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NATURK vSTUDY. 
ber-vine, as it was with all other plants, that the stem or 
vine, the leaves and the blossoms were not distinct and un¬ 
like one another, as they are now, but were similar and 
very simple. The different parts of the plant had not been 
“developed,” as the scientists say. 
Nearly all children nowadaj^s are taught something about 
plant and animal physiology, so that many of those who 
read Nature Study know that every plant and every ani¬ 
mal is built up by and composed of multitudes of minute 
bodies called cells. These cells are so small that they can 
be seen only with a powerful microscope, but they are very 
active and have a great deal to do. 
In the beginning, when plants and animals were simple 
in their structure, these cells all did the same kind of work, 
but afterwards some of them began to work all the time at 
making a particular part, as men work at different trades. 
In animals, some cells make bone, others hair, still others 
skin, and even particular parts of the skin, and so on and 
on, through every part of the body. In plants, some make 
bark, others wood or pith, and others buds. Some cells 
make the buds that grow to be branches ; others make leaf 
buds, and others the buds that grow to be flowers and 
fruit. 
As these different sets or groups of cells all work in har¬ 
mony, they build up a plant that is quite regular in a gen¬ 
eral way, with the many different parts arranged on the 
same plan in all the plants of the same kind. But the busy 
little cells have many outside things to contend with. 
Something is almost always happening to change their work 
or spoil it altogether. Perhaps, too, they have not thor¬ 
oughly learned their trades, after all the thousands of years 
they have been working at them. So no two plants, or 
blossoms, or fruits are ever exactly alike. 
At a first glance, any cucumber-vine looks much like 
any other. Its leaves grow from opposite sides of the 
