THE AUDITORY NERVE 



635 



minal fibrils from these spiral plexuses end in relation with both 

 the inner and the outer hair cells. 



The relation of the nerve cells of the spiral ganglion and the 

 ganglion of Scarpa to the termination of the nerve fibrils about the 



o.h 



i.p. v.s. o.p. 



D 1 



D 3 



B. 



FIG. 459. AXIAL SECTION THROUGH CORTI'S ORGAN OF THE GUINEA-PIG, SHOWING THE 



TERMINAL NERVE FIBRILS. 



B, cells of Bottcher; Z)i, />', Z*, three rows of Betters' cells; H, cells of Hensen ; 

 *.&., inner border cell ; i.h., inner hair cell ; i.p., inner pillar cell ; n, terminal branch of 

 the cochlear nerve; o.h.-l, 2, 3, three rows of outer hair cells; o.p., outer pillar cell; p., 

 phalangeal process of the outer sustentacular process. Very highly magnified. (After 

 Held.) 



hair cells of the organ of Corti, the maculae, and the cristae, is 

 essentially the same. The ganglia contain the cell bodies of the 

 peripheral sensory neurones of the eighth cranial nerve. These 

 are bipolar cells, of which the central process or neuraxis enters a 

 medullated nerve fibre of the auditory nerve, while the peripheral 

 process is distributed to the hair cells of the several areas of special- 

 ized neuro-epithelium, as above described. 



BLOOD SUPPLY. The internal ear is supplied by the internal 

 auditory artery, which enters the labyrinth along with the auditory 

 nerve, and at once divides into two main stems, the vestibular and 

 the cochlear (arteria cochlearis communis, Siebenmann *). The 

 vestibular branch accompanies the branches of the vestibular nerve 

 to the saccule, utricle, and semicircular canals, supplying these 

 structures in the posterior portion of the vestibule, and forming a 

 rich plexus in the connective tissue of the maculae and cristae, and 



* Handbuch der Anat, Bardeleben, Bd. v, Abth. II. 



