THE NATURAL 



OF THE 



EUROPEAN 



HISTORY 



SEAS. 



CHAPTER I. 

 INTRODUCTORY. 



Every one knows that the same animals and 

 plants are not found everywhere on the surface 

 of the land, but that they are distributed so as 

 to be gathered together in distinct zoological and 

 botanical provinces, of greater or less extent, ac- 

 cording to their degree of limitation by physical 

 conditions, whether features of the earth's outline 

 or climate. Each province is not so entirely dis- 

 tinct from its neighbours as to be exclusively in- 

 habited by creatures peculiar to itself, but shares 

 more or less in the population of those regions 

 which impinge upon its boundaries; so that the 

 line between these zoological and botanical king- 

 doms, or rather republics, is not sharp and denned, 

 like that which marks the limits of political states, 



B 



