tched and followed.

Keep your eye fixed on the little black and white ball of jelly and before
long, gradually and yet with never a halt, a tiny furrow makes its way
across the surface, dividing the egg into equal halves. When it completely
encircles the sphere you may know that you have seen one of the greatest
wonders of the world. The egg which consisted of but one cell is now
divided into two exactly equal parts, of the deepest significance. Of the
latter truth we may judge from the fact that if one of those cells should
be injured, only one-half a polliwog would result,--either a head or a
tail half.

Before long the unseen hand of life ploughs another furrow across the egg,
and we have now four cells. These divide into eight, sixteen, and so on
far beyond human powers of numeration, until the beginnings of all the
organs of the tadpole are formed. While we cannot, of course, follow this
development, we can look at our egg every day and at last see the little
_wiggle heads_ or polliwogs (from _pol_ and _wiggle_) emerge.

In a few days they develop a fin around the tail, and from now on it is an
easy matter to watch the daily growth. There is no greater miracle in the
world than to see one of these aquatic, water-breathing, limbless
creatures transform before your eyes into a terrestrial, four-legged frog
or toad, breathing air like ourselves. The humble polliwog in its
development is significant of far more marvellous facts than the
caterpillar changing into the butterfly, embodying as it does the deepest
poetry and romance of evolution.

Blue dusk, that brings the dewy hours,
Brings thee, of graceless form in sooth.
Edgar Fawcett.

INSECT PIRATES AND SUBMARINES

Far out on the ocean, when the vessel is laboriously making her way
through the troughs and over the crests of the great waves, little birds,
black save for a patch of white on the lower back, are a common sight,
flying with quick irregular wing-beats, close to the surface of the
troubled waters. When they spy some edible bit floating beneath them, down
they drop until their tiny webbed feet just rest upon the water. Then,
snatching up the titbit, half-flying, they patter along the surface of the
water, just missing being engulfed by each oncoming wave. Thus they have
come to be named petrels--little Peters--because they seem to walk upon
the water. Without aid from t