The diagram illustrates the life phases that the silkworm passes through during its lifetime.
Overall, the silkworm passes through four stages which start with moth that becomes eggs and silkworm larva to cocoon from which silk thread and larva emerge. Then finally moth, starting the life cycle again.
Initially, moth lays eggs and then eggs are developing to be larva, which is called silkworm larva. The larva is fully developed in 10 days and grow to eat mulberry leaf as their food. Four to six weeks later, as the larva grows, it develops silk thread which is use to cover its body for the next stage. At this stage, their body is partly covered in silk thread.
Eight days after silk thread was developed, it becomes cocoon which where the larva body is fully covered with silk thread. Eventually, in sixteen days, cocoon develops their body to a moth that is ready to start the life cycle again.