DEEP CERVICAL REGION. 51 



superior maxillary bone, sending branches through small foramina to 

 the teeth, the antrum, and the mucous membrane of the gums. 



The infra-orbital branch is the terminal portion of the internal maxil- 

 lary artery ; from the spheno-maxillary fossa it enters the infra-orbital 

 canal with the superior maxillary nerve, and emerges on the face at 

 the infra-orbital foramen (p. 19). 



The remaining branches of the internal maxillary artery are of very 

 small size, and, like the branches of the superior maxillary nerve, 

 which they accompany, are incapable of demonstration, except by a 

 special dissection. 



The internal maxillary vein receives the veins corre- 

 sponding to the branches of the artery, and unites with 

 the temporal vein in a trunk, called the temporo-maxillary, 

 which is one of the principal in forming the external jugu- 

 lar vein ; the veins of the region form a plexus between the 

 two pterygoid muscles. 



The STYLO-GLOSSUS MUSCLE will be found, as its name 

 implies, arising from the apex of the styloid process of the 

 temporal bone ; it is crossed by the gustatory nerve, and 

 is inserted into the side of the tongue. 



The STYLO-PHARYNGEUS MUSCLE lies below the preced- 

 ing ; it arises from the base of the styloid process, and is 

 inserted into the pharynx and upper border of the thyroid 

 cartilage ; it passes between the external and internal caro- 

 tid arteries, and the glosso-pharyngeal nerve turns over 

 the lower part of its fleshy belly. 



Between the stylo-glossus and stylo-pharyngeus muscles 

 is a fibrous band, connecting the tip of the styloid process 

 with the lesser cornu of the os hyoides ; it is called the 

 stylo-hyoid ligament, and is sometimes cartilaginous, or 

 even osseous, in a part or the whole of its extent. 



The styloid process is now to be cut through at its base, and with 

 the two muscles just described turned downward ; the fascia surround- 

 ing the internal carotid artery and the internal jugular vein is to be 

 removed without disturbing the nerves in the vicinity of those ves- 

 sels ; they are the pneumogastric, glosso-pharyngeal, hypoglossal, 

 sympathetic, and spinal accessory. 



DEEP CERVICAL REGION. 



THE INTERNAL JUGULAR VEIN is in close connection with, 

 and lies upon the outer side of, the internal carotid artery'; 

 it emerges from the skull at the foramen jugulare, as the 

 continuation of the lateral and petrosal sinuses ; at about 

 the level of the os hyoides its size is considerably increased 

 by the junction with it of the facial, lingual, thyroid, and 

 occipital veins. Between the skull and h}'oid bone, this 



