ing some little creature which is content to find its home and its food in the dark ground. Nay, many animals for whom there is no chance of life on the earth, in the water, or in the air, find a refuge in the bodies of other animals and feed on them.
But in order that all these creatures may live, each in its different way, they must have their own particular tools to work with, and weapons with which to defend themselves. Now, all the tools and weapons of an animal grow upon its body. It works and fights with its teeth, its claws, its tail, its sting, or its feelers; or it constructs cunning traps by means of material which it sucks out of the water, as in the case of the oyster, or gives out from its own body, like the spider. It hides from its enemies by having a shape or color like the rocks or the leaves, the grass or the water, in which it lives. It provides for its young ones either by getting food for them, or by putting them, even before they come out of the egg, into places where their food is ready for them as soon as they are born.
So that the whole life of an animal depends upon the way in which its body is made; and it will lead quite a different existence according to the different tools with which life provides it, and the instincts which a long education has been teaching to its ancestors for ages past. It will have its own peculiar struggles and difficulties and successes and enjoyments, according to the kind of bodily powers which it possesses, and the study of these helps us to understand its manner of existence.
And now, since we live in the world with all these numerous companions, which lead, many of them, such curious lives, trying, like ourselves, to make the best of their short time here, is it not worth while to learn something about them? May we not gain some useful hints by watching their contrivances, sympathizing with their difficulties, and studying their history? And, above all, shall we not have something more to love and to care for when we have made acquaintance with some of life's other children besides ourselves?
The one great difficulty, however, in our way, is how to make acquaintance with such a vast multitude. Most of us have read anecdotes about one animal or another, but this does not give us any clew to the history of the whole animal world; and, without some such clew, the few observations we can make for ourselves are very unsatisfactory. On the other hand, most people will confess that books on zoölogy, where accounts are given of the structure of different classes of animals, though very necessary, are rather dull, and do not seem to help us much toward understanding and loving these our fellow creatures.
What we most want to learn is something of the lives of the different classes of animals, so that when we see some creature running away from us in the woods, or swimming in a pond, or darting through the air, or creeping on the ground, we may have an idea what its ob-
