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I am sure that most of you will be able to read the Tale of the Tadpole in your aquarium tank. Probably you have quite big tadpoles by now and know a good deal of the life-history of the funny little creatures.

Who knows why the frog puts her eggs into jelly? It seems rather a queer thing to do, doesn’t it? What a lot of eggs a frog lays! You have seen the spawn floating at the top of the water in great masses, I expect.

Have you picked up—or tried to pick up—any frog-spawn in your hands? It is so difficult! It slips out of your fingers and flops back into the water. It is too slippery to hold—and too slippery for any hungry creature in the water to eat! A tiny hatching tadpole would be a tasty mouthful for, say, a fierce water-beetle—so the jelly is put round the egg to guard it. Ducks are about the only things that can eat frog-spawn—and even then it sometimes slips out of their beaks and they have to try again! It is no good looking for little water-creatures in a pond where ducks live, for the ducks eat everything they find!

The jelly always floats to the surface, so that the sun can shine down on it and hatch the eggs. At first the little black eggs in the middle of each blob of jelly are quite round—then they get longer, like tiny sausages, or fat commas—and then at last the jelly begins to fall to pieces and the little black specks float out. They are the tiniest of tadpoles, just able to wriggle about. They hold on to the jelly at first, and then, when they are stronger, they float to the nearest water-weed.

How queer they look, these wriggling tadpoles! They have a long head and body ending in a tail. We cannot see any eyes or mouth. They cling to the water-weed by means of little suckers under their heads. I expect you have seen them doing that in your aquarium.

In a short time we can see yet another change in their shape. The head becomes distinct from the body, a proper little mouth forms, and something grows out of the tadpole’s sides—four feathery-looking things. What are they? They are gills to help the tadpole breathe whilst it is in the water. Have you seen them?

THE LIFE-STORY OF THE FROG, FROM EGGS TO FULL-GROWN FROG

Our tadpoles soon learn to swim about all over the place, and we can watch them feeding on the water-weed in our aquarium. They grow bigger and fatter. The feathery-looking gills disappear! They gradually shrivel up, because better gills grow inside their bodies, and they do not need the outside ones any more. Perhaps you have seen all this happen already, and your tadpoles are now big healthy-looking creatures, round and fat. You really cannot tell where the head ends and the body begins!

They are not quite so black now. Look for their bright eyes. Can you see them? They need other food than the water-weed—they like the little water-fleas and other tiny creatures almost too small for us to see, but which live in crowds in pond-water. That is one reason why you must put pond-water in your aquarium, and not tap-water. The tap-water has no water life in it, but the pond-water has plenty. If you will put a cupful of fresh pond-water into your tank once a week you will find that your tadpoles like it very much and flourish well. The tank-water evaporates, so you must keep up the water level.

Tadpoles also like a bit of raw meat occasionally. Tie a piece to a string and hang it over the side of the tank for a day or two each week. You will see the tadpoles come and nibble at it with great enjoyment. Take it out before you go home after school. If any bit of it falls off, do not leave it to decay in the water. Spoon it out.

Tadpoles will be frogs when they grow up, so they must grow legs. Watch your tadpoles. One day you will see that one or two have tiny back legs growing. Ah, now they really begin to look more frog-like, do they not?

One of the differences between frog and toad tadpoles is that the front legs of the toad are noticed first. The front legs of the frog-tadpoles are growing too, but they are hidden at first behind the gill-cases, and we do not notice them.

What funny little legs they are! Have they toes? How many? Does the tadpole use his new legs to help him swim, or does he still use only his big tail? Watch and see.

“Oh,” you will say one day, “his tail seems to be much shorter!” So it is. It is disappearing! The tadpole’s body is using it up, drawing out the goodness in it, making it become smaller and smaller—until at last there really isn’t any left! And when that happens we cannot call the tadpole a tadpole any longer; he is a tiny frog. He could sit on a sixpenny bit easily, he is so small. He has four little legs with toes on the end, and his body is ridged on the back like a grown frog’s.

The tiny frog does not like to keep in the water all the time—he keeps bobbing up to the surface and sticking his blunt nose out. He does not breathe with gills now, but with lungs, like us—he is an air-breathing creature, not a water-breathing one. What a number of changes he has had in his short life! He is soon going to become a land-creature now, so he practises breathing the air at the top of the pond. Or, if he is in your aquarium, he clambers up the stones you have put there, and sits on the one you have allowed to peep out of the water. He is very comfortable there, and he will sit and blink at you (for he has grown eyelids now, too!) and enjoy himself.

You cannot very well feed small frogs, for they need flies and other insects, so the time has come for you to say good-bye to him and put him back in the pond, with all the other small frogs that have grown up there since the spring-time. What a large world the pond seems to him after his sheltered aquarium! How full of dangers! I expect for the first few days our little frog has a great many frights.

If it is hot, dry weather the small frogs remain in the pond or in the muddy places near it. They are waiting for a good rainstorm before starting out on an exciting journey to find a home for themselves. One day the rain pours down and soaks everything. Good! That is the signal for the little frogs to leave the pond and go to the ditches and meadows.

Each little frog finds a nice damp spot for itself. Some hide under leaves. Some crawl under stones. Some squat at the bottom of ditches. And there they stay till they are hungry and the night is cool and dark. Out they come and hunt for slugs or any other tasty creature. They are fond of flies, too, and these they catch in the daytime, when any unwary insect comes near their hiding-place. How do they catch flies? Have you ever seen a frog or toad catching one?

Both frogs and toads have a queer tongue. It is fastened at the front of their mouths instead of at the back like ours, and so they can flick it in and out a long way. It is sticky at the tip, and when the frog sees a fly perching near by he flicks out his ready tongue, the fly sticks to the tip, the frog draws in his tongue—and swallows the fly! It is all done so quickly that it seems like magic.

A TOAD IS A GOOD FRIEND IN OUR GARDEN, FOR HE EATS SLUGS AND MANY OTHER INSECT PESTS

Do you know the difference between a frog and a toad? The frog is smoother-skinned, and he has a startling habit of suddenly jumping high into the air. This is useful to him when an enemy sees him. The toad has a rough, warty skin, and he crawls, instead of jumping. On his back he has a great many little bags holding a stinging liquid, and if an enemy tries to bite him the toad squeezes out his poison, which tastes so nasty that his enemy leaves him in disgust. The toad lays eggs in long strings of jelly, not in masses, like the frog.

In the autumn the frogs and toads find damp places to sleep in. The frog likes the bottom of a pond. The toad likes a hiding-place under a big stone. There they stay all the cold winter through, hearing and seeing nothing. In the warm spring-time they wake up—and once more the ponds become full of frog-spawn, and the Tale of the Tadpole begins all over again! Our little one-year-old frogs do not lay eggs—they are not grown-up yet, and will not be full-grown frogs until they are three or four years old—but the old frogs lay their eggs, and once again we see hundreds of little tadpoles wriggling gaily.

THINGS TO DO

1.

Look at your tadpoles carefully. Draw one. When you notice any difference, draw one again. Put dates each time.

2.

Tell the Tale of the Tadpole shortly, from the spawn to the frog.

3.

What is the difference between a toad and a frog? Do you know one from the other? If you do not, try to find out this summer.

4.

Tame a toad if you can. He likes to be tickled on his back with a straw.

5.

Look at the eyes of a toad. They are unexpectedly lovely.