Habit and habitat: Majority of the annelidanimals live in temperate and tropical counties of the world. They show wide diversity in their structure, habit and habitats. Many live in fresh water, saline water. Some occur in moist soil, some members lives in seashore, some in bottomof shallow sea, some species live in grooves on stone and soil.
a) Body metamerically segmented, body covered with thin cuticle.
b) Ciliated, glandular, coiled tubules named nephridium acts as excretory organ.
c) Generally setae are used as accessory organ for locomotion.
Example: Pheretima posthuma(Earthworm),Tubifex(Live in fresh water.
used as food of aquarium fish Hirudo madicinalis (leech).