428 SPECIAL ANATOMY. 



Ganglia sacralia (four to five, or six) are very variable in 

 situation, shape, and number, the superior generally the 

 thicker ; they lie close to the exit of the anterior roots of the 

 sacral nerves, from which they receive two thick roots. 

 Branches : 



To art. hypogastrica and their branches, rectum and pelvic 



plexus. 



Plexus sacralis medius commences even upon the fourth 

 lumbar vertebra, descends on the anterior surface of the 

 sacrum, becomes larger as far as the fourth piece of the 

 sacrum, and forms four to five ganglionic circles about the 

 art. sacralis media, becomes more delicate on the coccyx, and 

 terminates in the 



678. Ganglion coccygeum. 



An azygos, small ganglion, in which the most external filaments 

 of the n. sympathici of the two sides blend together. It is situated 

 upon the anterior surface of the coccyx, unites with the coccygeal 

 nerves, and gives several minute filaments to the apex of the os 

 coccyx. 



B. Visceral branches and plexuses. 



679. a. Rami splanchnici (s. pars thoracica). 



1 . Nerv. splanchnicus supremus, is not constant, it arises from 

 the cardiac plexus, and receives roots from the first to the sixth 

 thoracic ganglia. Its course varies, sinking into the vagus, or with 

 the aorta into the abdomen to the plexus mesaraicus superior and 

 renalis. 



2. N. splanchnicus major, arises with many roots from the fifth 

 to the eleventh or all the thoracic ganglia, descends along the verte- 

 bral bodies, becomes flattened, passes between the external or inter- 

 nal and middle crus of the diaphragm (or through hiatus aortic.) 

 in great measure to the gang, semilunare of its own side. The 

 right sends a. portion of its fibres, to the left, towards the spleen ; 

 the left towards the right, so that they cross. 



3. -N. splanchnicus minor, arises from the eleventh or twelfth 

 thoracic ganglion or higher, passes outivards close to 2, sometimes 

 united with it, into the lower part of plex. cozliacus, often also into 

 plex. renalis. 



4. N. splanchnicus inferior s. renalis posterior, arises from the 

 twelfth thoracic ganglion, anastomoses with 3, and passes to plex. 

 ccdiac., renalis, and supra-renalis. 



