THE SENSITIVE PLANT. 135 



the branches extend horizontally, or umbrella-shaped, somewhat 



like those of the Italian pine, and the deep-blue sky shining 



through the light green foliage, 



whose delicacy rivals the finest 



embroidery, has an extremely 



picturesque effect. Endowed with 



a wonderful sensibility, many of 



the mimosas seem, as it were, 'to 



have outstepped the bounds of 



vegetable life, and to rival in 



acuteness of feeling tlie coral 



polyps and the sea anemones of 



the submarine gardens. 



Large tracts of country in Brazil are almost entirely covered 

 with sensitive plants. The tramp of a horse sets the nearest 

 ones in motion, and, as if by magic, the contraction of the 

 small grey-green leaflets spreads in quivering circles over the 

 field, making one almost believe, with Darwin and Dutrochet, 

 that plants have feeling, or tempting one to exclaim with 

 Wordsworth — 



* It is my faith, that every flower 

 Enjoys the air it breathes.' 



Among the most remarkable forms of tropical vegetation, the 

 creeping plants, bush-ropes, or lianas (cissus, bauhinia, bignonia, 

 banisteria, passiflora), that contribute so largely to the impene- 

 trability of the forests, hold a conspicuous rank. Often three 

 or four bush-ropes, like strands in a cable, join tree to tree, and 

 branch to branch ; others, descending from on high, take root 

 as soon as their extremity touches the ground, and appear like 

 shrouds and stays supporting the mainmast of a line-of-battle 

 ship ; while others send out parallel, oblique, horizontal, and 

 perpendicular shoots in all directions. 



No European is able to penetrate the intricate network of a 

 forest thus matted together : astonished and despairing, he 

 stands before the dense cordage that impedes his path, and, 

 should he attempt to force his way through the maze, the- 

 strong thorns and hooks with which the tropical creepers are 

 generally armed would soon make him repent of his bold- 

 ness. The Brazilian planter never thinks of entering the 

 forest without a large knife, or without being accompanied 



