124 THE MEMBRANOUS LABYRINTH, BY PROF. RUDINGER. 



posterior ; and it is very conceivable that, owing to the obliquity 

 of the surfaces, and the greater length of the anterior margin 

 of the base of the stapes, a certain amount of resistance is 

 opposed to the action of the voluntary musculus stapedius. 



The above-mentioned moderately thick borders of the base 

 of the stapes are invested by a lamella of hyaline cartilage, 



Fig. 317. 



Fig. 317. Horizontal transverse section through the base of the 

 stapes at its insertion into the posterior border of the fenestra ovalis. 

 1, Bony margin of the base, with its investment of hyaline cartilage ; 

 3, thin osseous lamella of the basis ; 4, angle between the crus of the 

 stapes and the projecting border of the base ; 5, posterior border 

 of the fenestra ovalis, with its investment of hyaline cartilage ; 6, car- 

 tilage on the vestibular surface of the base, with its perichondrium ; 

 7, ligamentum baseos stapedis vestibulare ; 8, Ligamentum baseos 

 stapedis tympanicum ; 9, layer of elastic fibres ; 10, spaces between 

 the fibres ; 11, osseous trabeculse ; 12 and 13, musculus fixator baseos 

 lis. 



which varies in thickness from O012 0*024 of a millimeter. 

 The hyaline cartilage dips into the inequalities of the bone, 

 in order that here, as in other osseous junctions of the body, the 

 opposite surfaces may be uniformly applied to each other. It is 

 not, however, the anterior and posterior borders of the base of 

 the stapes that are alone invested with cartilage, but a layer of 

 this substance covers the whole vestibular surface of the stapes- 



