Pupa

Stage 3 is the Pupa stage.  "After the final molt the caterpillar will keep its front 3 pair of legs. It will then crawl to a safer place where it can hang upside down from a leaf. The larvae will spin thread and attach its tail to its resting place. In roughly 24 hours, the skin will split down the back. Under this skin is called the chrysalis, which will harden and turn into a golden color. This is what protects the life that is contained inside, and the butterfly will stay in this state from 7 to 10 days."

Resource: http://www.uoregon.edu/~rarditi/page1/butterfly.htm