Four stages of a Luna Moth

The Egg (12 to 14 days) Adult female moths lay up to 200 eggs in small groups on the leaves of walnut trees. These eggs are as small as the top of a pin. Ten days later, small caterpillars eat their way out of the eggs.

The Larva (3 1/2 to 4 weeks) The newborn caterpillar eats constantly—several leaves every day—growing quickly. Soon the caterpillar's skin is so tight, it starts to split. The caterpillar wriggles out of its old skin, having formed a fresh, new skin underneath.

The Cocoon/Pupa (2 to 3 weeks) At 2 1/2 inches long, the caterpillar is now fully grown. It stops eating, and looks for a safe place to make a cocoon. Making sticky thread from a hole near its mouth, the caterpillar begins winding the thread round and round its body. The caterpillar pulls a leaf around the cocoon, securing it with the sticky thread.

One week later, while the caterpillar is still encased in the cocoon, the caterpillar's skin splits open. What's inside? A pupa, with a moth growing inside. In three weeks the moth is ready to come out. The moth pushes from inside until the skin of the pupa splits. Next, the moth makes a special juice and softens the cocoon, so it can push its way out!

The Moth (1 week) At first, the Luna Moth's wings are soft and crumpled. In 20 minutes, the wings are full size, and almost dry. But wait, the moth can't fly yet! Once the moth's wings are dry, it opens them out, and then rests until nighttime. Once it gets dark, the moth will fly away to find a mate. Luna Moths only live for about 1 week.