i] HISTORICAL 7 



Meanwhile in 1859 Darwin's Origin of Species 

 had given a great impetus to the study of geographi- 

 cal distribution and caused a parting of the ways in 

 its treatment, especially in the mapping of the world 

 into regions or other divisions. Whilst some writers 

 were, and are, satisfied to express by their realms, 

 regions, or zones the recent, actually existing, sta- 

 tistic similarities and differences of the faunas of the 

 various countries, other workers, more appreciative 

 of evolution, tried to apply genetic principles to the 

 selection of their divisions, which they rightly con- 

 sidered as original centres of creation and subsequent 

 dispersal. 



Haeckel, the foremost apostle of ' Darwinism ' in 

 Germany, has given us in his Generelle Morphologie, 

 1866, the terms Oecology, the relation of organisms 

 to their environment, and Chorology, their distri- 

 bution in space. The 14th chapter of his History 

 of Creation, 1868, is devoted to the distribution of 

 organisms, with the emphatic assertion that ' not 

 until Darwin can chorology be spoken of as a 

 separate science, since he supplied the acting causes 

 for the elucidation of the hitherto accumulated mass 

 of facts.' 



One of the earliest writers to grasp the new 

 situation was Pucheran 1 in France. He pleaded that 



1 Pucheran had already, in 1865, insisted upon the essential unity 

 of the faunas of Europe, Asia and Africa, and on the necessity of 



