RELATIONS OF AUDITORY NERVE TO ORGAN OF CORTI. 171 



Fig. 331. Vertical section of the organ of Corti in the Dog, magnified 

 800 diameters, a 6, Homogeneous layer of the membrana basilaris ; 

 u, its vestibular layer, corresponding to the striae of the zona pectinata; 

 , tympanal layer, with nuclei, granular cell protoplasm, and intervening 

 sections of fibrils of connective tissue ; a, labium tympanicum of the 

 crista spiralis ; i, continua- j* 



tion of the tympanal peri- \ 



osteum of the lamina spiralis 

 ossea ; c, thickened com- 

 mencement of the membrana 

 basilaris immediately exter- 

 nal to the passage of the 

 nerves, h ; d, vas spirale ; e, 

 bloodvessel ; /, nerve fasci- 

 culi ; g, epithelium of the 

 sulcus spiralis internus (not 

 well preserved); i, an inter- 

 nal hair cell ; k, its basal pro- 

 cess ; surrounding the latter, 

 above the point of emergence 

 of the nerves, are a few nu- 

 clei and a finely granular 

 mass into which the nerve 

 fibres stream (granule layer ) ; 

 I, inner part of the capitular 

 lamina of the internal pillar 

 and hairs of the internal hair 

 cell ; m, capitula of the two 

 pillars joined together, the 

 body of the external pillar, 

 to which the above belongs, 

 cut through its middle ; be- 

 hind it the body and base, o, 

 of the next pillar comes into 

 view ; n, base with nucleated 

 remains of protoplasm of the 

 internal pillar ; p, q^ r, three 

 external hair cells (only traces 

 of the hairs preserved), the 

 first one alone complete, of * 



the two others only the heads are seen ; t, basal portion of two other hair 

 cells ; z, Hensen's supporting cells ; I I, lamina reticularis ; u; a nerve 

 fibre passing to the first hair cell, p, which can be followed beneath the 

 arch to the point of emergence of the nerves. 



