1HK NERVE SYSTEM 



above the point of division of the pulmonary artery and behind the aich of thp 

 aorta. It is formed by. the cardiac nerves derived from the cervical ganglia of 

 the sympathetic and the cardiac branches of the recurrent laryngeal and vagus. 

 The only cardiac nerves which do not enter into the formation of this plexus are 

 the left superior cardiac nerve and the inferior cervical cardiac branch from the 

 left vagus. 



The branches from the right side of this plexus pass, some in front of, and others 

 behind, the right pulmonary artery; the former, the more numerous, transmit 

 a few filaments to the anterior pulmonary plexus, and are then continued onward 

 to form part of the right coronary plexus; those behind the pulmonary artery dis- 

 tribute a few filaments to the right auricle, and are then continued onward to form 

 a part of the left coronary plexus. 



The left side of the plexus is connected with the superficial cardiac plexus and 

 gives filaments to the left auricle of the heart, and to the anterior pulmonary 

 plexus, and is then continued to form the greater part of the left coronary plexus. 



The left coronary plexus (plexus coroiiarius posterior') is larger than the right, 

 and accompanies the left coronary artery; it is chiefly formed by filaments pro- 

 longed from the left side of the deep cardiac plexus, and by a few from the right 

 side. It gives branches to the left auricle and ventricle. - 



The right coronary plexus (plexus coronarius anterior) is formed parti v from the 

 superficial and partly from the deep cardiac plexus. It accompanies the right 

 coronary artery, and gives branches to the right auricle and ventricle. 



Although sympathetic filaments enter into the formation of the anterior and 

 posterior pulmonary and the oesophageal plexuses, these are usually regarded as 

 portions of the vagus nerve (p. 1010). 



The Coeliac or Solar Plexus (Plexus Coeliacus) (Figs. 780, 785). 







The cirliac or solar plexus supplies the viscera in the abdominal cavity. It 

 consists of a great network of nerves and ganglia, situated behind the pancreas 

 and the lesser peritoneal cavity and in front of the aorta and crura of the 

 Diaphragm. It surrounds the creliac axis and root of the superior mesenteric 

 artery, extending downward as low as the pancreas and outward to the suprarenal 

 glands. T_his_plexus, and the ganglia connected with it, receive the great, the small, 

 and the least splanchnic nerves of both sides, and some filaments from the right 

 vagus nerve. It distributes filaments which accompany, under the name of 

 plexuses, all the branches from the front of the abdominal aorta. 



Of the ganglia, of which the solar plexus is partly composed the principal 

 are the two semilunar ganglia (ganglia coeliaca) (Figs. 785 and 786), which are 

 sihiated one on each side of the plexus, and are the largest ganglia in the body. 

 They are large, irregular, gangliform masses formed by the aggregation o f smaller 

 ganglia, having interspaces between them. They are situated in front of the 

 mira of the Diaphragm, close to the suprarenal glands: the one on the right 

 side lies beneath the inferior vena cava. The upper part of each ganglion is 

 joined bv the great splanchnic nerve, and to the inner side of each the branches 

 of the solar plexus are connected. The lower portion of each semilunar ganglion 

 is detached, and is named the aorticorenal ganglion. 



From the creliac plexus are derived the following 



Phrenic or Diaphragmatic plexus. Gastric plexus. 



Suprarenal plexus. Splenic plexus. 



Renal plexus. Hepatic plexus. 



Spermatic ) pj exus Superior mesenteric plexus. 



Ovarian j ** Aortic plexus. 



