teacup turned upside down. It keeps to this shape until the food is digested. The anemone's stomach is in the center of its body, but it seems to take the whole inside of the anemone to digest its food, just as it does with the little amoeba.
The anemone's stomach is one of the queerest things you ever saw. It is surrounded by little rooms that are connected with each other by two openings that we might call "windows." Each of these rooms is also connected with the stomach in the middle, and with those parts which, as you see, look like the petals of a flower, when the anemone is spread out, waiting for its food. Each of these "petals" is hollow like the fingers of a glove. The anemone not only lives surrounded by water on the outside, but it is full of water on the inside. Water is to the anemone what blood is to you; it circulates all through the anemone, and the anemone makes its petal-like fingers stand up by filling them with water. These fingers are called tentacles. When the little animals on which the anemone lives, touch one of these tentacles, the anemone forces a large part of the water out of itself, shrinks up around its food and becomes a little upside down cup of an animal, with thin walls.
The sea-anemone not only looks like the flower of that name, but it has something that reminds us of the vine called the Virginia Creeper. The anemone is fastened to a rock by a sucking disc. It holds on with this sucker a great deal tighter than the vine clings to a wall it is climbing, with its little sucker feet. If you try to pull a sea-anemone up, you might think it has a strong root running down into the rock. But it has only a sucker foot for clinging. Sea-anemones have been known to move, but as a rule they spend their lives contentedly, fastened to rocks near which they are born.
This use of a sucker foot by the sea-anemone and the vine, is one of the many cases in which nature gets hold of a good idea and uses it over and over again. And she uses the sucker foot for plants and animals just as she uses the seed or egg for ferns and fishes, butternuts and butterflies. She gave the sea-anemone a sucker foot because he can get along best by clinging to a rock, and she gave the vine sucker feet to climb rocks and trees with. When the sucker foot idea once got into the two families of living things, Mother Nature seemed to say:
"Now all of you children who can use it, may have this little sucker foot."
