558 



THE AUDITORY APPARATUS 



Tympanic Muscles. These are two in number, viz., the 

 stapedius and the tensor tympani. 



The stapedius occupies the interior of the pyramid and the 

 canal which curves downwards from it. The delicate tendon 

 of the stapedius enters the tympanum, through the aperture 

 on the summit of the pyramid, and is inserted into the 

 posterior aspect of the neck of the stapes. It is supplied by 

 a branch from the facial nerve. 



Membrana tympani 



Epitym panic recess / 



Malleus ! 



Cochlea 

 Internal meatus 



Internal carotid 

 Osseous part of auditory tube 

 Base of spine of sphenoid 



Cartilaginous part of 

 auditory tube 

 Otic ganglion 



Nerve to internal pterygoid 



Levator veli palatini 



Lateral recess of pharynx 



Cartilage of auditory tube 



Middle concha - 



Anterior lip of auditory tube - 



Tensor veli palatini 



Inferior concha 



Hamulus 



xternal meatus 

 ympanic plate 



~*9)^f/ 1 Condyle of mandible 



Middle meningeal artery 



7%f - Mandibular nerve 



' External pterygoid 



j. -j-^- -j- Cavity of auditory tube 



' _. _. Internal maxillary artery 

 Internal pterygoid 

 Ramus of mandible 



Buccinator 



FlG. 243. Oblique section of a part of the Head showing the relation 

 of the Auditory Tube. 



The tensor tympani arises from the upper part of the 

 cartilage of the auditory tube and from the contiguous parts 

 of the great wing of the sphenoid and the petrous part 

 of the temporal bone. From its origin it passes postero- 

 laterally, upon the processus cochleariformis and above the 

 osseous part of the auditory tube. In the tympanic cavity 

 the tendon turns at right angles, round the extremity of the 

 processus cochleariformis, and passes laterally, towards the 

 lateral wall of the tympanum, to its insertion into the upper 



