THE GANGLIA. 541 



bodies of the vertebrae and the psoas muscle, and a ganglion is 

 generally formed at the place where they join the nerve. 



In its descent on the lumbar vertebrae, the sympathetkvsends 

 off several nerves that unite to the network which descends on 

 the aorta from the plexus above. After passing over the lum- 

 bar vertebras, it descends into the pelvis, close to the sacrum, on 

 the inner side of the great foramina : here it also forms gang- 

 lions and communicates with the sacral nerves, and likewise with 

 the hypogastric plexus. It terminates on the os coccygis, where 

 its minute fibres join those of the opposite side, and form a gang- 

 lion at their place of junction, called the coccygeal ganglion or 

 ganglion impar. 



VOL. ii. 46 



