52 ANATOMY OP THE HEAD AND NECK. 



vein is sometimes called the internal cephalic, and below 

 that point the internal jugular. Below the hyoid bone, it 

 passes downward, parallel with and to the outer side of the 

 common carotid artery, to join the subclavian vein, and with 

 that forms the vena imiominata. At the lower part of the 

 neck its position corresponds to the interval between the 

 sternal and clavicular attachments of the sterno-mastoid 

 muscle. 



The PNEUMOGASTRIC NERVE emerges from the jugular 

 foramen, and will be recognized by the ganglion (ganglion of 

 the trunk) peculiar to it; this is nearly an inch in length, and 

 is surrounded by small nerves. The nerve lies between the 

 jugular vein and internal carotid artery, and communicates 

 with the hypoglossal, spinal accessory, and sympathetic 

 nerves ; it distributes branches to the parts about it, giving 

 off a pharyngeal branch which unites with the glosso- 

 pharyngeal nerve, and with which it forms a plexus on the 

 pharynx; the superior laryngeal branch, of considerable 

 size, passes inside the internal carotid artery to the larynx, 

 which it enters between the hyoid bone and thyroid carti- 

 lage, perforating the thyro-hyoid membrane, and supplies 

 the crico-thyroid muscle ; it also gives off cardiac branches, 

 which unite with those of the sympathetic. 



The GLOSSO-PHARYNGEAL NERVE also escapes from the 

 jugular foramen, and should be traced up to its ganglion, 

 the ganglion petrosum or ganglion of Andersch, which lies 

 close to the bone, and from which emanate the branches 

 which unite it with the other nerves of this region. This 

 nerve crosses over the internal carotid to the lower border 

 of the stylo-pharyngeus muscle ; it there assumes an almost 

 transverse direction to the pharynx, and finally passes 

 under the hyo-glossus muscle, to be distributed to the pha- 

 rynx, tongue, and tonsil. 



The SPINAL ACCESSORY NERVE, blending with the trunk 

 of the pneumogastric, issues from the foramen jugulare, 

 and is connected by small branches with the other nerves 

 of this region. It passes outward, either over or under the 

 jugular vein, to perforate the sterno-mastoid muscle at its 

 upper part, and, uniting with the anterior cervical plexus, 

 is distributed to the trapezius muscle (p. 41). 



The INTERNAL CAROTID ARTERY ascends vertically from 

 the upper border of the thyroid cartilage to the base of 

 the skull ; the rectus capitis anticus major muscle separates 

 it from the vertebrae ; except at its commencement, where 



