Molluscs comprise a large and diverse phylum of nearly 90,000 extant species that includes cephalopods (e.g., squid, octopus), gastropods (e.g. snails and slugs), and bivalves (e.g., clams, oysters and scallops). Molluscs are characterized by their mantle and presence of radula among other characters. Below are molluscs common in the plankton assemblages of Mid-Atlantic coastal waters. Read more about molluscs at Wikipedia.