414 DR. C. F, SONNTAG ON THE ANATOMY, 



branch to the inferior mesenteric plexus, and the ovarian plexus 

 (O.P). The cord connecting the second and third ganglia gives 

 twigs to the aortic plexvis (A.P). The third ganglion (G.3) 

 lies at the beginning of the common iliac artery. It gives 

 off rami communicantes to the lower two lumbar nerves, 

 hypogastric nerves (H.N) and the external iliac nerves. The 

 fourth ganglion (G.4), situated within the pelvis, gives off 

 strong rami communicantes to the sacral nerves, and a nerve to 

 the hsemorrhoidal plexus. The right cord has two abdominal 

 and one pelvic ganglia. The first ganglion gives rami communi- 

 cantes to the lumbar nerves from its lateral aspect. From its 

 mesial aspect a stout cord comes and divides into an upper 

 branch to the left renal plexus (L.R.P) and a lower bunch of 

 three nerves to the inferior mesenteric plexus (I.M.P). The 

 second ganglion is at the level of the common iliac artery. 



Vagus and Sympathetic Plexuses. 



A. Pharyngeal Plexus : — This is formed by branches of the 

 glossopharyngeal nerve and sympathetic, and the pharyngeal 

 branch of the vagus. 



B. Ca7-diac Plexus (text-fig. 45 B) : — The cardiac plexus lies 

 chiefly between the aortic arch and heart anteriorly, and the 

 trachea posteriorly. It receives two cardiac branches of the 

 left vagus. One rises in the neck and divides into four branches 

 on the front of the aortic arch ; two of the branches pass under 

 the arch to the dee}) part of the plexus, the third runs to the 

 surface of the arch, and the fourth supplies the pulmonary 

 artery. ]S"o sympathetic filaments run over the arch to the 

 superficial part of the plexus (S.C.P). The deep part of the 

 plexus (D.C.P) communicates with the superficial part and 

 receives: — (1) Many filaments from the left sympathetic, a 

 thoracic cardiac branch of the left vagus, the cervical cardiac 

 branch of the right vagus, three thoracic cardiac branches of the 

 right vagus and filaments from the right cervical sympathetic. 

 The plexus contains two clusters of ganglia, one behind the 

 beginning of the innominate artery, and the other between the 

 aortic arch and bifurcation of the trachea. The large vessels 

 arising from the arch have associated plexuses or sympathetic 

 nerve cords. 



C. Anterior pulmonary pleamses derived from the vagi. No 

 separate sympathetic filaments are seen. 



D. Posterior pulmonary plexuses derived from the vagi and 

 upper thoracic ganglia of the sympathetic. 



E. Solar Plexus (text-fig. 46) : — The gangliated ring, which 

 acts as a centre, lies in front and at the sides of the cceliac axis. 

 It receives the greater part of the right vagus (R.V) and the 

 great splanchnic nerve of the left side (Gr.S.N). It gives oft' 

 a tmnk at its lower end which runs into the gangliated cord of 

 the sympathetic of the left side (A.G.C). It gives off the cceliac 



