An earthworm does not have bones and legs. Its body is made up of muscles. The body of an earthworm is made up of many rings loops joined end to end. It moves forward by the contraction and expansion of muscles. During movement, the earthworm first extends the front part of the body, keeping the rear portion fixed to the ground. Then it fixes the front end and releases the rear end. It then shortens the body and pulls the rear end forward. This makes it move forward by a small distance. Repeating such muscle expansions and contractions, the earthworm can move through soil. The body secretes a slimy substance to help with the movement.