70 



THE SKULL AND THE BONES OF THE SKULL 



Zygoma 



Processus zygomaticus*---.. 



Articular portion of glenoid fossa 



Facies articularis 



Zygoma 



Processus zygomaticus 



..Epitympanic recess 



Recessus epitympanicus 



SQUAMOUS PORTION OF TEMPORAL BONE SQUAMA TEMPORALIS. 



Posterior tympanic process 



Processus tympanicus posterior 



Anterior tympanic process 



Processus tympanicus anterior ' 



'Posterior tympanic process 



_ -*Processus tympanicus posterior 



"Anterior tympanic process 

 --.._ "Processus tympanicus anterior 

 , , Sulcus mallei 

 'I Sulcus mallei 



TYMPANIC RING ANNULUS TYMPANICUS. 



Tegmen tympani Mastoid antrum 



Tegmen tympani Antrum tympanicum 



Apex of the petrous portion 



Apex pyramidis 

 Canal for tensor tympani muscle., 



Semicanalis m. tensoris tympani 



Tympanum 

 Cavum tympani 



Tegmen tympani Tegmen tympani 



Eminence of the superior seml- 



_,_ Circular canal- Emmentia arcuata 



Hiatus subarcuatus (correspond- 

 ing with the fioccular fossa of 

 r lower vertebrata Fossa subarcuata 



^Apex Of petrous portion Apex pyramid!* 



Internal auditory aperture 



Vurus acu>ticus mternus 



External orifice of the aqueduct of 

 the vestibule 



Apertura externa aqua^ductus vestibuli 



V, V, 



PETROUS PORTION OF TEMPORAL BONE PARS PETROSA (PYRAMIS). 



FIG. 143. SEEN FROM WITHOUT. FIG. 144. SEEN FROM WITHIN. 



THE THREE PARTS OF THE LEFT TEMPORAL BONE FROM AN EIGHT-MONTHS FCETUS (MONTHS 



OF FOUR WEEKS EACH). 



Body-length, 15^ inches. 



Notch of Rivinus 

 Incisura tym- 



panica 



Post, tympanic spine 

 Spina tympanica m. 

 "Posterior tympanic 



process 



"Processus tympani- 

 cus posterior 



Tympanic sulcus 



Sulcus tympanicus 



Squamous portion 

 - of temporal bone 



Squama temporalis 



Epitympanic recess 



"Recessus epitympani- 



*Anterior tympanic process 

 "Processus tympanicus 



anterior 

 Sulcus mallei 

 Sulcus mallei 



Tympanic ring 



Annulus tympanicus 



Articular portion of glenoid 

 fossa Facies articularis 



Zygoma 



Processus zygo-' 

 maticus 



Fissure of Glaser, 



or petrotym- 



panic fissure 



Fissura petro- 



tympanica 



(Glaseri) 



Tympanum 



Cavum tympani 



Tympanic 

 ring 



Annulus 

 tympanicus 



Carotid canal 



Canalis caroticus 

 Inferior surface of petrous portion 

 Facies inferior pyramidis 



Squamous portion 

 of temporal bone 



Squama temporalis 



Notch of Rivinus 



'Incisura tympanica 



(Rivini) 

 Squamosomastoid 



suture 



Sutura squamoso- 

 mastoidea 



Mastoid 

 portion 



Par:, mastoidea 



Stylomastoid 

 foramen 



Foramen stylo- 

 mastoideum 



Vaginal process 



Vagina processus styloidei 



FIG. 145. THE SQUAMOUS PORTION OF THE 

 TEMPORAL BONE AND THE TYMPANIC 

 RING UNITED. SEEN FROM WITHIN. 



From a foetus at term (body-length, 19 inches). 



FIG. 146. THE THREE PORTIONS OF THE 

 LEFT TEMPORAL BONE UNITED. SEEN 

 FROM WITHOUT AND BELOW. 

 From a new-born male infant (body-length, 21 inches). 



Development of the Temporal Bones. 



