Snail,oyster,Dentalium,Chiton
Mollusks have soft body and hard shells but some don't even have shells.
Slugs,Octopus
they live in the shells.
Mollusks are soft bodied animals that can have no shells,1 shell or even 2 shells. Snails, clams, sea slugs, clams, scallops, oysters, octopuses, and squid, are some types of Mollusks.
Conchology is the study of mollusk shells, therefore a conchologist is someone who studies mollusk shells. Some confusion can arise as malacology is the study of mollusks as whole organisms, while conchology only studies the shells themselves.
most have shells
They have shells.
Mollusks are defined as Bivalves. They are called Bivalves because they have two shells. Cnidarians such as Jelly Fish do not have shells which define a bivalve (mollusks).
clown fish
they grow shells and some have claws. i know there are other things mollusks do for survival, but i cannot think of them off of the top of my head. PLEASE EDIT!
crustations
Yes, they are mollusks as well