Pond Life 
world as we know it. Then we find 
a few shells, and, later, some of the early 
forms of fish. 
Then plants began to abound. These 
plants, though very large, possessed no 
flowers, but must have been in exceeding 
abundance, for to them we owe the 
deposits of coal which now we burn, and 
so utilize the heat and energy stored up 
by them from the heat of the sun, so 
many thousands and thousands of years 
ago. _ Plants jare, “after yall, of Mle 
greatest importance to the world gener- 
ally, for on them everything else 
depends. Every creature lives on 
plants, either directly by eating them, 
or indirectly by eating some other 
animal which eats them. If you don't 
eat grass directly, you do so indirectly 
every time you eat a mutton chop, for 
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