1868.] HOOKER— ARCTIC FLORA. 327 



are Arctic European, many of which prevail throughout the polar 

 area, being distributed in the following proportions through its 

 different longitudes : — 



Arctic Europe 616 : Scandinavian forms 5S6 : 



" Asia. ....... 233 " " 1S9 



" W. America. 364 " " 254 



" E. America . 379 " " 269 



" Greenland . . 207 '* 195 



This table places in a most striking point of view the anomalous 

 condition of Greenland, which, though so favourably situated for 

 harbouring an Arctic American vegetation, and so unfavourably 

 lor an Arctic European one, presents little trace of the botanical 

 features of the great continent to which it geographically belongs, 

 and an almost absolute identity with those of Europe. Moreover, 

 the peculiarities of the Greenland flora are not confined to these ; 

 for a detailed examination shows that it differs from all other parts 

 of the arctic regions in wanting many extremely common Scan- 

 dinavian plants which advance far north in all the other polar 

 districts, and that the general poverty of its flora in species is 

 more due to an abstraction of arctic types than to a deficiency of 

 temperature. This is proved by an examination of the temperate 

 portion of the Greenland peninsula, which adds very few plants to 

 the entire flora, as compared with a similar area south of any other 

 arctic region ; and these few are chiefly arctic plants and almost 

 without exception Arctic Scandinavian species. 



There is nothing in the physical features of the arctic regions, 

 their oceanic or aerial currents, their geographical relations, nor 

 their temperature, which, in my opinion, at all accounts for the 

 exceptional character of the Greenland flora ; nor do I see how it 

 can be explained, except by assuming that extensive changes of 

 climate, and of land and sea, have exerted great influence, first, in 

 directing the migration of the Scandinavian species over the whole 

 polar zone, and afterwards in introducing the Asiatic and American 

 species with which the Scandinavian are so largely associated in 

 all the arctic districts except those of Europe and Greenland. It 

 is inconceivable to me that, under existing conditions of sea, 

 land, and temperature, so many Scandinavian plants should 

 have found their way westward to Greenland, by migration 

 across the Atlantic, and stopped short on its west coast, net 

 crossing to America ; — or that so many American types should 

 terminate as abruptly on the west coast of Baffin's Bay, and not 



