INTRODUCTORY EXPLANATIONS. 



Nature makes plants more or less dissimilai- in their 

 forms and other physical characters ; and upon the de- 

 grees of resemblance which he can trace in those charac- 

 ters, Man founds his technical aiTangement of their names 

 and descriptions in books. The actual gioupings of plants, 

 seen in the wilds of nature, are totally different fiom those 

 invented by botanists for the convenience of systematic 

 arrangement. Species which are widely dissimilar in their 

 physical chai'acters, so far from being widely sundered in 

 natui'e, are frequently found growing in the most neigh- 

 bourly proximity ; while other species, which are so similar 

 that they can scarcely be distinguished by any written cha- 

 racters, may have their geographical position in countries 

 the most remote, or in soils the most different. 



The botanist who looks with an observant eye to the 

 floral productions of the earth, as a whole, or to those of 

 any considerable section of its sm-face, may soon discover 

 almost as much of variety in the distribution of the plants, 

 as is seen among those physical characters of shape or 

 structure, in accordance with which they are technically 

 classified in books. 



Hence arises the study of Geographical Botany, or in- 

 vestigations into the distribution of plants over the surface 



7. 



