Jan Jones, age 12, of San Diego, Calif., for his question:

Do all butterflies come from cocoons?

Insect collectors often gather cocoons from the winter twigs and take them indoors to hatch. The silken bundles are kept in glass jars with tops of perforated paper, and only an experienced expert can be sure what insect will emerge from this or that cocoon. But it will never be a butterfly, for the butterflies cannot spin silken cocoons.

The insects of the order lepidoptera develop through four life stages. They all start as eggs, and then they go through a larva stage as hungry, grubby caterpillars. Next comes the pupa stage, when the insects go into hiding and pass through a complete metamorphosis which changes them from caterpillars into winged adults. The word lepidoptera means scaly wings, and. All the glamorous butterflies and moths belong in this insect order.

During the pupa etage, an insect must be well protected from the weather and hidden, if possible, from its hungry enemies. The sleepy pupa may be sheltered in a leathery shell called a chrysalis, or it may be wrapped in a silken blanket called a cocoon. There are about a quarter of a million scaly winged insects, and most of them are moths. the handsome plyphemus moth may spin its barrel shaped cocoon on the ground or hitched to a hickory twig. This big, brown tinted moth, with a pair of blue eyes painted on its wings, is common all over our land. In the eastern states, the Cecropia moth slings a cocoon like a dusty hammock among the willow twigs, and the Prcmethea moth winds its cocoon in the faded leaf of a wild cherry tree.

But all butterflies spend their sleeping beauty stage encased in crusty chrysalises. The tiger striped caterpillar of the monarch butterfly wraps himself in a pale green scroll. You would have to stare hard to see it there, tucked among the pale green leaves of the mi1kweed. The dainty angel wings and the somber colored mourning cloak butterflies pupate in chrysalises like miniature seashells. The cabbage butterfly sleeps through its pupa stage in a chrysalis like a bundle of folded green leaves.

Some butterfly pupae hang from twigs or leaves, others sleep on or in the ground. But all of them are crusty chrysalises. For no butterfly can spin a thread of silk. And a cocoon is woven from threads or fibers of finest silk. Many of the moths weave cocoons of various kinds, but not all of them. Like their cousins, the scaly winged butterflies, many of the moth’s pupate as chrysalises.

Lepidoptera, the scaly wings, seems a strange name for this order of glamorous insects. But their ve1vety colors are caused by microscopic scales and flakes which crowd all over their soft wings. These scales are so fragile that they crumble to dusty powder when you handle the delicate insects.