wings of the larva do not grow at each moult like the wings of the
grasshopper.

The larva never gets beyond short little wing pads. See John's eyes
twinkling! I believe--yes, he has! He has brought us the cast-off skin
of a cicada to look at.

[Illustration]

Why, John, you are like a good fairy to us to-day, giving us just the
things we want just when we want them.

Now, see this little shell. See the front legs, like strong paws to dig
with. And see its little glassy eyes, and its little wing pads!

It is a perfect cast of the cicada larva.

Yes, May, this little cast is made of chitin, and it will last a long
time. Chitin is a very indestructible substance; even fire will not
destroy it, but in course of time the moisture and the acids in the
earth destroy it, so that at last the millions of cicada shells and
grasshopper cast-off skins, which are also of chitin, and cricket
moults, and all the other little cast-aside chitinous overcoats of the
insects, return again to the earth and the air whence they came. The
minerals and gases that compose them let go of each other, as it were,
and the chitin is no longer chitin.

Amy says she has seen these little cicada shells hundreds of times but
did not know what they were.

Yes, we are sure to find them almost every summer.

If we look, we will also find other larvae shells. Down in the grass are
the cast-off coats of the grasshoppers and the crickets.

All we need do is to look, and we shall be sure to find them--like
unsubstantial ghosts of the active little wearers.

No doubt you all have heard of the seventeen-year locusts. They, too,
are cicadas, and they look very much like this one, only it takes the
young ones seventeen years to complete their growth.

Think of living in the ground and sucking the juices out of the earth
and of tree roots for seventeen years!

[Illustration]

How would you like to do it?

But no doubt the cicada is quite happy living in this way.

At the end of seventeen years the cicadas come up out of the earth in
great swarms.

They cast their skins for the last time. The queer little shells are
seen everywhere, and the air resounds with the songs of the freed
prisoners.

In the South it takes only thirteen years for these cicadas to develop.

[Illustration]

I once went up the side of a beautiful mountain in North Carolina, where
was such a mighty host of cicadas in the trees that I could not hear my
companion speak,