Snails and Slugs: Phylum Mollusca, Class Gastropoda. The Class Gastropoda (in Phylum Mollusca) includes the groups pertaining to snails and slugs. The majority of gastropods have a single, usually spirally, coiled shell into which the body can be withdrawn. The shell of these creatures is often what is recovered in a fossil dig.
Causes of bleeding in the stomach can include: 1  Ulcers: Ulcers may enlarge and erode through a blood vessel, causing bleeding. 2  Gastritis. 3  Cancer. Gastric varices.  Dieulafoy 1  lesions. Portal gastropathy.
1 Abdominal distension: Your belly sticks out more than it did before without weight gain.  Abdominal pain: This is rare in colon cancer. One cause is tearing (perforation) of the bowel. Leaking of bowel contents into the pelvis can cause inflammation (peritonitis) and infection.