168 



SYMPATHETIC NERVE. 



leg, through the peroneus longus muscle, and becoming superficial 

 in the lower third of the leg, is distributed to the integuments of the 

 foot and ankle. The anterior tibial descends in front of the interos- 

 seous ligament, in company with the anterior tibial artery, and is 

 distributed to the muscles upon the foot. 



SYMPATHETIC NERVE. 

 The sympathetic system consists of two chains of ganglia, united 

 to each other and to the cranial and spinal nerves. Each ganglion 

 may be considered as a distinct nervous centre, and is placed oppo- 

 site the intervertebral space. The two halves of the sympathetic 

 system are united in the head by the ganglion of Ribes, which may 

 be considered as the origin of the sympathetic nerve. There is also 

 a ganglion in the median line of the coccyx, whereby the two lateral 

 halves of the sympathetic are united. It is distributed in connexion 

 with all the other nerves of the body, and by means of plexuses 

 supplies all the internal organs ; these plexuses take the name of the 

 artery with which they are connected. 



Fig. 146. 



The cranial ganglia of the sympathetic are five in number, viz. : 

 ganglion of Kibes^ which is small and situated upon the anterior 

 communicating artery ; a filament of it^ joins the sixth nerve,^ which 

 communicates with the carotid plexus.^ The carotid plexus surrounds 

 the carotid artery in the carotid canal, and frequently contains a gan- 

 glion called after Lauinonier. This plexus is joined by the deep 

 petrous branch of the vidian nerve, and was formerly considered the 

 origin of the sympathetic. The lenticular ganglion is small and 



