The little mate being fond of play does not like to stay in the house long. She lays a few eggs about the size of poppy seeds. Then she bites a hole in the house and runs away! Next day little Mr. Stickleback goes to find her, and coaxes her back. This goes on for several days, until a great number of bright yellow eggs, like seeds, are laid in the nest. After this, it is a whole month before the little fish will hatch. Meantime other fish and other sticklebacks will eat them, if they get the chance. All that month the kind, brave little stickleback swims up and down near his nest, and drives off enemies. He will let no fish, not even his mate, come near his treasure. Finally, out come the wee, wee fish. Now the poor little father has a harder time than ever. The other fish want to eat up the young fry. The food of sticklebacks is grubs, tiny insects, and very small fry. As they are very hungry and greedy, they are on the watch to pick up the new little fish. But the stickleback, however hungry, never eats his own little ones. He leaves such vile conduct to the dog-fish. As the little ones grow, they are very active, and want to stray away from their home. Their father knows they would get into danger, so he watches, and chases each runaway back into its home bounds, where he can take care of them all. Finally, the little ones are so nearly grown that they can fight for themselves. They can pick up their own food, and make their own houses. Then they are allowed to go off and swim where they choose. As I have told you about a very little fish, I will now tell you something of a very big fish. The sturgeon is a great fish which lives in the waters of many countries. He is found in some of our rivers. The body and head of the sturgeon are partly covered with five long lines of great bony plates. These plates are grooved, and have a sharp point in the centre. They make good armor. Sturgeon are fond of playing and leaping from the water. They are often speared by people standing on rocks or in boats. I have seen very big ones taken from the Niagara River. In the Ohio and Mississippi the curious spoon-bill or paddle-fish sturgeon are found. In some of our other rivers the shovel-headed sturgeon lives. The flesh of the sturgeon is good for food. The Russians make isinglass from the air bladder of the sturgeon, and one or two kinds of food are prepared from its roe and flesh. Of the isinglass prepared from the sturgeon, jelly is made. Glue is very plentiful in the skin and bones of the sturgeon, and a kind of food is made from the spinal marrow. I need hardly tell you much about the uses of fish. You all know that they form a large part of the food of men, and many birds and beasts. Glue is made from fish-bones and skins. From many fish are made those substances that I told you farmers put upon their land to restore the minerals eaten out by the plants.