mussel Mytilus edulis and allied species, an edible bivalve with worldwide distribution and importance. Their dark blue or blackish shells are a familiar sight at the seaside, and ‘wild’ mussels (if one can use the term for a creature of sedentary habits which feeds innocuously on the nutrients which it can filter out of sea water) have been gathered and eaten since remote antiquity. But the introduction of myticulture, as the culture of mussels is called, in France in the 13th century raised the consumption of mussels to a new plane; and the development in Spain of a new method of rearing mussels on ropes suspended from rafts has transformed the industry in the latter part of the 20th century.