158 



THE HUMAN BODY. 



Fig. 60. 

 PAPILLAE. 



These are called papillae, and are shown in larger size in 

 Fig. 60, in which the epidermis has 

 been stripped off, leaving only the 

 derma with the papillae on its surface. 

 In this way we sometimes scrape off 

 the epidermis by an accident, and 

 these papillae show as little red points. 

 They contain blood-vessels and 

 nerves. 



5. The palm of the hand, and especially the ends of 

 the fingers, have distinct ridges^ with furrows between 

 them, which you can easily see. 



The ridges are made by the papil- 

 lae, which are numerous in these 

 parts. When magnified, they 

 look like the figure (Fig. 61). 



6, The black spots on the 

 ridges, in the figure, indicate the 

 mouths of the sweat-ducts, which 

 are called pores. In Fig. 59 we see 

 one of these sweat-ducts. It is 

 simply a tube. As we follow it 

 down from the surface, it twists 

 in corkscrew fashion through the 

 cuticle, and then takes a wavy 



COUrse through the CUtis Vera, and PAPILLARY RIDGES IN THE SKIN 

 ,1 -, /. OP THE PALM. THE BLACK SPOTS 



terminates in the deepest part of AKE THE PoBES . 



the skin, or just beneath it, in a 



coil, which is the sweat-gland. On the outside of this coil 



is a net-work of capillary vessels (Fig. 62). From these 



capillaries some of the water and salts of the blood pass 



through into the tube. As the tube fills, its contents well 



Fig. 61. 



