THE AUDITORY APPARATUS 



127 



I am inclined to the opinion that the vestibular nerve 

 serves for the conveyance of pitch, while the function of the 

 cochlear nerve is the regulation of quality, or, in other 

 words, the complex modification and superposition of notes 

 upon which articulate speech depends. 



Let us now revert to the organ of Corti. 



First we have it in section from Schafer : 



Section through the Organ of Corti of the Human 

 C0CHI,EA. (G. Retzius). 

 a, lYimbus ; b, Membrana tectoria ; c. Outer hair-cells ; d. Inner hair- 

 cell ; e. Nerve-fibres ; /, Inner rod ; g, Blood-vessel ; h. Basilar mem- 

 brane ; 7, Outer rod ; k, Cells of Deiters. 



And next a vertical section of the first turn of the cochlea 

 from the same source. 



Verticai, Section of the First Turn of the Human 

 CoCHi,EA. (G. Retzius.) 

 sv, Scala vestibuli ; st, Scala tympani ; dc, Canal or duct of the cochlea ; 

 sp.t, Spiral lamina ; n, Nerve fibres ; str.v, Stria vascularis ; R, Section 

 of Reissner's membrane ; /, Limbus laminae spiratis ; mt, Membrana 

 tectoria ; iC, Tunnel of Corti ; btn, Basilar membrane ; hi, he. Internal 

 and external hair-cells. 



