528 THE UNIVERSE. 



thus plant the tree on the crumbling porticoes of our castles 

 and our old ruined churches. The grape of America (Phy- 

 tolacca decandra), recently introduced near Bordeaux, has 

 been disseminated by the winged songsters of our forests 

 all through southern France, and even as far as the desert 

 gorges of the Pyrenees. It is to the magpie of Ceylon that 

 the propagation of the cinnamon-trees in that island is often 

 intrusted, and this fact is so generally known that the in- 

 habitants afford it ample protection. 



Certain islands, which everything proves were formed 

 after the great continents near them, owe the principal ele- 

 ments of their colonization solely to birds and to the marine 

 currents. This is particularly the case with Iceland, which 

 has been observed to be furnished with plants brought to it 

 from Greenland and Northern Europe, carried thither by 

 the innumerable birds which annually migrate in these 

 latitudes. 



It is also to birds that the varied flora seen in the interior 

 of the Coliseum at Rome is owing. In fact, the entire veg- 

 etation which covers these celebrated ruins, from the fig- 

 trees, the powerful roots of which split its arches, to the 

 humble grass that blooms upon its fallen stones, has been 

 introduced into the vast structure solely by means of ani- 

 mals. 1 



In like manner, some mammals, even of the most car- 

 nivorous kind, eat sundry fruits of which their digestive 

 organs, though possessed of great energy, only act on the 



1 According to Sebastiani, an Italian author, the number of species of plants 

 growing in the Coliseum of Rome which have been transported thither by the 

 birds is not less than 261. 



