The bivalves

Post on 11-Nov-2014

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Transcript of The bivalves

Class Bivalvia – The Bivalves(clams, mussesls, scallops, oysters)

Feeding-Most are planktivores-Incurrent & excurrent Siphons-Important filter feeders-up to 25 gallons of water/day

Pearl Formation• Mostly in oysters• Protection against

parasites or grains of sand

• Often not round• Natural pearls are

more costly• Cultured pearls are

made by inserting an object in the oyster