30 THE EVOLUTION OF PLANTS 



custom has seized on an essential distinction, 

 for, so far as Gymnosperms now living are con- 

 cerned, their cones have not much in common 

 with true flowers, and the two classes are wide 

 as the poles asunder, though still confused in 

 many old-fashioned botany books. 



The dominance of the Angiosperms in the 

 Flora of the modern world is shown not only 

 by the mere number of species, but still more 

 by the importance of the part they play. As 

 forest trees some Conifers can compete with 

 them; occasionally Bracken-fern or Bog-moss 

 may prevail over considerable areas; other- 

 wise it is the Angiosperms which cover the face 

 of the earth with vegetation. They have adapted 

 themselves to every climate, from the High 

 Alps, where Ranunculus glacialis grows at a 

 height of over 14,000 feet in the Bernese Ober- 

 land, surrounded by perpetual snow, to the hot 

 deserts of Central Africa or America, where 

 gigantic Euphorbias and Cacti flourish in a 

 rainless wilderness. 



The Angiosperms, besides covering the surface 

 of the earth with forests, prairies and meadows, 

 have fitted themselves to every niche where 

 plant-growth is possible. 



In the tropics and in damp forests elsewhere, 

 hundreds of species grow as epiphytes on trees 

 and shrubs. Most of the showy Orchids in hot- 



