10/16 Both the hair and the nails are really parts of the outer skin, which is curiously changed and hardened. The nails lie upon the surface of the true skin and grow from the under side as well as from the little fold of skin at the root of the nail. They are made to give firmness and protection to the ends of the fingers and toes. The nails of the fingers are also useful in picking up small objects and in many other ways. Uses of the Skin.~--The skin is useful in several ways: (1) _It Removes Waste._--The sweat glands and ducts are constantly at work removing from the blood particles which have been worn out and can be of no further use. |