spinning glands, insect glands that produce a substance (a mixture of fibroin and sericin proteins), which hardens in air into a strong silk thread. Silk stands out. insects and serves for building cocoons and nests, folding and entangling leaves, and attaching the pupa.
They are usually modified lower labial (labial) salivary glands (in all caterpillars, larvae of many hymenoptera). In caterpillars, tubular, connecting into a common excretory duct, opening at the top of the lower labial papilla. In the region of the duct, there is a complex pressing apparatus that regulates the thickness of the thread. In the larvae of some weevils, in a number of lacewings, silk separating functions are performed by Malpighian vessels
