A reference to insects having no metamorphosis (no major change in physical form): The ametabolous Apterygota is wingless and its larvae hatch from eggs in a form essentially identical to the adult except for the size and undeveloped genitalia. The llarvae develop in which the size increases at each molting, or periodically shed a part or all of the outer covering of their bodies (hair, skin, or feathers, etc.) which is then replaced with a new growth.