Changes in the first instar cuticle of Schistocerca gregaria before and associated with hatching

Size increases in the first instar cuticle are described in the pharate stage, at hatching and ecdysis, and in the hour following ecdysis. The ways in which the cuticle expands are described. Changes in colour and the mechanical properties of cuticle are described and related to changes in the different protein fractions extracted from the cuticle. A blood-borne factor is shown to affect darkening in the first instar.