ACTION OF THE TECTORIAL MEMBRANE 



483 



Fig. 3 Piece from the 5th half turxi of a teased out tectorial membrane of the 

 pig viewed from its apical surface. Given to show more nearly the actual ap- 

 pearance of the membrane as seen over a black surface and to show the course of 

 its fibrils embedded in the matrix. The right hand side of the figure represents 

 the appearance presented where the membrane had been torn across in teasing. 

 The cut surface shown in the left side was not drawn from this specimen but added 

 onto the figure as suggested in the vertical sections of this turn of the coil. The 

 bottom part of the figure represents the attached axial zone of the membrane. 

 The line showing through the outspanning zone is 'Hensen's sti'ipe.' 



and its specific gravity appears practically the same as that of 

 the endolyraph in which it lies. Its fibrils are not arranged in it 

 transversely but course in it obliquely, their direction inclined 

 toward the apical end. Those in its apical side are more inclined 

 toward its apical end than those in its basal side, thus inter- 

 crossing in the structure of the membrane rendering it less 

 fragile for, in teasing it out even after fixation, it never breaks 

 transversely but always tears apart (fig. 3). In its natural 



