VEINS. 433 



The Buccal artery arises just before the orbital hiatus ; it 

 passes between the inferior maxilla and the pterygoid muscles, 

 supplying the molar glands, various muscular branches, and a 

 twig to the fatty cushion of the orbital fossa. 



The Staphyline artery, very small, accompanies the nerv^e of 

 the same name through the staphyline groove to the soft palate. 



The Superior dental artery, a large branch, leaving the orbit 

 through the maxillary hiatus, enters the maxilla, passing through 

 the dental canal, along the tops of the molar fangs ; at the infra- 

 orbital foramen, it divides into two branches, one passing through 

 the foramen to be distributed over the cheeks, anastomosing with 

 the superior labial, the other terminating in the tush and incisors 

 of the upper jaw. The dental gives off an orbital branch to 

 supply the lachrymal sac, and other occular structures. 



The Spheno-palatine artery is a short, thick trunk, which 

 passes through the spheno-palatine foramen, and divides into 

 branches which are distributed over the walls of the nasal 

 chamber. 



palatine artery. 



(Fig. 163. u.) 



The continuation of the internal maxillary is the palatine 

 artery, which gains the posterior part of the hard palate through 

 the palatine foramen ; it then runs in a furrow along the side of 

 the palate, and inosculates with its fellow, forming an arch, from 

 which is given off the palato-labial artery, which passes through 

 the foramen incisivum to assist in supplying the gum and lips. 

 The arterial arch passes under the free extremities of two small 

 cartilaginous processes, one on each side, which are attached 

 posteriorly to the bony palate. 



Veins. 



Veins are vessels which return blood to the cardiac auricles, 

 and consist of two sets — the pulmonary, which transmit arterial 

 blood from the lungs to the left auricle, and the systemic, which 

 convey venous blood from the somatic capillaries to the right 

 auricle. They are larger and more numerous than the arteries. 

 The smallest veins commence at the cajDillaries, and converge to 

 form larger ones, terminating in trunks which enter the heart. 



2 F 



