 

 restiforme, between the glosso-pharyngeal nerve and the tuber annulare ; it 

 is distributed to the labyrinth of the ear. 



8 a. Glosso-Pharyngeal, or First Branch of the Eighth Pair. 

 This arises from the posterior cord of the medulla oblongata, just above and 

 anterior to the superior filaments of the next nerve. Its filaments, there- 

 fore, spring from the anterior margin of the corpus restiforme, or from the 

 fissure separating it from the corpus olivare. After the union of its fila- 

 ments into a round cord, it passes through the foramen lacerum posterius, 

 and is ultimately distributed to the tongue and pharynx. 



8 b. The Pneumogastric Nerve, or Vagus of the Eighth Pair. 

 This arises from the corpus restiforme of the medulla oblongata, posterior 

 to the highest root of the accessory nerve. It passes through the foramen 

 lacerum posterius, in a canal in common with the spinal accessory, and is 

 separated posteriorly from the internal jugular vein by a small spine of 

 bone. In the foramen it presents a ganglionic expansion, and below it a 

 gangliform swelling, nearly an inch in length ; the latter communicates 

 beneath the base of the cranium, and in front of the two first cervical verte- 

 bra, with the facial, glosso-pharyngeal, spinal accessoiy, sympathetic, and 

 superior spinal nerves, constituting the basilar plexus. Descending towards 

 these organs, it gives off cervical, thoracic, and abdominal branches. The 

 cervical branches are the communicating, the auricular, the pharyngeal, the 

 superior laryngeal, the cardiac, and the recurrent or inferior laryngeal. 

 The thoracic gives off the pulmonary and the oesophageal nerves, the former 

 presenting the anterior and posterior pulmonic plexus, the latter the oeso- 

 phageal plexus. On the right stomach, the right vagus passes behind the 

 cardiac orifice ; and its branches, with some others, unite to form the cardiac 

 plexus. The pneumogastric nerves supply the pharynx, oesophagus, and 

 partly the stomach ; also the larynx, trachea, lungs, and partly the heart ; 

 they are, therefore, concerned in deglutition, voice, respiration, circulation, 

 and digestion, and maintain important sympathies between the different 

 organs concerned in these functions. 



8 c. The Nervus Accessorius, or Spinal Accessory. This is the 

 third branch of the eighth pair. It arises from the posterior fasciculus of 

 the medulla oblongata, just above the hypoglossus nerve, and also from 

 the posterior fasciculus of the medulla spinalis ; with a variable number of 

 roots, it passes through the foramen lacerum posterius, to be distributed to 



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