This section is from the "The New Student's Reference Work Volume 5: How And Why Stories" by Elinor Atkinson.
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, ! 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."
An Amoeba Feeding
In first figure a bit of food lies near it, in 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.
One of these single-celled animals is called the amoeba. That is a Greek word that means "change." The amoeba can change its shape whenever it wants to. If you could put on a pair of wings as easily as the amoeba can make feet, you could do what every boy has wanted to do—fly like a bird. Whenever the amoeba wants to move in a certain direction, little legs push out from that side of its body and draw the rest of the amoeba after it. Whenever it wants to go in another direction it draws in these legs and makes legs on the other side.
But when it wants to eat it doesn't make a mouth, and put food in this mouth, as you might suppose. Whenever it touches the food on which it lives, it simply wraps itself around it like a little boy trying to carry a big watermelon.
It looked very odd to see the hair-like growths of the flower cup close around the bee and make it give up as much of the pollen on its legs as the plant wants, before letting go. It looked as if even flowers could think sometimes, So the little amoeba acts as if it could think, too. It seems to have ideas and tastes just as we have. Not so many ideas, and not so many tastes; but you would hardly expect that of an amoeba, would you? An amoeba is thousands and thousands of times smaller than we are—hardly a hundredth of an inch across its little body. Just think what might happen, if we were as many times brighter than an amoeba as we are times larger !
For see what it does :
If it wraps itself around a piece of food that is too big for it— if it "finds its eyes are bigger than its stomach" as little boys do sometimes—it just unwraps itself from the food and glides away. Sometimes it seems not to like the taste of things, for, having wrapped itself around something, it holds it awhile and then lets go of it again without eating it. Some of the little animals it eats have shells. When it is through with one of these it unwraps itself and drops the shell.
And it seems to have nerves, too. Of course we can't tickle its feet because it hasn't any except those that it makes when it wants to go walking. But if you touch it, or shake it, it pulls all of itself in, making itself into a little round drop of jelly. You have often noticed how an earth-worm, or lishing-worm, as you call it, will shrink when you touch it. This shows that the earth-worm has "feelings," too. It has something that answers for nerves. We couldn't get along very well without nerves because it is through them that we know what is going on around us. Nerves are just as necessary to make things go right inside of us. It is by means of the nerves of the eye that we see, the nerves of the ear that we hear, the nerves of the tongue that we taste.