XXX] EAR 231 



irregular cells, not perpendicular to the membrane, 

 but bending inwards, with short hair-like processes 

 projecting from the surface, and deeply seated nucleus ; 

 occasionally two nuclei are seen in a cell. 



e. The supporting cells between the basilar part 

 of the outer hair cells, each sending a thin process up 

 to the reticular membrane. 



f. The rings of the reticular membrane surrounding 

 the tops of the outer and inner hair cells. 



g. Cells passing from columnar to cubical, inclining 

 inwards, like the outer hair cells. 



The membrana tectoria proceeding from a pro- 

 jection of tissue on the lamina spiralis, thence enlarging 

 and forming a more or less distinct pad above the 

 orgaft of Corti ; in the preparation it will probably be 

 considerably shrunken. 



The nerves running along the lamina spiralis towards 

 the basilar membrane, and (if the section passes through 

 the modiolus) the group of nerve-cells cochlear 

 ganglion at the base of the lamina spiralis. 



4. Break the cochlea of a mammal in two, place the pieces 

 in -5 p.c. osmic acid for two hours ; break up the cochlea into 

 smaller pieces, wash with water for an hour or two ; place in 

 picrocarmine for an hour ; under a dissecting lens, separate 

 portions of the membranous tube and tease them out in dilute 

 glycerine ; observe the isolated fragments and cells of the organ 

 of Corti. 



