So THE SCIENTIFIC EVIDENCES OF 



each continent, also, we see the same fact ; for 

 on the opposite sides of lofty and continuous 

 mountain ranges, of great deserts, and even of 

 large rivers, we find different productions ; though 

 as mountain chains, deserts, &c, are not so im- 

 passable, or likely to have endured so long as 

 the ocean-separated continents, the differences 

 are very inferior in degree to those characteristic 

 of distinct continents." That is to say, the 

 differences are usually confined to species and 

 genera, whereas in the case of continents the 

 differences extend to orders. Similarly in marine 

 productions the same laws prevail — the species 

 on the different sides of the American continent, 

 for instance, being very distinct. Now, this law 

 cannot be explained by any reasonable argument 

 from design. 



And still stronger does the present argument 

 become when we look to the fossil species contained 

 on different continents ; for these fossil species 



