The larva of a housefly is 2mm long, devoid of head and legs. Its body is tapered in front and thick from behind. The body is covered by a thin cuticle. A pair of mandibles project in front from the rim of the mouth that facilitate locomotion in larva and help in tearing the food particles. The larval stages are divided into first, second and third instar larva. After 3,4 days, the third instar larva metamorphoses to form a pupa.