342 



THE 



under surface on the front part of the matrix, which is here 

 called the bed of the nail. This part of the matrix is not uni- 



FIG. 117. 



FIG. 118. 



a be 



FIG. 117. Medium-sized hair in its follicle, magnified 50 diameters (from Kolli- 

 ker). a, stem cut short ; b, root ; c, knob ; d, hair cuticle ; e, internal, and/, external 

 root-sheath ; g, h, dermic coat of follicle ; i, papilla ; k, k, ducts of sebaceous glands ; 

 I, corium ; m, mucous layer of epidermis ; o, upper limit of internal root-sheath (from 

 Kolliker). 



FIG. 118 Magnified view of the root of a hair (after Kohlrausch). a, stem or 

 shaft of hair cut across ; 6, inner, and c, outer layer of the epidermal lining of the 

 hair-follicle, called also the inner and outer root-sheath ; d, dermal or external coat 

 of the hair-follicle, shown in part; e, imbricated scales about to form a cortical layer 

 on the surface of the hair. The adjacent cuticle of the root-sheath is not repre- 

 sented, and the papilla is hidden in the lower part of the knob where that is rep- 

 resented lighter. 



formly smooth on the surface, but is raised in the form of lon- 

 gitudinal and nearly parallel ridges or laminae, on which are 



