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 ==Part II—Animals==

I. The Little Animal that Walks With its Stomach and Eats With its Feet
Don't you like the menagerie part of the circus best? And the "Zoo" in the city park? Wild animals are so strange and interesting. In every pond and creek there are animals that are just as strange. You don't have to buy a ticket to see them, as you do for a circus. But you can see a great many more of them, and all of them a great deal better, if you have a good microscope. Some of these little animals are wonderfully small, as well as wonderfully made.

The lowest forms of animal life, as of vegetable life, live in the water. The very, very smallest animal is just a single cell, too small for you to see without a magnifying glass. The yeast plant, you know, is alike all over, and gets its food by "soaking it in through its skin."

In the first figure a bit of food lies near it, in the second figure it draws near the food, next it stretches around it and then it swallows it.

The first figure shows how the amoeba changes into a solid mass if touched, and the last two figures show the amoeba dividing so as to make two. 118