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 The majority of gastropods have a single, usually spirally, coiled shell into which the body can be withdrawn.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.
Bleeding ulcer in the stomach or the upper part of the intestine can cause severe blood loss resulting in life threatening anemia. Bleeding ulcer may develop quickly in some patients taking certain medications. Patients presenting with bleeding ulcers may or may not have the typical symptoms of stomach ulcer.