RELATIONS OF AUDITORY NERVE TO ORGAN OP CORTI. 177 



consists properly of three parallel divisions, which correspond 

 to the three rows of hair cells, in the interspaces of which it 

 runs upon the same plane as the internal band. The inner- 

 most division runs between the row of the external pillars and 

 the first row of hair cells ; the two others in the intervening 

 spaces of the following rows of hair cells. In Man (fig. 334) I 

 have hitherto only seen three divisions of the external band, 

 notwithstanding that here more rows of cells occur, and as 

 Lowenberg has already stated, the spiral fibres are here most 

 easily seen. Very frequently (see fig. 334), in teazed-out spe- 



Fig. 335A. 



f 



Fig. 335 A and B. Two longitudinal sections (spiral sections) of 

 the organ of Corti through the region of the internal hair cells. 

 From the Vesperugo noctula. Magnified 800 diameters. 



A a, Cuticula (section of the internal division of the lamina 

 reticularis) ; b, internal hair cells, of which two possess long some- 

 what shrivelled processes ; c, spiral fibres ; d, granule layer ; e, nerve 

 fasciculi (oblique section) ; /, a few traversing nerve fibres ; g, one such 

 fibre dividing in the granule layer into several fibrils ; h, a longer 

 finer fibre running outwards between the hair cells. 



cimens, we obtain the hair cells still firmly cleaving to the 

 fibrous bands between which they lie ; as yet, however, I have 

 not been fortunate enough to discover any connection existing 

 between the fibres and the cells. 



The fibrils of the spiral bands belong to the most delicate 

 VOL. in. "N 



