R. Cadwallader Smith

Froggie's Family

IN early Spring-time, when "pussy-willows" are beginning to look gay, and the Marsh Marigolds flaunt their shining yellow in the swamps, Froggie journeys to the water, to lay her eggs. In a few days' time, masses of jelly, dotted with little black spots, show where she has been. But we see no sign of Froggie, for she has hidden in the grass and weeds, leaving her eggs to look after themselves.

"But all frogs do that," you may say, "and they never behave in any other way." It is quite true that our frogs never show any regard for their families. Some frogs of other lands behave in a very different way, however, as we shall see later in this lesson. First let us see the many curious things that happen to Froggie's eggs.

The frog's life is like a story with many chapters, though very few of Froggie's big family live from Chapter 1 to the end of the story! The eggs, tadpoles, and baby frogs are, to many creatures, what chocolate-cream is to boys and girls—something to be made an end of at once! So the frog's family daily gets less and less! As the eggs have no protecting nursery, it is as well that the frog—like the cod and herring we saw in the last lesson—lays so many of them!

Now fishes and frogs, as you know, are not related. They belong to two distinct groups in Nature's great family, but in one thing at least they are alike. Both the baby frog, and the baby fish, when they first hatch into the world, appear in a form quite unlike that of their parents. They are, in fact, in a larval stage.

About two weeks after Froggie laid her eggs, a little black creature wriggles out of each jelly envelope, in which it has passed Chapter 1 of its life. In Chapter 2 it is very lazy. It does nothing but cling to the water-weed by means of two suckers under its head. It has no eyes and no mouth. It is simply waiting for its mouth to grow. And, as it is not really a tadpole yet, we must call it a larva.  It breathes by means of tufts that branch from each side the "neck."

Chapter 2 ends in a few days, when our larval frog has a mouth. A very small mouth, but a strange one! It is armed with wonderful rows of rasps, or teeth. If our eyes were immensely strong, we could count more than 600 of these tiny teeth! The two beady eyes also appear now, but the breathing tufts soon disappear.

Our larva has gone a stage farther in its life-story. It has reached Chapter 3 in which it is a tadpole, breathing like a fish through slits in each side of its neck. It eats greedily, and grows. For the most part it feeds on particles of weed, but is quite ready to dine off the dead bodies of its own relations! Its body is inky black with gold spangles, and, like a fish, it swims by wriggling its strong tail.

In Chapter 4 of its story we must call it a frog-tadpole, for its legs begin to show, first the long hind ones, and then the front ones. It is leaving its baby tadpole period, and nearing the time when it will be a perfect frog. But first it has some most important changes to make, before it can enter Chapter 5 of its life, and leave the water.

The frog-tadpole ceases to feed, and casts off its gills and jaws! Other wonderful changes occur in its body: it begins now to come to the surface of the water. Perhaps you can guess the reason? It has given up breathing by means of gills,  as a fish breathes, and now needs air to fill its lungs,  just as we do. At last it has gone through all the stages of its babyhood, and swims ashore as a little frog. It has reached the last chapter of its life as a water-baby: if it does not now hurry ashore all the tadpoles seem to take a delight in nibbling its toes!

Before entering on its new life on land, it throws away its old clothes. In other words, it casts its skin: its tail, as you see in the picture below (which also shows the cast-off skin), is now nearly all gone. Has it dropped off? No, it was not wasted, but used up as food by the body, during that eventful Chapter 4, when so many things are happening to the frog-tadpole that it is unable to eat.

Young Frog with its Cast Skin

Our baby frog sets out, with thousands of others, to seek its fortune on land—only to meet more enemies! Being no larger than your finger nail, it can hide away in the daytime in any tiny crevice, coming out at night when the earth is moist. After a spell of dry weather, the first rain-storm brings the froglings out in their thousands, until the earth seems alive with them. Indeed, it used to be said that they had "all fallen down with the rain"! They set out to explore the world—much to the delight of all the ducks in that district!

We leave them to grow up into big frogs, while we skip several thousand miles in search of other frogs. In the country of Brazil lives one which is called by the natives "The Blacksmith," for its voice resounds like the hammer on the smith's anvil. But it also has the habit of making a kind of nursery for its eggs and young.

To make the nursery, the female frog collects mud for building material, and uses her feet as a mason uses his trowel. She plasters the mud together, and so constructs a round wall in the shallow water of a pond or marsh. She works until the edges of this mud basin show above the water. She then levels the floor, lays her eggs inside the basin, and leaves them.

Another frog of the same country makes a neater nest than that. She climbs up the stem of a plant. Then, with the help of her mate, she bends a leaf into the shape of a funnel. In this odd nest she deposits her eggs, where they are fairly safe from enemies.

But there are other frogs, and toads also, which are not content with such nurseries. They make no nest at all, but prefer to carry their eggs about with them! Toads, as you may know, lay their eggs in long rows, like so many pearls in a necklace, and leave them in the water. But a foreign toad has the odd habit of winding the eggs around his hind legs!  With this jelly string coiled about him, he hides away until night-time, when he comes out to eat and bathe the eggs in a pond or in dew. The female toad has nothing to do with them once they are laid: but Mr. Toad makes himself useful, and acts as a nurse as well as a nursery!

We will look at one more nursery, and that one perhaps the oddest of all! In this case we find a male frog taking charge of the eggs; and instead of placing them on his body, he thrusts them into a pouch, or bag, under his mouth! This is surely an odd place for a nursery! Of course his family is a small one—about a dozen eggs, as a rule. This frog was discovered by the great naturalist Darwin: it is also famous as being the smallest frog in the world—it never grows beyond half an inch in length!

Though the queer frogs and toads we have glanced at are dwellers in foreign lands, you may sometimes see them at the Zoo. Two things we must notice before we leave them: one is, that the male  frog or toad is sometimes the nurse; another is, that they have small  families, and not large ones like those of our own frogs and toads. Can you guess the reason?