



FIG. 271. FIVE STAGES IN THE DEVELOPMENT OF A HUMAN HAIR. 

 a, papilla; b, arrector pili; c, the line is directed toward the primordial shaft; 

 d, cells which form the hair canal; e, sebaceous gland; /, hair germ in epidermis; 

 g, hair shaft; h, Henle's layer; i, Huxley's layer; k, cuticle of the root sheath; I, 

 inner root sheath; m, outer root sheath in tangential section; n, outer root sheath 

 in longitudinal section; o, dermal root sheath; P, epithelial bed. X 460. (After 



