The other bivalve that we grow, the bay scallop (Argopecten irradians), has some distinct differences from hard clams and oysters. Firstly, it neither burrows into the bottom nor cements itself to substrate. It retains a foot, similar to the hard clam, but also has the ability to swim by quickly opening and closing its shells/valves. The bay scallop also has many eyes that it uses to detect shade, thus the ability to "see" when a predator is approaching.
Scallop Anatomy
It is a simultaneous hermaphrodite, in that it produces both eggs and sperm at the same time. Juvenile bay scallops are often found attached to blades of eelgrass (Zostera marina) or other sea grasses, with larger animals resting on the bottom. The adductor muscle of the bay scallop is most often eaten, but most of the remainder is also edible. Unlike hard clams and eastern oysters that can live for decades, the life cycle of the bay scallop is about 2 years.