44 WONDERS OF THE TROPICAL FORESTS. 
figuring along with the primitive vegetatiuii of the 
land. 
Although chiefly tropical, the cactuses have a perpen- 
dicular range, which but few other families enjoy. Frura 
the low sand-coasts of Peru and Bolivia they ascend throuirh 
vales and ravines to the highest ridges of the Andes. 
Magnificent dark-brown Peireskias (the only cactus genus 
bearing leaves instead of prickles) bloom on the banks of 
the Lake of Titicaca, 12,700 feet above the level of the sea ; 
and in the bleak Puna, even at the very limits of vegeta- 
tion, the traveller is astonished at meeting with low bushes 
of cactuses thickly beset with yellow prickles. 
What a contrast between these deformities and the 
delicately feathered mimosas, unrivalled among the loveliest 
children ofFlom in the matchless elegance of their foliage! 
Oar common acacias give but 
a faint idea of the beauty 
which these plants attain 
under the fostering rays of 
a tropical sun. In most 
species the branches extend 
horizontally, or umbrella- 
shaped, somewhat like those 
of the Italian pine, and the 
deep-blue sky shining through 
the liglit green foliage, whose 
delicacy rivals the finest em- 
broiderj', has an extremely picturesque effect. Endowed 
with a wonderful sensibility, many of the mimosas seem, 
as it were, to have outstepped tlie bounds of vegetable lif«.\ 
and to rival in acuteness of feeling the coral polyps ami 
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 con- 
traction of the small gi-ey-green leaflets spreads in quiver- 
ing circles over the licld, making one almost believe, 
