594 SYMPATHETIC NERVE. 



CEPHALIC POKTION OF THE SYMPATHETIC. 



The cephalic portion of the sympathetic consists of four ganglia. 1. The oph- 

 thalmic ganglion. 2. The spheno-palatine or Meckel's ganglion. 3. The otic or 

 Arnold's ganglion. 4. The submaxillary ganglion. 



These have been already described in connection with each of the three divi- 

 sions of the fifth nerve. 



CERVICAL PORTION OF THE SYMPATHETIC. 







The cervical portion of the sympathetic consists of three ganglia on each side, 

 which are distinguished according to their position, as the superior, middle, and 

 inferior cervical. 



The SUPERIOR CERVICAL GANGLION, the largest of the three, is placed opposite 

 the second and third cervical vertebrae, and sometimes as low as the fourth or fifth. 

 It is of a reddish-gray color, and usually fusiform in shape ; sometimes broad, and 

 occasionally constricted at intervals, so as to give rise to the opinion, that it con- 

 sists of the coalescence of several smaller ganglia. It is in relation, in front, with 

 the sheath of the internal carotid artery, and internal jugular vein ; behind, it 

 lies on the Eectus capitis anticus major muscle. 



Its branches may be divided into superior, inferior, external, internal, and 

 anterior. 



The Superior branch appears to be a direct continuation of the ganglion. It is 

 soft in texture, and of a reddish color. It ascends by the side of the internal 

 carotid artery, and, entering the carotid canal in the temporal bone, divides into 

 two branches, which lie, one on the outer side, and the other on the inner side, of 

 that vessel. 



The outer branch, the larger of the two, distributes filaments to the internal caro- 

 tid artery, and forms the Carotid Plexus (described on page 595). 



The inner branch also distributes filaments to the internal carotid, and, continu- 

 ing onwards, forms the Cavernous Plexus (described on page 595). 



The Inferior or Descending branch of the superior cervical ganglion communi- 

 cates with the middle cervical ganglion. 



The External branches are numerous, and communicate with the cranial nerves, 

 and with the four upper spinal nerves. Sometimes, the branch of the fourth spinal 

 nerve may come from the cord connecting the upper and middle cervical ganglia. 

 The branches of communication with the cranial nerves consist of delicate filaments, 

 which pass from the superior cervical ganglion to the ganglion of the trunk of the 

 pneumogastric, and to the ninth nerve. A separate filament from the cervical 

 ganglion subdivides and joins the petrosal ganglion of the glosso-pharyngeal, and 

 the ganglion of the root of the pneumogastric in the jugular foramen. 



The Internal branches are three in number: pharyngeal, laryngeal, and the 

 superior cardiac nerve. The pharyngeal branches pass inwards to the side of the 

 pharynx, where they join with branches from the pneumogastric, glosso-pharyn- 

 geal, and external laryngeal nerves, and assist in forming the pharyngeal plexus. 

 The laryngeal branches unite with the superior laryngeal nerve and its branches. 



The superior cardiac nerve will be described in connection with the other cardiac 

 nerves. 



The Anterior branches ramify upon the external carotid artery and its branches, 

 forming round each a delicate plexus, on the nerves composing which small 

 ganglia are occasionally found. These ganglia have been named, according to 

 their position, intercarotid (one placed at the angle of bifurcation of the common 

 carotid), lingual, temporal, and pharyngeal. The plexuses accompanying some of 

 these arteries have important communications with other nerves. That sur- 

 rounding the external carotid is connected with the digastric branch of the facial ; 

 that surrounding the facial communicates with the submaxillary ganglion by one 

 or two filaments; and that accompanying the middle meningeal artery sends 



