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THE WORLD OF ANIMAL LIFE 



RODENTS 



This is a very large group of animals. So large is it, indeed, 

 that about one-third of all the mammals in the world belong to it. 

 The name " Rodent " is given to the class because they all nibble 



or gnaw their food instead of 

 biting it. 



A Rodent animal may 



always be known by its front 



teeth. If we look at a hare, a 



rabbit, a rat, or a mouse, for 



example, we shall see that the 



front teeth are very much 



longer than the rest, and that 



they project quite out of the 



mouth. As the constant gnawing wears them away, they are 



continually growing again, so that they are always kept at just the 



right length. 



These teeth are specially formed for nibbling hard sub- 

 stances. They are faced with a thin plate of extremely hard 

 enamel, which is not worn away so rapidly as the softer bone 

 behind it, and thus a sharp cutting edge is always preserved. 



Skull of Rodent, or Gnawing 



Natural Size) 



Animal (Rat) 



THE SQUIRREL 



No one who has seen it can help admiring the Squirrel — that 

 pretty, graceful little animal, with a big bushy tail, -which runs 

 so quickly up the trees, and scampers so nimbly along the 

 branches. 



In almost any wood it may be seen at play, skipping about 

 among the dead leaves upon the ground, or gaily chasing and 

 gambolling with its companions. Up one tree it goes, along a 

 branch, and down another, seeming to be as merry as the day 

 is long. 



But one must stand quite still while watching it; for the slightest 



