CERVICOCEPHALIC PORTION OF THE GANGLIATED CORD 1071 



CAVERNOUS PLEXUS 



SUP. MAXILLARY NERVE 



SPHENOPALAHNE 

 GANGLION 



FIRST 



CERVICAL 



NERVE 



the vagus, and to the hypoglossal nerve. A separate filament (jiervus jugularis) 



passes upward to the base of the skull, and subdivides to join the petrous ganglion 



of the glossopharyngeal, and the 



ganglion of the root of the vagus 



in the jugular foramen. 



The internal branches are per- 

 ipheral, and consist of the pharyn- 



geal and laryngeal branches, and 



the superior cardiac nerve. 



The pharyngeal branches (rami 



pharyngei) (Fig. 780) pass in- 

 ward to the side of the pharynx, 



where they join with branches 



from the glossopharyngeal, 



vagus, and external laryngeal 



nerves to form the pharyngeal 



plexus. 



The laryngeal branches join 



the superior laryngeal nerve and 



its branches. 



The superior cardiac nerve (n. 



cardiacus superior) (Figs. 780) 



arises by two or more branches 



from the superior cervical gan- 

 glion, and occasionally receives 



a filament from the cord of 



communication between the first 



and second cervical ganglia. It. 



runs down the neck behind the 



common carotid artery, lying 



upon the Longus colli, and 



crosses in front of the inferior 



thyroid artery and recurrent 



laryngeal nerve. 



The course of the nerves on 



the two sides then differs. The right superior cardiac nerve, at the root of the 



neck, passes either in front of or behind the subclavian artery, and along the in- 

 nominate artery, to the back part of the 

 arch of the aorta, where it joins the deep 

 cardiac plexus. It is connected with other 

 branches of the sympathetic; about the 

 middle of the neck it receives filaments 

 from the external laryngeal nerve; lower 

 down it obtains one or two twigs from the 

 vagus, and as it enters the thorax it is 

 joined by a filament from the recurrent 

 laryngeal. Filaments from the nerve com- 

 municate with the thyroid branches from 

 the middle cervical ganglion. 



The left superior cardiac nerve, in the 

 thorax, runs by the side of the left common 



carotid artery, and in front of the arch of the aorta to the superficial cardiac plexus. 

 The anterior branches (nn. carotid externi) (Fig. 782) ramify upon the external 



carotid artery and its branches, forming around each a delicate plexus, on the 



LOWER CERVICAL 

 GANGLION 



FIG. 782. Diagram of the cervical sympathetic cord. 

 (Testut.) 



MIDDLE CERVICAL GANGLION 



FIG. 783. The subclavian loop passing from the 

 middle to the inferior cervical ganglia. 



