Earthworms
Earthworms are the common name for the largest members in the phylum Annelida. Earthworms are in this phylum because they are called "ringed worms".
Earthworms can be found on the surface of the ground after heavy rain storms, where the storm floods the soil with excessive water. However, if the surface where they find themselves is unexpectedly paved, rocky, or hardened, they may become stranded, which means they may be potentially suffering injury or death from natural causes such as heat exposure, dehydration, or survival of the fittest. The digestion process begins in the mouth, where food is sucked in by a muscular pharynx. Then, food goes down the esophagus through peristalsis. Next, the food is stored in the crop, which retains food and has the ability to expand. From there, food enters the intestine which has the ability to absorb food, and then food exits through the anus. A rectum is unnecessary because earthworms live and thrive in moist environments and thus does not require excessive amounts of water.
Earthworms can be found on the surface of the ground after heavy rain storms, where the storm floods the soil with excessive water. However, if the surface where they find themselves is unexpectedly paved, rocky, or hardened, they may become stranded, which means they may be potentially suffering injury or death from natural causes such as heat exposure, dehydration, or survival of the fittest. The digestion process begins in the mouth, where food is sucked in by a muscular pharynx. Then, food goes down the esophagus through peristalsis. Next, the food is stored in the crop, which retains food and has the ability to expand. From there, food enters the intestine which has the ability to absorb food, and then food exits through the anus. A rectum is unnecessary because earthworms live and thrive in moist environments and thus does not require excessive amounts of water.
Leeches
Leeches are segmented worms that belong to the phylum Annelida and are similar to earthworms in the way that they are both hermaphrodites and they both share a clitellum. The majority of leeches live in freshwater environments, while other species can be found in terrestrial and marine environments, as well. Most leeches are predominantly blood suckers that feed on blood from vertebrate and invertebrate animals. Historically, leeches has been used in medicine and medical experiments to remove blood from patients. For leeches, the digestive system starts with the jaw, which is located ventrally on the anterior side of the body. It is attached to the pharynx and also the esophagus, extending to the crop and gizzard, which leads to the intestines and finally ends at the posterior sucker. The crop allows a leech to store blood up to five times its body size, and, because the leech produces an anticoagulant, the stored blood remains in a liquid state. Due to this ability to hold blood without the blood decaying and the appearance of bacteria, most leeches only need to digest food twice a year.
Lugworms
The lugworm, also known as the sandworm, is a large marine worm of the phylum Annelida. Its coiled castings are a familiar sight on a beach at low tides but the animal itself is always in camoflauge except by those who, from curiosity or to use as fishing bait, dig the worm out of the sand. When fully grown, the lugworm off the coasts of Europe can be up to 9 inches long and 3/8 inch in diameter. Other species on the North American coast range from 3 to 12 inches. The lugworm's body is like that of an earthworm. It can also be ringed or segmented. Also, they are hermaphroditic but they have bristles along its sides as well as gills. The anterior (head) end, which is kept well below the surface at the bottom of the J, ingests sand, creating a closed, funnel-shape in the sand surface above the head. The worm swallows sand and mud, which binds to the mucus secreted on the everted proboscis. When the proboscis is inverted, the material sticking to it is pulled into the digestive system. This is how leeches digest food into their body. Organic matter ingested with the sand is rapidly digested and the processed sand is periodically defecated at the surface near the tail end of the burrow in a distinctive long, coiled casting.