THE GLENOID FOSSA 



71 



This fossa is mainly of interest on account of its relation to the sphenopalatine 

 (Meckel' sj ganglion. The various foramina and canals connected with the fossa 

 serve for the transmission of the nerves connected with this ganglion and the 

 terminal l)ranches of the internal maxillary artery. 



In addition to the fossae, the lateral region presents the glenoid fossa with its 

 articular eminence, the external auditory meatus, the mastoid and styloid processes, 

 and the following sutures: — 



The spheno-parietal, which lies between the greater wing of the sphenoid and 

 the anterior inferior angle of the parietal. 



The squamous is formed by the squamosal overlapping the lower border of the 

 ])arietal. 



The parieto-mastoid, which lies between the posterior inferior angle of the 

 parietal and the mastoid portion f»f the petrosal. 



Tlie zygomatic suture is formed by the union of the zygoma with the malar bone. 



The squamo- sphenoidal is situated between the anterior border of the squamo- 

 sal and the greater wing of the sphenoid. 



The spheno-malar suture is formed by the orVjital process of the malar and the 



Fig. 80.- 



-A Sectiox of the Skull, showing the Inner Wall of the Okiut. the Inner 

 Wall of the Antrim, and the Spheno-maxillary Fossa. 



FRONTAL S!NUS 



NASAL BONE- 



NASAL PROCESS OF MAXILLA 

 LACHRYMAL 



LACHRYMAL CANAL 



ORIFICE OF ANTRUM 



INFERIOR TURBINAL 



PALATE BONE 



ANTERIOR NASAL SPINE 



ANTERIOR ETHMOID CANAL 

 POSTERIOR ETHMOID CANAL 



OPTIC FORAMEN 



OS PUNUM OF ETHMOID 



-4^ VIDIAN CANAL. LEADING INTO THE 

 SPHENO-MAXILLARY FOSSA 

 SPHENOID 



/- EXTERNAL PTERYGOID PLATE 

 — PALATE BONE 



malar ridge on the greater wing of the sphenoid. Near its middle the suture is 

 perforated by the spheno-malar foramen, which allows the temporal branch of 

 the orbital nerve and a branch of the lachrymal artery to escape from tlie orl)it. 

 This foramen in some adult skulls is complete in the malar. 



The fronto-squamosal is an occasional suture; when it is present, the anterior 

 inferior angle of tlie parietal is excluded from the greater wing of the sphenoid. 



The more important regions are: — 



The pterion, which marks the situation of the anterior lateral fontanelle, is 

 the meeting-place of the coronal, .squamous, spheno-parietal, squamo-sphenoidal, 

 and the fronto-squamosal sutures. Freciuently it is occuj)ied in the adult by the 

 epipteric ossicle. 



Th(^ asterion indicates the situation of the posterior lateral fontanelle and 

 marks the confluence of the squamosal, parieto-mastoid. lambdoid, the occipito- 

 mastoid, and occasionally the occipital sutures. Sometimes it is occupied l>y a 

 ^\'ormian bone. 



The stephanion is the spot where the superior temporal ridge cuts the coronal 

 suture. 



The auricular {loint is the centre of the external auditory meatus. 



