284 



THE SKIN 



brane, the papillary layer, and the reticular layer of the derma, respec- 

 tively. The dermal root sheath is, however, devoid of papilla?. 



a b 



x ,^^^^^^^-, v 

 ^- 4^^^^&^^^^^^^, 



t'-^fmM'^^^-Ttr*^- - -c- -ST. . sgfe >, -\-x ^fc 



^^tt^''^^^ f ^-^C~~ v <* M <$^ '*5"TiS- : > H\ 

 ="i, vjfe.x.... > '-: ,-'-V--:/. -* -H' ?*x V;-M ,-' f A-f :: 



l^gpwS^^i^fe 





SW \ ^ i'"^^^C w ^ ' tlr / i \ .-*;' \ /* <.- n 



'is . .- 



8.' /r n'? ' VJf 



1 



^^^iflVls^v' 1 ' : '-J 



SlwWslri^' 



; 



: -.ttar.\vAV-^s 





^^ter'^r'i'-sf-r-^f^^i'^Sy^y'' '/ S^v/'/- 1 ; '/V* 





" ^^ 



v\ 5 SS?4S : .^ : : ,- ;^'-4T r ; '-^^' "-.sjSs^: 



c vr- 



tx V- -^x_y ,. "1,". ' v_ .- jm^-r-'- \ ..-. -..-~ _^^ 



V-\ , <J^'^,._ . --SSB?- "'^^rai, 



FIG. 274. TRANSECTION OF A HAIR NEAR THE MIDDLE OF THE ROOT SHEATH. 



a, dermal root sheath; 6, outer margin of the epidermal root sheath the light 

 space is the glassy membrane, the polyhedral cells form the outer root sheath; c, 

 Henle's layer of the inner root sheath; d, Huxley's layer; e, cuticle of the root sheath; 

 /, cuticle of the hair; g, cortex of the hair shaft. Highly magnified. (After Kolliker.) 



The. f/l<i*xi/ incinhraiie is a peculiarly thick homogeneous membrane 

 which is chiefly im-soblastic in origin, but whose innermost portion is 

 formed as an exoplasrnic product of the adjacent epithelium. This 



