CHAPTEE XVI 



GEOGRAPHICAL DISTRIBUTION OP ANIMALS 



148. Geographical distribution. Under the head of dis- 

 tribution we consider the facts of the diffusion of organ- 

 isms over the surface of the earth, and the laws by which 

 this diffusion is governed. 



The geographical distribution of animals is often known 

 as zoogeography. In physical geography we may prepare 

 maps of the earth which shall bring into prominence the 

 physical features of its surface. Such maps would show 

 here a sea, here a plateau, here a range of mountains, 

 there a desert, a prairie, a peninsula, or an island. In po- 

 litical geography the maps show the physical features of 

 the earth, as related to the states or powers which claim 

 the allegiance of the people. In zoogeography the realms 

 of the earth are considered in relation to the types or 

 species of animals which inhabit them. Thus a series of 

 maps of the United States could be drawn which would 

 show the gradual disappearance of the buffalo before the 

 attacks of man. Another might be drawn which would 

 show the present or past distribution of the polar bear, 

 black bear, and grizzly. Still another might show the 

 original range of the wild hares or rabbits of the United 

 States, the white rabbit of the Xortheast, the cotton-tail of 

 the East and South, the jack-rabbit of the plains, the snow- 

 shoe rabbit of the Columbia Eiver, the tall jack-rabbit of 

 California, the black rabbits of the islands of Lower Cali- 

 fonia, and the marsh-hare of the South and the water-hare 

 of the canebrakes, and that of all their relatives. Such a 

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