PART I 

 THE BIRDS 



CHAPTER I 

 BIRDS AND BIRD LIFE 



The term "birds" is used to define a group of animals 

 which are feathered, and warm blooded, and produce eggs. 

 This class includes all kinds of feathered animals, whether 

 they live on land, water or trees. Throughout the world 

 are hundreds of different kinds of birds, representing numer- 

 ous distinct types, and many of these are useful to man. 



Birds and Their Relation to Animal Life. — All animals 

 existing on the earth are classified under the general term, 

 "Animal Kingdom." This great kingdom is divided and 

 subdivided until we come to a class or group known as 

 aves or birds. Animals which belong to this class are known 

 as true birds. They are all feathered and have four clearly 

 defined limbs. The hind pair are the legs, which are used 

 for walking on the ground, or for swimming in the water. 

 The front pair of limbs are usually called wings, and are 

 designed for flight. Birds have no teeth. They have a 

 heart similar to other animals, and the blood circulates the 

 same as in man. Their lungs are very highly developed. 

 The class aves or birds is subdivided into three groups, 

 which will later be described. Birds are one of the most 

 highly specialized classes of the animal kingdom. They 

 differ from other common animals in their ability to fly and 

 in the fact that they are covered with feathers. 



Aves or Birds. — The class aves or birds includes a great 

 variety of types; among them are the eagle, the ostrich, the 

 humming bird, and the duck. They not only differ in size, 

 but vary greatly in habit and mode of life. In structure, 

 birds closely resemble snakes and reptiles. Since birds are 



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