454 



THE TISSUES, 

 Fig. 300. 



A highly magnified view of a small piece of the lamina spiralis, showing the manner in which the 

 nerves leave their perineurium as they anastomose ; the natural size of the piece is seen on the side 

 of the figure. 1. Portion of the auditory nerve. 2, 2. Osseous canals in the zona ossea of the lamina 

 spiralis. 3, 3. Anastomoses in the zona mollis. 4, 4. The neurilemma leaving the nervous loops, 

 and expanding into the zona membranacea. 



Fig. 301, 



Bipolar ganglion-cell 

 from the zonula ossea of 

 the lamina spiralis of 

 the pig. Magnified 350 

 diameters. (After Corti.) 



The cochlear nerve, having entered the cavity of 

 the osseous zone from the canal of the modiolus, 

 forms a plexus (Fig. 300) of dark-bordered fibres, 

 suV <y of an inch in diameter, containing an aggre- 

 gation, at a definite spot, of, at first, T |^ of an 

 inch wide, of bipolar, oval, minute ( T oVir to ?f 

 of an inch), and pale ganglion -cells ; and which 

 probably intercept all the fibres of the cochlear 

 nerves in their course. (Fig. 301.) 



The dark-bordered fibres proceeding from the 

 external side of these cells are again disposed 

 in anastomosing, and afterwards in parallel flat- 

 tened bundles. The fibres actually terminate by 

 being pale, Tgi^ f an i ncn i n diameter, and 

 finer; and then ceasing, there being no loops. 

 (Corti.) 



Thus both the auditory and the optic nerves 

 have a ganglion at their periphery, which proba- 

 bly receives the impressions, while the nerve- 

 fibres merely serve to conduct them to the brain. 



