Chrysalis

Chrysalis of butterflies

A chrysalis (Latin: chrysallis, from Ancient Greek: χρυσαλλίς, chrysallís, plural: chrysalides, also known as an aurelia) or nympha is the pupal stage of butterflies. The term is derived from the metallic–gold coloration of the pupae of many butterflies, referred to by the Ancient Greek term χρυσός (chrysós) for gold. When the caterpillar is fully grown, it makes a button of silk which it uses to fasten its body to a leaf or a twig. Then the caterpillar's skin comes off for the final time. Under this old skin is a hard skin called a chrysalis.