Silkworm

Silkworm, caterpillar of a moth (Bombyx mori) that, like many other caterpillars, spins itself a cocoon of silk in which it pupates. The cocoon is, however, especially thick and may be composed of a single thread commonly 3,000 ft (915 m) long. This is unraveled to provide commercial silk. Originally a native of China, B. mori has been introduced to many countries. The caterpillar, which takes about a month to develop, feeds on the leaves of the mulberry tree.