Bones of the Skull. 



11 



Squama 

 temporalis 



Processus zygomaticus 



Facies cerebralis 



Incisura parietalis 



Fissura petrosquamosa 

 Eminentia arcuata 



Tuberculum articulare 



Pars tympanica 



Vagina processus styloidei 



Processus mastoideus 



Facies anterior pyramidis 



Hiatus canalis facialis 



/ Apertura superior canaliculi tympanici 

 / Sulcus n. petrosi superficialis minoris 

 Sulcus n. petrosi superficialis majoris 

 Iinpressio trigemini 



__ Apex pyramidis 



Foramen caroticum internum 



Semicanalis m. tensoris tympanH ,-, ,. 

 Septum canalis musculotubarii \ mu sculo- 



tubarius 



Semicanalis tubae anditivae 

 Processus styloideus 



10. Right temporal bone, os temporale, fron^in front. 



The fades anterior pyramidis (see also Figs. 8, 11, 63 and 64) is smooth and 

 directed obliquely from behind and above, forward and downward. Laterally it is fused with 

 the squama temporalis through the fissura petrosquamosa, where it goes over gradually into 

 the cerebral surface of the squama. The free, rough, anterior margin is the angulus anterior; 

 it forms an angle with the margo sphenoidalis of the squama in which fits the posterior angle 

 of the large wing of the sphenoid bone. In this angle lies the opening of the canalis mus- 

 culotubarius, directed forward and medianward ; this canal is divided, usually incompletely, by 

 means of a leaflet of bone, projecting from its medial wall, the septum canalis musculotubarii, 

 into a smaller upper part, the semicanalis m. tensoris tympani (0. T. canal for tensor tympani 

 muscle) and a larger inferior part, the semicanalis tubae auditivae (0. T. canal for the Eustachian 

 tube). The anterior surface is bounded behind by the angulus superior (p. 9). Projecting at 

 a point somewhat lateralward from the middle of the superior surface, near the posterior angle, 

 is the eminentia arcuata (0. T. eminence for superior semicircular canal) caused by the canalis 

 semicircularis superior. The smooth region a little lateral from and in front of this is called 

 the tegmen tympani since it covers the cavum tympani above. Still further forward two open- 

 ings can be seen and two grooves running forward from them ; the medial opening, hiatus 

 canalis facialis (0. T. hiatus Fallopii) , leads through a short canal to the geniculum canalis 

 facialis and contains the r. petrosus superficialis a. mening, med. and the n. petrosus superfic. 

 maj., the latter passing further forward in the medial groove called the sulcus n. petrosi super- 

 ficialis majoris; the lateral, smaller, opening, sometimes fused with the medial, is known as 

 the apertura superior canaliculi tympanici (0. T. opening for smaller petrosal nerve) through 

 which run the a. tympanica superior and the n. petrosus superfic. min. in order to pass further 

 on in the smaller, lateral, groove, the sulcus n. petrosi superficialis minoris. On the upper 

 surface near the apex of the pyramid lies the impressio trigemini (0. T. depression for Gas- 

 serian ganglion) for the n. trigeminus. In addition the facies anterior presents shallow juga 

 cerebralia and impressiones diyitaiae. 



