Annelids II: Earthworms & Leeches
Class Oligochaeta: Earthworms; simple head, no eyes but light-sensory system on posterior segments; no parapodia
and deposits eggs and stored sperm; fertilization in cocoon
Class Hirudinea: Leeches; freshwater, external, blood-sucking parasites; flattened
Clitellum: secreted mucus holds worms together during mating; later secretes a cocoon with outer layer of chitin; worm moves “through” clitellum