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Around the foramen magnum, and forming the back 

 of the skull, is the occipital ; it represents a fusion of the 

 supra-, basi-, and two ex-oocipitals, the last bear the condyles 

 and have descending paroccipital processes (one down the 

 side of each tympanic bulla). The roof of the skull, from 

 the supraoccipital forwards, consists of small interparietal, 

 parietals, frontals, nasals* and premaxillae (bearing the 

 incisor teeth). At the sides of the skull are the premaxillae 

 and large maxillae (bearing premolar and molar teeth, and 

 together forming the upper jaw), lachrymals, orbitosphenoids 

 (around optic foramen), supraorbital processes (crests of 

 frontals above orbits), palatines and pterygoids between 

 these and the alisphenoids, large squamosals (between 

 alisphenoids and parietals), and periotics with outer tym- 

 panics behind. 



The squamosal has, on its outer surface, a stout projecting 

 zygomatic process, which bears ventrally the glenoid fossa 

 for the condyle of the mandible. The maxilla has a similar 

 process ; and the two processes, united by the intervening 

 jugal or malar, constitute the zygomatic arch, which forms 

 a bridge between the temporal fossa and orbit, and serves 

 for the attachment of muscles. 



On the floor of the skull and roof of the mouth are the 

 basioccipital, the basisphenoid, between the alisphenoids 

 and with a dorsal recess (sella turcica) for the pituitary 

 body, the presphenoid (between orbitosphenoids), pterygoids 

 and palatines. The posterior part of the hard palate* is 

 formed by the horizontal front portions of the palatines 

 with the palatal processes of the maxillae united behind ; 

 and similar processes of the premaxillae form the incomplete 

 front part. 



The two nasal cavities, within which are the thin folded 

 turbinals, are separated by the vertical mesethmoid ; it 

 has on its lower edge the slender vomers, and it is expanded 

 behind as the sieve-like cribriform plate, through which the 

 olfactory nerves pass to the nose. 



The periotic (around the internal ear), between the 

 occipitals and squamosal, has an inner petrous portion and 

 an outer mastoid portion. The tympanic, on the outer side 

 of the periotic, consists of an upper funnel-like part (bony 

 wall of external auditory meatus) and a bulbous base, the 

 tympanic bulla, which encloses the tympanic cavity con- 

 taining the ear ossicles. The squamosal, periotio, and 

 tympanic constitute the temporal bone of human anatomy. 



* The soft palate is the muscular bridge between the pterygoids ; 

 it ends in a free border above the glottis, and it separates the posterior 

 nasal chamber from the buccal cavity. 



