ANIMAL LIFE IN THE WOODS 173 



All squirrels are exceedingly well adapted to arboreal life. 

 Their bodies are light, the legs short and all the toes are 

 provided with sharp claws, by which they can hold to the 

 bark of trees and even run along small horizontal branches. 



Their teeth also are well fitted to open and to grind up hard 

 seeds. They have two upper and two lower chisel-like 

 incisors. As you see on this skull, there is a gap behind 

 the incisors in each jaw, and behind the gap we see a num- 

 ber of molars. With their sharp incisors, they can chisel 

 open the hardest nuts and gnaw holes through boards. 

 Their food is ground between the molars by a forward and 

 backward motion of the lower jaw. Do you think they 

 could gnaw by moving the jaws sideways as a cow moves 

 them ? And 1 have another hard question for you. All 

 boys know that a knife blade becomes narrower by the wear- 

 ing away of the steel, if you keep it long enough and use it 

 much. The teeth of horses and also human teeth wear off 

 with age. While the squirrel is awake, it scarcely passes 

 an hour without gnawing on some hard substance. How is 

 it that its teeth do not wear off ? The fact is, they do wear 

 off quite fast; but they keep on growing just as fast. If you 

 ever keep a squirrel for a pet, you must give it nuts and 

 hard seeds and even pieces of wood, on which it can use its- 

 teeth ; for without such exercise these soon become so long 

 that they hinder the animal in eating. Squirrels not only 

 can gnaw, but they must gnaw. 



I am sure we all enjoy the quick graceful motions of the 

 squirrels and love to have the stillness of the summer woods 

 broken by their lively scolding. Who would not rather 

 observe a live squirrel among the shady boughs, than shoot 

 it and see it lying on the ground dead and bleeding ? All 

 lovers of nature certainly regret that, on account of their 

 "bird and grain eating propensities, they are not desirable in 

 the immediate neighborhood of our homes. Young squirrels 



