Scallop seashells are marine bivalve mollusks which are similar to oysters and clams. The difference is scallop can swim by opening and closing their shells. By snapping their shells together, they propel themselves rapidly in a zigzag direction. Most are tropical, but a few live in polar waters. Scallops are fished commercially for the large single muscle which is excellent eating. Copyright© 2004 - 2022 Naples Sea Shell Company ®