An adult earthworm develops a belt - like glandular swelling, called the clitellum, which covers several segments toward the front part of the animal. This is part of the reproductive system and produces egg capsules. The posterior is most commonly cylindrical like the rest of the body, but depending on the species, may also be quadrangular, octagonal, trapezoidal, or flattened. The last segment is called the periproct; the earthworm 's anus, a short vertical slit, is found on this segment.
what is the last segment of earthworm called and what organ does it contain
periproct anus