BONES OF THE SKULL. 



Skeleton 0} the Face. Anteriorly this is formed by the su- 

 perior maxillae,, which are united below the nasal aperture. 

 The malar bones lie externally on the malar processes of the 

 superior maxillae, while the nasal bones are wedged in between 

 their frontal processes above. The tooth sockets produce 

 ridges of which the canine is the most prominent; internal to 

 this is a shallow (incisive) fossa over the incisors, while external 

 to it and higher up is a deeper (canine) fossa. Just below the 

 orbital margin is the orifice (infra-orbital foramen) of the infra- 

 orbital canal. The body of the superior maxilla contains a 

 large pyramidal cavity (antrum of Highmore). The alveolar 

 processes are curved and project from the under surface of 

 each body ; they contain the teeth and form together the alve- 

 olar arch. [151] 



The nasal aperture is pyriform. Its margins are formed be- 

 low by the free edges of the bodies and frontal processes of the 

 superior maxilkc, and above by those of the nasal bones. At 

 the centre of its lower margin is an outstanding process (an- 

 terior nasal spine). [152] 



Lateral Aspect (norma lateralis). This includes the frontal, 

 parietal, occipital, sphenoid, temporal, malar, and superior 

 maxilla. A vertical (coronal) suture unites the frontal and 

 parietal. Another (lambdoid) unites the occipital and parietal ; 

 it joins (at the asterion) the occipito-mastoid and parieto- 

 mastoid sutures. The spheno-parietal suture forms (at the 

 pterion) the crosspiece of an H-shaped suture surrounding the 

 end of the great wing of the sphenoid. A ridge (temporal crest), 

 often double, curves upward and backward from the external 

 angular process of the frontal, across (at the stephanion) the 

 coronal suture, then downward over the parietal toward the 

 posterior inferior angle, and then (supramastoid crest) forward 

 on the temporal to become the posterior root of the zygoma. 

 An elevation (parietal eminence) is seen near the centre of the 

 parietal, above the temporal crest. The malar presents an ex- 

 ternal foramen (malar canal) leading into the orbit, and a 



[7] 



