TRE GREAT SYMPATHETIC NERVOUS SYSTEM. 783 



ganglion. Their description has been given with that of the fifth encephalic 

 pair of nerves. 



2. Cervical Portion of the Sympathetic. 



The cervical section of the ganglionic chain is formed by two large 

 ganglia placed one at the top, the other at the bottom, of the neck, and united 

 to each other by an intermediate cord. 



A. Superior Cervical or Guttural Ganglion (rig. 362, 1). This 



ganglion is a very elongated fusiform body, lying beside the internal carotid 

 artery, comprised with it in a particular fold of the membrane forming the 

 guttural pouch, and therefore situated in front of the transverse process of 

 the atlas, in proximity to the glosso-pharyngeal, pneumogastric, spinal, and 

 hypoglossal nerves, as well as the inferior branch of the first cervical pair. 

 AH these nerves communicate with the ganglion by slender filaments, and 

 in this way form around it a veritable plexus, which has been designated the 

 guttural plexus by Veterinary Anatomists. 



Afferent Branches. — These are communicating filaments belonging to 

 the nerves already enumerated. They do not possess sufficient importance 

 to merit particular mention. We may notice the existence of the filaments 

 supplied by the inferior branches of the first four cervical nerves. 



Emergent Branches. — These are : 1, Branches accompanying the 

 internal carotid artery into the cranium ; 2, A thicli fasciculus which 

 reaches the origin of the three terminal divisions of the common carotid ; 

 3, Small filaments to the membrane of the guttural pouch and the wall of 

 the pharynx. 



The following are the principal anatomical characters of" these three 

 orders of branches : 



a. The satellite hranches of the internal carotid artery arise at She superior 

 extremity of the ganglion. They may vary in number. We have generally 

 found two of unequal volume — a posterior, and an anterior, which is the 

 smallest. They interlace around the internal carotid in anastomosing with 

 each other, and with that vessel enter the cavernous sinus, where they form, 

 by their divisions, a little plexiform apparatus named the cavernous plexus, 

 the diverse branches of which connect it with several of the encephalic 

 nerves. Among these branches are remarked : 1, Some filaments joined to 

 analogous filaments from the opposite side, on the transverse anastomosis 

 which unites the two internal carotids in the cavernous sinus ; 2, A branch 

 lying beside the great petrosal nerve, and concurring in the formation of the 

 Vidian nerve, which enters the spheno-palatine ganglion ; 3, A ramuscule 

 going to the ophthalmic ganglion, in company with fibres from the 

 ophthalmic branch of the fifth pair; 4, Several filameuts passing to the 

 Gasserian ganglion ; 5, Branches which mix with the fibres of the three 

 motor nerves of the eye. 



h. The inferior carotid fasciculus, destined to the terminal extremity of 

 the common carotid, escapes from the inferior part of the guttural ganglion, 

 I'requently at its origin it is only a thick cord, but ordinarily it is composed, 

 from its commencement, of several branches bound to one another by com- 

 municating filaments. Eeaching their destination, these branches meet 

 ramuscules emanating from the glosso-pharyngeal and pneumogastric nerves, 

 and anastomose with them to form, around the origin of the three terminal 

 branches of the common carotid, the so-called carotid plexus, whose rami- 

 fications almost exclusively follow the external carotid, and the greater part 

 of which are distributed to the glands and the salivary lobules. In Man, the 



