Moulting - leaving the "old coat" behind!

The skin of the silkworm sheds from the head toward the back, and the silkworm literally "walks out of his skin", leaving it in a little pile behind him. Especially in the later moults while this is happening, the silkworm is "torpid", appearing to be asleep. It's best not to disturb them at this time.

The first moult. 
The skin is receding from behind the head. They still have little black heads.

The second and third moults

Torpid silkworms appear to be sleeping.

Notice the black head has now changed. It came off like a little cap and was left behind.

Skins are left behind in little piles.

The fourth moult.

A skin left behind.

Photography: M. Vaughan