THE SKIN, ITS APPENDAGES AND ITS FUNCTION. 41 



another. The horny epithelial cells that go to form 

 the hair contain the pigment that gives it its color. 

 Like the hairs, the sebaceous glands are situated in all 

 parts of the body except the palms of the hands and the 

 soles of the feet. They lie in the papillary layer and 



FIG. 12. Skin and longitudinal section of hair: a, Epidermis; b, corium; c, 

 sebaceous gland; d, fibrous root-sheath; e, glassy membrane;/, outer root-sheath; 

 g, inner root-sheath; h, expanded bulbous end of hair; i, papilla of hair; ;', 

 arrector pili; k, adipose tissue. (Leroy) 



empty into the hair follicles, except occasionally, when 

 they empty directly upon the surface of the skin. They 

 secrete an oily substance, sebum, the debris resulting 

 from the degeneration of the epithelial cells of the 

 gland itself, which serves to keep the hair glossy and 

 the skin soft and flexible. 



