ENGLISH AND AMERICAN FLOWERS 201 



now referred to because they have been used to uphold 

 the theory that, as regards the distribution of plants, the 

 north temperate zone of the eastern and western hemi- 

 spheres cannot be separated, but must be considered to 

 form one botanical region. Recently, however. Sir Joseph 

 Hooker has stated his opinion that if we go beyond the 

 two fundamental botanical divisions — the tropical and 

 temperate floras, which, for purposes of geographical dis- 

 tribution, are of little interest, we must consider that the 

 temperate floras of the Old and New Worlds are as dis- 

 tinct as are the tropical floras of the same areas ; and he 

 adds that, although the resemblances as regards certain 

 genera and species of plants between Eastern America 

 and Eastern Asia, is very remarkable, yet the temperate 

 floras of Asia and America are in other respects totally dis- 

 similar.^ In the present chapter I shall endeavour to show, 

 in a popular manner, what is the nature and extent of 

 the dissimilarity between America and Europe as regards 

 what are commonly known as wild flowers. 



The Flowers of Europe and the Eastern States Comjmred. 



In order to restrict the inquiry within moderate limits, 

 it is proposed to consider, first and mainly, the relations 

 between the wild flowers of Great Britain as representing 

 those of Western Europe, and those of Eastern North 

 America as given in Asa Gray's Botany of the Northern 

 United States, which includes the country from New 

 England to Wisconsin, and southward to Ohio and 

 Pennsylvania. This area may be Mrly compared with 

 that of England, France, and Germany, and Avill serve as 

 a foundation for the wider comparison between North 

 America east of the Mississippi with Europe, or of the 

 whole of temperate North America with temperate Europe 

 and Asia, to which occasional reference will have to be 

 made. It must be understood that as our comparison 

 regards only the native plants of the two countries, those 

 numerous British or European species which have been 

 introduced into America by human agency and have often 



^ See Biologia Centrali-ATmricana, Botany, vol. i., pp. Ixvi — Ixvii. 



