732 



Fig. 340. 



ORIGIN AND DISTRIBUTION OF 

 THE EIGHTH PAIR OP 

 NERVES IN MAN. 



THE NERVES. 



little differently. The right passes round the axil- 

 lary artery very obliquely, upwards, outwards, and 

 backwards beneath the mediastinal pleura, to follow 

 the external face of the trachea to above the origin 

 of the bronchi, where this nerve terminates. The 

 left also passes below the brachial trunk ; but 

 instead of turning round the trachea, it merely 

 lies beside that tube, and reaches the root of the 

 lung, after crossing, outwardly, the origin of the 

 two aortae. 



When these nerves arrive above the bifurca- 

 tion of the trachea, they terminate by forming 

 the bronchial plexus and cesopMgeal nerves the 

 latter being prolonged to the stomach and the 

 solar plexus. 



Beneath the jugular ganglion, but in the upper 

 part of the neck, the pneumogastric receives fila- 

 ments from the spinal accessory, ganglion of 

 Andersch, sympathetic, hypoglossal, and the two 

 first cervical. These different nerves cross each 

 other in a very complex manner on the surface 

 of the guttural pouch, the pharynx, and divisions 

 of the carotids, and form the guttural, pharyngeal, 

 and carotid plexuses. 



Distribution. The branches furnished by the 

 pneumogastric on its course are : 



1. Communicating filaments with the superior 

 cervical ganglion. 



2. Pliaryngeal branch. 



3. Superior laryngeal nerve. 



4. Communicating filaments with the inferior 

 cervical ganglion. 



5. Inferior laryngeal nerve. 



We will pass in review these collateral divisions 

 before studying the terminal branches, which are : 

 1 . Those forming the bt onchial plexus. 

 2. Those constituting the oesophageal nerves. 



*> 3 > 4 > Medulla oblongata ; 1, Corpus pyramidale of one 

 side 2 Pons Varolii ; 3, Corpus olivare ; 4, Corpus 



restiforme ; 5, Facial nerve; 6, Origin of glosso- 

 pharyngeal nerve ; 7, Ganglion of Andersch ; 8, Trunk 

 of the nerve; 9, Spinal accessory; 10, Ganglion of pneumogastric; 11, Its plexiform 

 ganglion ; 12, Its trunk ; 13, Its pharyngeal branch, forming the pharyngeal plexus, 

 14, assisted by a branch from the glosso-pharyngeal, 8, and one from the superior 

 laryngeal, 15; 16, Cardiac branches; 17, Recurrent laryngeal branch; 18, Anterior 

 pulmonary branches ; 19, Posterior pulmonary branches ; 20, (Esophageal plexus ; 

 21, Gastric branches ; 22, Origin of the spinal accessory nerve ; 23, Its branches dis- 

 tributed to the sterno-maxillaris and mastoido-humeralis ; 24, Its branches to the 

 trapezius muscle. 



pharyngeal nerve ; 4, Great hypoglossal nerve ; 5, Superior cervical ganglion of the 

 sympathetic ; 6, Pharyngeal nerve ; 7, Superior laryngeal ; 8, External laryngeal ; 

 9, Inferior laryngeal; 10, Cord of the pneumogastric and sympathetic; 11, First 

 cervical nerve, with the loop it sends to the hypoglossus. From Toussaint's work. 



