In April the trees burst forth with their bright green leaves, and the grass looked fresh under the power of the warm rains.

In May the many-tinted flowers appeared, filling the air with their sweetness, and brightening the fields and gardens with their gay colors.

At this time another great change came over the old grub.  It showed signs of life again; but it was now no longer a caterpillar—­it was something else.

It wriggled and turned in its narrow little home, and seemed anxious to get out and look at the sunshine and flowers.  It bumped its head up and down until it succeeded in pushing off a little door.

When the door was off, and the bright sunlight shone in, this little occupant of the chrysalis took a look at itself.

It saw that during its long winter’s nap, it had acquired a pair of beautiful wings, and its legs had grown longer and stronger than they were before.

Crawling out of the chrysalis, and taking a position on a branch of the tree, it discovered that instead of a caterpillar, it was now a beautiful butterfly.

It was a kind that is called the swallow-tail butterfly, because each of its wings tapered to a point, something like the tail of a swallow.  We will call the butterfly, Miss Swallow-tail, and now let us see what her next move was.

Her wings were damp and heavy, and she stood shivering and trembling; for although she had six legs, they were weak, having never before borne such a weight.

But fresh air brings strength; so she soon felt like trying to walk.  At first her movements were sluggish, but she finally reached a sunny spot where she dried and warmed herself, giving her wings a little shake now and then, until they opened grandly above her back.

And how beautiful they were!  Dark brown, bordered with two rows of yellow spots; and there were seven blue spots on each of the hind wings.

As she stood there in the sun, a little wind came along and raised Miss Swallow-tail off her feet.  She spread her wings to keep from falling, and found herself floating in the air.

This proved to be such a delightful way of traveling, that she lifted her wings occasionally, and so kept herself floating; and in a short time she learned to turn in any direction she chose.

As she flew along, growing stronger every minute, she was attracted by the bright colors of a flower, and stopped to admire it.

The sweet perfume tempted her to taste, and unrolling her long tongue from under her chin, where she carried it, she put it down into the flower and drew up the honey hidden there.

Miss Swallow-tail had wonderful eyes.  All butterflies have wonderful eyes.  If you will look at them through a microscope you will find that each eye is composed of a great many smaller ones, that can see in all directions.

They have great need of such eyes, because there are so many birds and other hungry creatures, that want to eat them.