mollusk
Mollusks are invertebrates such as snails, scallops, and squids. They have a hard outer shell. There is a layer of tissue called the mantle between the shell and the body. Most mollusks have tentacles for feeding and sensing, and many have a muscular foot. Mollusks also have a coelom, a complete digestive system, and specialized organs for excretion. The majority of mollusks live in the ocean. Different classes of mollusks have different ways of obtaining food.