1 88 



Life and Health 



282. What gives the Skin its Color. The deeper and 

 more active layer of the epidermis, the rete mucosum, is 

 made up of pigment cells, some of which contain minute 

 granules of coloring matter that give color to the skin. 

 The differences in the tint, as brunette, fair, and blond, 

 are due mainly to the amount of coloring matter in these 

 pigment cells. In the European this amount is generally 



small, while in other peoples 

 the color cells may be brown, 

 } . ,_, ,...- yellow, or even black. 



Experiment 85. Of 

 course the living skin 

 can be examined only in 

 a general way. Stretch 

 and pull it, and notice 

 that it is elastic. Note 

 any liver spots, white 

 scars, moles, warts, etc. 

 Examine the outer skin 

 carefully with a strong magnifying glass. Study the papillae on 

 the palms. Scrape off with a blunt knife a few bits of the scarf 

 skin, and examine them with the microscope. 



283. Structure of the Hair. The hair and the nails are 

 modified forms of the epidermis. 



A hair is formed in a depression, or furrow, the inner 

 walls of which consist of the infolded outer skin. This 

 'depression takes the form of a sac and is called the hair 

 follicle, in which the roots of the hair are embedded. 



Opening into each hair follicle are usually one or more 

 sebaceous, or oil glands, producing an oily secretion which 

 serves to oil the hair and keep the skin moist and 

 pliant (Fig. 100). 



At the bottom of the follicle there is an upward projec- 

 tion of the true skin, a papilla, which contains blood vessels 



FIG. 97. Surface of the Palm of the Hand, 

 showing the Openings of the Sweat Glands 

 and the Grooves between the Papillae of 

 the Skin. 



(In the smaller figure the same epidermal surface 

 is shown as seen with the naked eye. Magni- 

 fied 4 diameters.) 



