The excretory system of the Lumbricus terrestris (Common Earthworms) is a three-step process that relies on the organism’s tubular organs known as nephridia. The process begins with filtration, when water and dissolved materials are filtered out of the ventral blood vessel into the body cavity and then into the funnel-like pores on the nephridia. A majority of the body segments in Lumbricus terrestris contain two nephridia that connect the segments. The nephridia also connect to the openings in the integument and allow fluid from the tube to be released into the environment. While the watery substance is in the tube, it undergoes absorption as some important substances are retrieved from the tube and brought back to the blood and secretion during which substances, mostly toxic, are carried from the blood or body fluid into the tube. Lumbricus terrestris uses it excretory system to primarily excrete ammonia, which is dissolved away in the moist soil.