Silkworm pupa: In about 4 days, the silkworm will become a pupa. The body shape of silkworm chrysalis is like a rotating pestle, which is divided into three parts: chest and abdomen.

The head is small, with compound eyes and tentacles; The chest has chest feet and wings; There are 9 knots in the bulging abdomen, and professionals can tell the sex from the lines and brown spots on the abdomen of silkworm chrysalis.

When the silkworm chrysalis is just pupated, its body color is light yellow, the pupa is tender and soft, and it will gradually turn yellow, brown or brown, and the pupa skin will become hard. After about 12 to 15 days, when the pupa body becomes soft again and the pupa skin is a little wrinkled and brown, it will become a moth.

Silkworm moth (adult): Silkworm moth is shaped like a butterfly and covered with white scales, but it has lost its ability to fly because of its small wings. The head of silkworm moth is spherical, with compound eyes and tentacles protruding; The chest has a pair of chest feet and two pairs of wings; There is no abdominal foot in the abdomen, and the terminal body segment has evolved into an external genitalia.

Female moths are big and slow to crawl; Male moths are small, crawling fast, and their wings vibrate fast, looking for a mate. Generally, after mating for 3-4 hours, the female moth can give birth to a fertilized egg, and the male moth dies after mating. It takes a female moth about one night to lay about 500 eggs, and then she will die slowly.

The eggs laid by silkworm moths → hatch silkworms → pupate → moths will complete the cycle of a new generation, which is the life history of silkworms.