OBSERVATIONS ON FLORAL CHANGES. 81 



though they come to us like shipwrecked marinei-s of another country, who 

 could feel in his heart to cast them out? If we lay hold of them, it is not 

 to treat them roughly, as intrusive aliens, but to give them a kindly welcome 

 as interesting strangers. We treat them in the same manner as our ornitho- 

 logists treat a rare and beautiful straggler, which in some of its long migratory 

 flights, has been driven by stress of weather, to make our isle a temporary 

 resting-place." Although strongly inclined to subscribe to this generous apology 

 on behalf of Sargassum, we certainly do not adopt such a view in regard to 

 the land plants more especially under consideration, for while the Sargassum 

 is only floated to our shores by accidental circumstances, the land plants 

 have in reality taken up their abode with us, and are permanently naturalized. 



It is not in Britain alone, that the influences of the human family in 

 modifying the character of vegetation are observable. History traces the 

 introduction to the Indian Peninsula, and indeed to many of the British 

 colonies, of many plants which cannot be considered true natives, although now , 

 abundantly diffused, and ministering to the wants of mankind. The Creator 

 has assigned to every species certain powers of diff"usion, whereb}^ it is enabled 

 to resist the climatic conditions of the lands which it is destined to adorn, 

 with its beauty; and to whose animal inhabitants it affords a suitable food. 



We find nothing superfluoas in nature, and we cannot well conceive, how 

 to certain plants, more than others, has been given the capability of enduring 

 great extremes of heat and cold, drought and humidity, if we are not io 

 suppose that such plants were originally intended to become diffused throughout 

 the world, to a corresponding extent. The ingenuity of man often carries the 

 fruits and flowers of the tropics to inhospitable regions, and by imitating the 

 natural conditions under which they flourish in their native localities, is enabled 

 to develop them successfully, and to reap the benefits of his industry; but no. 

 sooner does his nursing hand leave them, than they disappear. Not so with 

 the plants to which we have called attention. They may, in many cases,. 

 have been originally introduced, through the instrumentality of mankind, to 

 a country or district, (and we know many that have been,) but once intro- 

 duced, and finding the climatic and physical conditions which are favourable 

 for their growth, they have taken firm hold of the soil; and not only do 

 not depend upon man's aid, for their continued existence in their new habitats, 

 but, in numerous instances, bid defiance to his strenuous efforts to extirpate 

 them. 



I may, on some future occasion, trouble the Society with a continuation of 

 my remarks on this subject, and shall then exhibit a series of specimens in 

 illustration. 



VOL. 1. 



