Imago ( adult stage ) of the Chinese silkmoth, Samia cynthia, in process of inflating its wings. S. cynthia is a native of Eastern China, where its cocoons are one source of wild silk. It is now found locally in the wild in Europe and the USA, the result of failed attempts to exploit its silk production. The picture shows a adult insect 15 minutes after emergence from the cocoon (white, top centre) in which it has spent the previous weeks undergoing metamorphosis from the larval stage. Inside the cocoon, the wings are crumpled and flaccid; on emergence the insect hangs from a twig and pumps haemolymph into the wing veins in order to cause the wings to expand. This fluid is withdrawn once expansion has occurred, and the chitin comprising the wings then hardens over a period of 30 minutes or so. In this picture the wings have not reached their full size, and remain soft and flexible.