Larval stage of development.
Contains the heart and the organs of digestion, excretion, and reproduction.
Layer of epidermis covering the visceral mass.
Space between the mantle and the visceral mass.
Paired clusters of nerve cells.
Main feeding adaptation of many mollusks.
Members of the largest and most diverse class of mollusks.
Mollusks whose shell is divided into two halves, or valves, connected by a hinge.
Where a current of water enters.
Where a current of water leaves.
Marine mollusks that mean "head-food."
Temporary storage area.
Muscular part of the gut which grinds the soil, releasing and breaking up organic matter.
Infolding of this intestinal wall increases the surface area available for digestion and absorption.
Muscular tubes that link the dorsal and ventral blood vessels near the anterior end of the worm.
Excretory tubules where earthworms eliminate cellular wastes and excess water.
Thickened section of the body where a film of mucus is secreted into.
Where the sperm from each worm moves through the mucus to this of the other worm where the sperm is stored.
Tough carbohydrate that is secreted from the clitellum of the worm.