EAR 



475 



the deeper portions of the sustentacular cells. These Nuel's spaces connect 

 with the tunnel. 



Deiter's sustentacular cells are slender bodies, each containing a stiff 

 filament, and having at its free end a cuticular formation referred to as a 

 "phalanx." The phalanges come between the outer hair cells, separating 

 them from one another (Fig. 480), and the inner hair cells are similarly 

 separated by short processes the inner phalanges, derived from the inner 

 pillars. (The inner phalanges are not shown in the figure.) The phalanges 

 of Deiter's cells connect with one another, forming a trim reticular mem- 

 brane. As a whole Deiter's cells resemble the pillar cells, but their trans- 

 formation into stiff fibers has not proceeded so far; the cuticular border is 

 comparable with the head plate. 



Nerve. 



Tun- | \IT Membrana Tympanal 



nel. Nuel's Deiter's basilaris. lamella. 



Vas spirale space. cells. 

 Inner Outer 



Pillar cells. 



FIG. 480. DIAGRAM OF THE STRUCTURE OF THE BASAL WALL OF THE DUCT OF THE COCHLEA. 

 A, View from the side. B, View from the surface. In the latter the free surface is in focus. It is evident 

 that the epithelium of the sulcus spiralis. lying in another plane, as well as the cells of Claudius, can 

 be seen distinctly only by lowering the tube. The membrana tectoria is not drawn. The spiral 

 nerves are indicated by dots. 



The most peripheral of the sustentacular or Deiter's cells are followed 

 by elongated columnar cells (cells of Hensen), which gradually shorten, 

 and are succeeded by the low "cells of Claudius" which extend to. the 

 limit of the membrana basilaris. In both the columnar and the low forms 

 there are single stiff filaments which are less developed than in the susten- 

 tacular cells. The centrosomes of all these cells lie near their free surfaces. 

 Beyond the basilar membrane the epithelium is continued over the 

 ligamentum spirale as a layer of cells with branching basal processes 

 extending deep into the underlying tissue. 



