170 



LUMBAR AND SACRAL GANGLIA. 



Its branches form the cardiac plexus in conjunction with the par va- 

 gum and descendens noni ; from this plexus are derived the filaments 

 which supply the heart. 



Fig. 147. 



THORACIC GANGLIA. 



These are twelve in number, situated 

 at the intervertebral spaces. They are 

 small and connected with each as well as 

 with the anterior trunks of the spinal 

 nerves. The great splanchnic^'^ is formed 

 by filaments from the sixth to tho tenth 

 ganglion ; it descends in the posterior medi- 

 astinum, and pierces the diaphragm at or 

 near the foramen aorticum, to form the 

 semilunar ganglion. The lesser splanchnic 

 nerve^^ is formed by filaments from the tenth 

 and eleventh ganglia ; it pierces the dia- 

 phragm and joins the semilunar ganglion 

 and the renal plexus. 



The semilunar ganglion consists of a 

 number of smaller ganglia formed upon fila- 

 ments of the splanchnic nerve after it has 

 entered the abdomen ; they are arranged 

 in a crescentic manner,*^ and situated upon 

 the aorta and coeliac axis. 



The solar plexus is a network on the sides 

 of the aorta, and extending as far as the 

 renal arteries. It is a number of filaments 

 connecting the portions of the semilunar 

 ganglia ; and from it proceed smaller plex- 

 uses, which accompany the large arterial 

 trunks ; thus, the hepatic plexus is the in- 

 tertexture which surrounds the hepatic ar- 

 tery, and is distributed to the liver, gall- 

 bladder, &c. The splenic plexus accom- 

 panies the splenic artery and supplies the 

 spleen ; thus also, is distributed, the renal, 

 mesenteric, and other plexuses. 



LUMBAR AND SACRAL GANGLIA. 



The lumbar ganglia are four or five in number, which are united 

 with eaph other and the spinal nerves. They form a plexus upon 

 the aorta, which receives filaments from the solar and hypogastric 

 plexuses. 



The hypogastric plexus is formed by branches of the lumbar and 

 aortic plexuses and filaments from the sacral ganglia. From it are 

 supplied all the viscera of the pelvis. The sacral ganglia are three 



