A SHEAF OF NATURE NOTES 



this or that. Nature aims to fill the world with her 

 progeny. Only power to win in the competition of 

 life counts with her. As I have so often said, she 

 plays one hand against the other. The stakes are 

 hers whichever wins. Wheat and tares are all one 

 to her. She pits one species of plant or animal 

 against another — heads I win, tails you lose. Some 

 plants spread both by seed and runners, this 

 doubles their chances; they are kept in check 

 because certain localities are unfavorable to them. 

 I know a section of the country where a species 

 of mint has completely usurped the pastures. It 

 makes good bee pasturage, but poor cattle pas- 

 turage. Quack grass will run out other grass 

 because it travels under ground in the root as well 

 as above ground in the seed. 



XI. NATURAL SCULPTURE 



We may say that all the forms in the non-li\ang 

 world come by chance, or by the action of the un- 

 directed irrational physical forces, mechanical or 

 mechanico-chemical. There are not two kinds of 

 forces shaping the earth's surface, but the same 

 forces are doing two kinds of work, piling up and 

 ' pulling down — aggregating and accumulating, and 

 separating and disintegrating. 



It is to me an interesting fact that the striking 

 and beautiful forms in inorganic nature are not as 

 a rule the result of a building-up process, but of a 



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