ENVIRONMENT 87 



multiplies and prospers to the extent that it 

 covers whole hillsides of snow like a blanket 

 covers them so completely that the reddish color 

 of the plant, imparted to the snow, first gave rise 

 to the tales of far northern travelers as to the 

 color of the snowfall and explained the apparent 

 phenomenon of red snow. 



Another division of this family, at the oppo- 

 site extreme, thrives in the waters of Arrow- 

 head Sulphur Springs in California lives its 

 life and reproduces itself in water so hot that 

 eggs may be easily cooked in it. 



In addition to these microscopic members, one 

 thriving on the Arctic snows, the other in 

 water at nearly the boiling point, there is still 

 another member of this family which has formed 

 the largest plant colony in the world. This, the 

 gigantic growth of the Sargasso Sea, consists of 

 a small seaweed wrenched from the coast and 

 forms a huge tangled, floating mass. 



And so on; some of this family of the algae 

 grow on and in animals, some on other plants, 

 some on iron, some on dry rocks, some in fresh 

 water, and some in the salt seas. 



The monkey-puzzle trees, Araucarias, show 

 an adaptability to environment as striking as 

 that of the cactus although for a wholly dif- 

 ferent purpose. 



