INTERNAL MAXILLARY. PHARYNGEAL. 357 



the upper molar and bicuspid teeth, besides ramifying in the lining membrane of 

 the maxillary sinus. Other small branches supply the gums. 



(6) The infraorbital artery runs horizontally forwards into the infraorbital canal, 

 and having traversed that canal along with the superior maxillary nerve, emerges 

 upon the face at the infraorbital foramen. 



Whilst still in the canal, it sends upwards into the orbit small branches, which 

 enter the inferior rectus and the inferior oblique muscle of the eye and the lachrymal 

 gland, and others downwards to supply the front teeth. On the face it gives branches 

 upwards, to the lachrymal sac and inner angle of the orbit, anastomosing with the 

 nasal branches of the ophthalmic and facial arteries, and sends other branches down- 

 wards, beneath the levator labii superioris, which join the ramifications of the trans- 

 verse facial, buccal, and superior coronary arteries. 



(c) The descending or superior palatine artery descends perpendicularly through 

 the posterior palatine canal, with the palatine nerve, and runs along the hard palate. 

 In front it ends in a small vessel which ascends through the incisor foramen, and 

 anastomoses with the artery of the septum. While descending in the canal, this 

 artery sends off twigs through the bone, which communicate on the soft palate with 

 the ascending palatine artery. 



(d) The Yidian branch traverses the Vidian canal with the nerve of the same 

 name ; it is distributed to the Eustachian tube and the top of the pharynx, and sends 

 a small vessel into the tympanum. 



(e) The pterygo-palatine, a very small branch, passes backwards through the 

 pterygo-palatine canal to reach the top of the pharynx, to which, and to the Eusta- 

 chian tube and sphenoidal cells, it is distributed. 



(/) The nasal or spheno-palatine artery enters the spheno-palatine foramen, and 

 divides into two or three branches, some of which ramify extensively over the 

 spongy bones, while others supply the posterior ethmoidal cells and the antrum. 

 One long branch, the artery of the septum, runs forwards along the septum nasi, ends 

 in a small vessel which enters the incisor foramen, and inosculates with the descending 

 palatine artery. 



PECULIARITIES. Origin. The internal maxillary artery is very constant in its place 

 of origin. It has, however, been seen to arise from the facial. 



Course. The artery often passes under cover of the external pterygoid muscle, 

 crossing the inferior maxillary division of the fifth nerve. It has likewise been 

 observed to issue from under cover of the external pterygoid by piercing the middle 

 of that muscle. When the artery is placed beneath the muscle, it has been found 

 lodged in a notch in the posterior margin of the external pterygoid plate, and bound 

 down by fibrous structure. 



Branches. The middle meningeal artery occasionally furnishes the lachrymal 

 artery (usually an offset of the ophthalmic), a peculiarity which may be looked on 

 as resulting from the enlargement of an ordinary anastomosing branch. 



In a case in which the internal carotid artery was wanting, two tortuous branches 

 from the internal maxillary entered the skull by the foramen rotundum and foramen 

 ovale, to supply its place. (Quain " On the Arteries," pi. 13, fig. 8.) 



VIII. ASCENDING PHARYNGEAL ARTERY. 



The pharyngeal artery, long and slender, the smallest branch of the 

 external carotid which has received a distinctive designation, arises most 

 commonly from half an inch to an inch above the origin of the external 

 carotid ; and in its straight course upwards rests on the rectus capitis 

 anticus, close to the surface of the pharynx, between it and the internal 

 carotid artery, and is thus directed up towards the base of the skull. 



BRAJSCHES. These are very small, and may be divided into three sets, 

 viz., those to the pharynx ; a set directed outwards ; and meningeal branches. 



(a) The pharyngeal branches pass inwards, for the most part, to the pharynx. One 

 or two small and variable branches ramify in the middle and inferior constrictor 

 muscles. Higher up than these is a larger and more regular branch, which runs 



