The small tip is the tail angle of the silkworm, which is the part where the tail of the silkworm stands up. According to the size, firmness and blackening degree of the tail angle, the health and maturity of silkworm can be judged. The tail horn is firm, the silkworm body is tough, and the body color is innocent, indicating that the silkworm is growing well, strong and easy to raise. On the contrary, the tail horn turns black and the top tip becomes sharp, indicating that the silkworm is aging fast.
Diptera larvae used to live in water and have breathing tubes on their backs. This form is similar to that of silkworms on land, and entomologists have classified it as Ampelopsis, so mosquitoes of Diptera and silkworms of Lepidoptera are closely related in taxonomy.