FROGS AND TADPOLES.

BY E. S.

It is very interesting in the spring to watch the gradual development of
a frog from the egg, through the tadpole stage of its existence, till at
last it assumes its final form.

The old frogs emerge from their winter hiding-places in the mud, early
in the spring, and during April their eggs may be found floating on
almost every stagnant pond.

A group of these eggs in their early stages of development looks like a
mass of clear white jelly, containing numbers of black specks, each of
which is really the germ of the future tadpole.

In order to watch the development, a group of the eggs should be taken
and put in a shallow vessel of water, which, if kept in the house,
should have a bell-glass, or some other covering, over it, to keep out
the dust.

The jelly-like mass which envelopes the future tadpole is so clear that
all its changes can be easily watched.

First the head appears, then a flat tail, and in course of time the
nostrils, mouth and large eyes, till at length the completed tadpole
bursts open its gelatinous covering, and apparently not in the least
embarrassed by its new surroundings, begins swimming briskly about,
looking for something to eat.

The time occupied in hatching varies in different countries, according
to the climate, from four days to a month.

The following stages are even more interesting, especially for those who
can take advantage of the transparency of the parts to watch the
circulation of the blood through a microscope.

The body of the tadpole gradually gets broader, while the tail gets
thinner and thinner, till it finally disappears altogether; but before
that happens, its place has been taken by two hind legs, which first
appear under the skin and then gradually push their way through.

The fore legs next appear, and so on through all the stages of
development, till in a longer or shorter time, according to the amount
of warmth, light and food it can obtain, the complete frog appears.

But woe betide the unfortunate tadpole which, first of the shoal,
attains to the dignity of possessing limbs, for so ferocious are the
later ones, and so jealous of their precocious little brother, that they
almost always fall upon him, and not content with killing, never rest
till every morsel of him is eaten.

And unless several of the tadpoles assume their final change about the
same time, this proceeding is repeated till their numbers are very