Mastoid 

 foramen 



Tympanum 

 Prominence of the facial canal 



Depression for the 

 Gasserian ganglion 



Carotid canal ; 



: T . . . Emm :nce for the superior 



: Lateral Sinus semicircular canal 



Mastoid cells 



Tympanic Eminentia articularis 

 plate i 



Glenoid fossa 



External auditory meatus 



Mastoid cells 



Epitympanic recess 



Eminence for superior semicircular canal 

 Prominence of facial canal 

 Promontory 



; Hiatus canalis facialis 



Carotid canal 



Fig. 2}. 



Mastoid process 



External 

 auditory 

 meatus 



Annulus 

 tympanicus 



Canal for 

 Eustachian tube 



Pars tympanica 



