404 



DR. C. F. SONNTAG ON THE ANATOMY, 



The left thoracic vagus (text-fig. 45 B) has the same relations 

 and course till it reaches the posterior aspect of the pulmonary 

 root as in Man. It gives ofl" recurrent (e), cardiac (/), and 

 anterior pulmonary nerves. Behind the root of the left lung it 

 gives off posterior pulmonary nerves. It does not hreak up into 

 the posterior pulmonary plexus as it does in Man. Leaving the 

 back of the root of the lung it gains the front of the cesophagus, 

 which position it maintains into the abdomen. It supplies the 

 oesophagus and pleura and communicates with the right vagus. 



The right thoracic vagus (text-fig. 45 B) gets into the thorax 

 after crossing the right subclavian artery, at which point it gives 

 off its recuiTent branch. It crosses the right side of the trachea 



Text-figure 45. 



The vagus and sympathetic nerves. A : cervical parts of the left vagus and sympa- 

 thetic; B : thoracic parts of the left vagus and the cervical and thoracic 

 parts of the right vagus and sympathetic. Letters in text. 



from before backwards and it is crossed by the vena azygos major. 

 It passes down the back of the right pulmonary root and inclines 

 downwards and backwards to reach the dorsal aspect of the 

 oesophagus. There is no plexus guise. It gives off three cardiac 

 nerves (/), three anterior pulmonary {g), two tracheal (T.B), 

 two posterior pulmonary (A), and several oesophageal nerves. 



Abdominal Parts of the Vagi (text-fig. 46) : — The left vagus 

 passes through the anterior part of the oesophageal opening in 

 the diaphragm, and divides into two. One branch divides into 

 twigs which run along the lesser curvature as far as the pyloric 

 antrum. The other branch gives twigs along the lesser curvature, 



