34 HUMAN ANATOMY. 



The splieno-maxillary fossa is a triangular cavity, bounded 

 above by body of sphenoid and orbital plate of palate-bone, within 

 by vertical plate of palate, in front by superior maxillary, and 

 behind by pterygoid process of sphenoid. It has communicating 

 with it 



Three fossae orbital, nasal, and zygomatic; 



Three fissures sphenoidal, spheno-maxillary, and pterygo- 

 maxillary ; 



Two cavities cranial and buccal; and 



Five foramina foramen rotundum, Vidian, and pterygo- 

 palatine posteriorly; spheno-palatine, on inner wall, and pos- 

 terior palatine canal, and (sometimes) accessory posterior pala- 



FIG. 16. 



2, nasal eminence; 3, supraorbital ridge; 4, lachrymal bone; 5, 

 ethmoid bone; 6, infraorbital groove; 7, lachrymal groove; 9, infra- 

 orbital foramen; 10, malar foramina. 



tine canals below. It contains internal maxillary artery, superior 

 maxillary nerve, and Meckel's ganglion. 



THE ORBITS are two pyramidal cavities, situated between 

 the nose and external angular processes, the forehead and face, 

 their bases outward and forward, their apexes converging toward 

 the body of the sphenoid bone. They contain the eye and its 

 appendages, and are each formed by seven bones frontal, eth- 

 moid, sphenoid (entering into both cavities), and superior maxil- 

 lary, lachrymal, malar, and palate (separate in each). The 

 roof, concave, presents : 



Externally, depression for lachrymal gland; 



Internally, depression for pulley of superior oblique, and 



