54 LEAVES FROM THE BOOK OF NATURE. 



dispersion of the deadly night-shade. It came at first 

 from India, whence gipsies carried it over the wide world, 

 making constant use of its medicinal virtues and vices. 

 They always kept it on hand, and even raised it around 

 their encampments, and thus it followed their trace from 

 the far east to the far west. 



One peculiar effect of this migration in masses is, that 

 certain plants, first introduced by man, have subsequently 

 become so generally diffused, independent of his agency, 

 as to displace, in some instances, the whole original flora 

 of a country. The rich pampas of South America have 

 thus been overrun with the artichoke and peach-tree of 

 another continent; immense tracts are now covered with 

 these intruders from abroad, and rendered useless as pas- 

 tures. Even islands have not escaped this fate. In St. 

 Helena, original plants have almost entirely disappeared, 

 and made room for those which have been brought there 

 from Europe and Asia. In eastern China the population 

 is so dense, and the culture of the soil so high, that, 

 with the exception of a few water-plants in skilfully- 

 flooded rice-fields, all the plants which originally grew 

 wild .there, have been driven out. The whole land is now 

 exclusively covered with grains raised by the hand of 

 man, and the botanist finds, in the lowlands at least, not 

 a single plant which is not artificially cultivated. 



Some plants thus literally conquer a country and banish 

 the native inhabitants ; others disappear, not before ene- 

 mies of their own race, but emigrate because of climatic 

 changes. " Palestine, which was once a land flowing with 

 milk and honey. Where the grape and the date abounded, 



