492 THE UNIVERSE. 



go back to the times of the cataclysms which laid them 

 bare ! 



But it is particularly in the dicotyledonous plants that 

 longevity is so extraordinary. Some of these grow so slowly 

 that ages seem scarcely to alter their dimensions. 



If we look at vegetable life scattering its great families 

 over the globe, we everywhere find the same contrasts, 

 misery by the side of grandeur. The bare rock which raises 

 its shattered masses on the mountain slope is only colored 

 with a crust of lichens and mosses, which dot its surface like 

 so many pencil marks. Below these regions, where the se- 

 verity of the air destroys everything, we find pines and oaks 

 twisted and dwarfed, while lower down rise magnificent and 

 sombre forests of Coniferse, encircling the mountains with 

 their girdle of black. 



The palms compose numerous groups in all the equatorial 

 regions. But vegetable life reveals itself peculiarly with all 

 its variety and splendor in the immense virgin forests of 

 the tropics, where the axe has never yet shorn it of its 

 exuberance. Some present such a profusion of aged trees 

 entwined with ferns and creepers that they are absolutely 

 impenetrable, unless some stream of water happen, in its 

 winding course, to furnish the daring traveller with a nat- 

 ural path. 



The special character of the vegetation in some of these 

 forests gives them quite a characteristic aspect. When the 

 parasitic orchises predominate, they form on every side ele- 

 gant chandeliers, as it were, of verdure and flowers ; or 

 they hang here and there in long slender pendants, looking 

 at a distance like so many gigantic spiders, displaying their 



