All annelids except leeches also have chitonous hair-like structures, called setae, projecting from their cuticle. Sometimes the setae are located on paddle-like appendages called parapodia. ... The internal organs of annelids are well developed. They include a closed, segmentally-arranged circulatory system.

Where are the annelid setae found?

Setae generally arise from the ventral (lower) surface of the body.

What do annelids use setae for?

The bristles or setae help anchor and control the worm when moving through soil. The bristles hold a section of the worm firmly into the ground while the other part of the body protrudes forward.