146 THE AUDITORY NERVE AND COCHLEA, BY W. WALDEYER. 



sioned in part by the easily separable nature of the several 

 structures, and especially by the peculiar mode of junction of 

 the two chief types of tissue of the cochlea, the connective 

 tissue and the epithelium ; for these are here interwoven with 

 each other in a manner not elsewhere seen in the body. 



In axial vertical sections, as in figs. 321 and 322, the crista 

 appears in the form of a hook-like thickening superimposed upon 

 the vestibular side of the lamina spiralis ossea. It is not 

 sharply differentiated from the bony tissue, since the stellate 

 corpuscles of the latter recur in the matrix of the crista, and 

 vascular loops also enter its substance. In some instances, 

 irregularly formed lamellae of calcareous salts are deposited in 

 it, and in the Bats a tolerably regular kind of ossification 

 occurs. The net of the matrix is either composed of stiff 

 fibres, or is of a more homogeneous nature, and behaves like 

 dense connective tissue to reagents. I think, therefore, that it 

 may be most correctly regarded as an osteogenous substance 

 (in the sense of the term used by Miiller and Virchow) deve- 

 loped in continuity with the vestibular periosteum of the 

 lamina spiralis ossea. It may here be provisionally stated 

 that the crista becomes of a somewhat deeper colour than 

 the subjacent bone in perosmic acid and in chloride of pal- 

 ladium. 



If the crista be examined from the vestibular surface (figs. 

 324, 325), the projecting border, in consequence of the presence 

 of deep indentations, appears to be broken up into separate 

 segments of nearly equal size, and of elongated quadrangular 

 form, the auditory teeth of Huschke (28), which really resemble 

 a row of incisor teeth seen from the anterior surface. Inter- 

 nally, these teeth are prolonged into a number of rounded or 

 elongated, often peculiarly lustrous or highly refracting struc- 

 tures (fig. 325, d), which are nothing else than the processes of 

 the osteogenous substance of the crista. The furrows between 

 these, as well as the furrows between the auditory teeth, 

 are filled with small roundish angular cells, which clearly 

 belong to the epithelium of the ductus cochlearis, as Kblliker 

 (30), for a part of it at least, maintains. These cells are con- 

 tinued externally, by means of the interdental furrows, directly 

 into the epithelium of the sulcus spiralis internus (fig. 324), 



