FOEEIGN PLANTS, HOW nTTEODUCED. 67 



In most of the Southern countries of Europe, the sheep and 

 horned cattle winter on the plains, but in the summer are driven, 

 sometimes many days' journey, to mountain pastures. Their 

 coats and fleeces transport seeds in both directions. Hence we 

 see Alpine plants in champaign districts, the plants of the plains 

 on the borders of the glaciers, though in neither case do these 

 vegetables ripen their seeds and propagate themselves. This ex- 

 plains the occurrence of tufts of common red clover with paUid 

 and sickly flowers, on the flanks of the Alps at heights exceeding 

 seven thousand feet. 



The hortus siccus of a botanist may accidentally sow seeds from 

 the foot of the Himalayas on the plains that skirt the Alps ; and 

 it is a fact of very familiar observation, that exotics, transplanted 

 to foreign chmates suited to their growth, often escape from the 

 flower garden and naturahze themselves among the spontaneous 

 vegetation of the pastures. When the cases containing the artistic 

 treasures of Thorvaldsen were opened in the court of the museum 

 where they are deposited, the straw and grass employed in pack- 

 ing them were scattered upon the ground, and the next season 

 there sprang up from the seeds no less than twenty-five species 

 of plants belonging to the Roman campagna, some of which 

 were preserved and cultivated as a new tribute to the memory 

 of the great Scandinavian sculptor, and at least four are 

 said to have spontaneously naturalized themselves about Copen- 

 hagen.* The Turkish armies, in their incursions into Em*ope, 

 brought Eastern vegetables in their train, and left the seeds of 

 Oriental wall-plants to grow upon the ramparts of Buda and 

 Vienna.f In the campaign of 1814, the Russian troops brought, 

 in the stufl&ng of their saddles and by other accidental means, 

 seeds from the banks of the Dnieper to the vaUey of the Rhine, 

 and even introduced the plants of the steppes into the environs of 

 Paris. 



produce seed in those regions. This is a fortunate circumstance, for other- 

 >vise this most worthless and least ornamental of trees would spread with a 

 rapidity that would make it an annoyance to the agriculturist, 



* Vaupell, Bbgens Indvandring i de Danske Skove, p. 2. 



f I believe it is certain that the Turks introduced tobacco into Hungary, and 

 probable that they in some measure compensated the injury by introducing 

 maize also, which, as well as tobacco, has been claimed as Hungarian by 

 patriotic Magyars. 



