122 A MANUAL OF ANATOMY. 



The sphenomaxillary, or third portion : 



(1) Branches which supply the molar and bicuspid teeth, 

 mucous membrane of the antrum, and twigs to the gums, 

 given off from the internal maxillary upon the back of the 

 superior maxilla. 



(2) The infra-orbital. This runs forward with the superior 

 maxillary nerve through the infra-orbital canal, and appears 

 upon the face through the infra-orbital foramen, where it 

 breaks up into branches to the surrounding muscles and in- 

 tegument of the upper lip, lower eye-lid, and to the lachry- 

 mal sac. 



Within the canal it supplies orbital branches to inferior 

 oblique and rectus muscles ; the anterior dental, to the 

 canine and incisive teeth and mucous membrane of the 

 antrum ; and the nasal branch to the mucous membrane of 

 the nose. 



(3) The superior palatine artery. Its course is down 

 through the posterior palatine canal, along the roof of the 

 mouth, and up through Stenson's foramen into the nose 

 to anastomose with the nasopalatine artery. It supplies 

 the soft palate, tonsils, and mucous membrane of the 

 mouth. 



(4) The Vidian artery. Runs backward through the 

 Vidian canal, supplying the Eustachian tube and roof of 

 pharynx. 



(5) The pterygopalatine. A twig through the pterygo- 

 palatine canal to the roof of the pharynx. 



(6) The nasal, or nasopalatine. Passes through the 

 sphenopalatine foramen to supply the ethmoidal cells, 

 frontal sinus, and antrum. The continuation of the artery 

 extends forward and downward upon the vomer and termi- 

 nates by anastomosing with the anterior terminus of the 

 superior palatine artery, through Stenson's foramen. 



