360 



MAMMALIAN ANATOMY 



The maxillary differs from the united maxillary and premaxillary 

 of the cat in being extremely short (Figs. 279, 280) ; the body, 



FIG. 279. 



FIG. 280. 



LEFT MAXILLARY, OUTER VIEW. 



1, body ; 2, tuberosity ; 3, alveolar process ; 4, orbital 

 plate ; 5, nasal process ; 6, nasal notch ; 7, nasal spine ; 

 8, lachrymal groove; 9, entrance of the infraorbital 

 canal ; 10, infraorbital foramen ; 11, orifices of the pos- 

 terior dental canals ; 12, malar process; 13, articulation 

 for the internal angular process of the frontal bone; 

 14, incisor teeth ; 15, canine tooth ; 16, premolar teeth ; 

 17, molar teeth. 



LEFT MAXILLARY, INNER VIEW. 



1, nasal surface of the body ; 2, surface for the palate 

 bone ; 3, alveolar process ; 4, orbital plate ; 5, nasal 

 process; 6, ridge for the articulation of the maxillo- 

 turbinal bone ; 7, nasal spine ; 8, lachrymal groove ; 

 9, antruru ; 10, palatine process ; 11, anterior palatine 

 fossa; 12, tuberosity; 13, articular extremity for the 

 internal angular process of the frontal bone ; 14, incisor 

 teeth ; 15, canine tooth ; 16, premolar teeth ; 17, molar 

 teeth. 



however, is very high and encloses a large cavity, the antrum of 

 Highmore, 1 or maxillary sinus, which opens widely on the nasal 

 surface (Fig. 280). 



The orbital surface (Fig. 279) is elevated far above the alveolar 

 margin, and is not prolonged backward beyond the posterior limit of 

 the palatine process. With the malar it forms the bony floor of the 

 orbit, which ends behind, where the smooth and rounded margin of 

 the surface becomes the anterior border of the superior orbital, or 

 spheno-maxillary, fissure (Fig. 281). A small portion of the anterior 

 border between the lachrymal canal on the inside and the malar artic- 

 ular surface on the outside assists in the formation of the inferior 

 orbital rim ; in the cat, the malar by uniting with the lachrymal 

 excludes the maxillary from this part of the orbital rim. The infra- 

 orbital groove begins at the posterior border, runs forward, and enters 

 the orbital canal, which passes through the bone and terminates in 

 front and below at the infraorbital foramen. 



The posterior surface of the body is also termed the zygomatic 

 surface, since it faces the zygomatic fossa. It is convex, rounded, and 

 pierced near the middle by the posterior dental foramina ; its lower 



1 Highmore (A.D. 1613-1684). 



