140 



HUMAN BIOLOGY 



+ derma = skin), and an inner, the der'mis (Fig. 43). When one 

 gets a blister by burning the skin, most of the epidermis is lifted up 

 by an excessive amount of watery fluid that comes from the blood. 

 In a blister one can easily distinguish the white epidermis from the 

 pink layers of the dermis lying beneath. 



201. Glands of the skin. — Two kinds of glands are found in the 

 skin; namely, the oil glands and the sweat or per-spi'rchto-ry glands. 



^epidermis 



dermis 



pai 

 dermis 



oil glan 



hair follici 





sweat gland 



'fatty tissue 



Fig. 43.- 



papilla of hair 

 - Vertical section of scalp, highly magnified. 



The former are found in most parts of the skin, being most numer- 

 ous in the scalp and in the skin of the face. Like hairs, however, 

 oil glands are wanting on the palms of the hands and the soles of the 

 feet. Sweat glands, on the other hand, are most numerous in the 

 regions just named. One writer estimates that there are 2800 sweat 



