Scallops are bivalves characterized by lying down on a substrate and being non-attached to it, however many artistic representations tend to apply this to other bivalves as well. Their shells are flat and, in general, slightly corrugated, varying between round or triangular shape and having distinctive elongations in the region of ligament between valves.
Some scallops exhibit the capability of propelling themselves by expelling water out of their shells through rapid opening and closing movements.
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