XV.] SCHOUW'S HYPOTHESIS. 269 



the facts presented by existing geographical distribu- 

 tion, this hypothesis becomes highly improbable ; in 

 certain cases altogether inadmissible." All the known 

 agents of the distribution of animals and plants could 

 not account for the fact ' ' that manj^ species of plants 

 are common, on the one hand, to the Alps and the 

 Pyrenees, on the other to the Scandinavian and Scotch 

 mountains, without these species being found in the 

 plains or on the lower mountains lying between ; that 

 the flora of Iceland is almost the same as that of the 

 Scandinavian mountains ; that Europe and North 

 America have many plants in common, particularly in 

 the northern regions, which have not been transported 

 by man ; and still further difficulties, bordering on 

 impossibility, arise for such an explanation, when we 

 know that species occur in the Straits of Magellan and 

 in the Falkland Isles which belong to the flora of the 

 Arctic Pole." In order to account for these anomalous 

 distributions, he supposed that the same species may 

 originate several times, although it would appear that 

 this multiple origination is waning, from the instances 

 which he cites of the less wide and not detached distri- 

 bution of the mammals and the higher plants, which 

 are, presumably, of comparatively late creation. "Just 

 as we have seen that the leafless and flowerless plants 

 are oftener re -discovered in distant countries than 

 those bearing flowers, we may assume that the more 

 perfect animals are less prone to, perhaps never do, 

 make their appearance in several places indepen- 

 dently." Schouw supposed that creation is completed. 

 "I hold it in the highest degree probable," he writes, 

 "if not strictly proved, that no new species originate 

 at present." 



