The French love oysters (as do I). They harvest close to 130,000 tons each year, making France the largest producer in Europe and the fourth largest in the world. Nearly all are consumed domestically, and almost all are eaten on the half shell. Unlike the United States, cocktail sauce and horseradish are unheard of. The French dress their oysters with a splash of sauce mignonette, a simple concoction of red wine vinegar and minced shallots, sometimes showered with black pepper. The purists, eat them just as they are (au nature), with thin slices of rye bread and unsalted butter intended to prepare the palate for the next oyster. And, but of course, a chilled glass Sauvignon Blanc.

The French eat oysters all year round, though the best season is September to April, when the meat becomes a little milky. Each of the five major areas of oyster production Normandy, Brittany, the Loire, Arcachon Bay and the Mediterranean offer unique characteristics, similar to wine, they reflect their own region. Lucky for me, I will be in Arcachon to report my findings of these salty, sensuous little shellfish. There are 350 oyster farmers on the Arcachon Basin that produce 10,000 tons of oysters a year and some 60% of the oysters eaten in France come from this bay.

French menus sometimes offer a bewildering selection of oysters, whose prices differ according to their shape, size and provenance. Here’s a brief guide to some of the terms you are likely to come across:

PLATES France produces two types of oysters, plates and creuses. The plates are flatter in shape and are also known as Belons or Marennes, two of the locales that produce them. They are difficult to grow and produced in small quantities, thus more expensive.
CREUSES Also called portugaises or japonaises, these oysters have a convex shell.
NUMBERS Oysters are calibrated from 000 to 6 (equivalent to 120 to 20 grams), with the smaller number indicating the larger-sized oyster.
BOUDEUSES weigh just an ounce. Their name means “pouter” because they just pout in a corner and refuse to grow. Long too small to be commercially viable, they are now a desirable novelty.
PAPILLONS Another small oyster, weighing about 30 grams.
FINES Determined by a complicated calculation (don’t ask), this official designation means small- to medium-sized.
SPECIALES Labeled according to the same calculation as the fines, these oysters are a bit larger and more fleshy.
FINES DE CLAIRE At 20 to the square yard, these oysters mature for two months in salty claires, or marshes, where they filter nutrient-rich water that sometimes turns them green.
SPECIALES DE CLAIRE At 10 to the square yard, spéciales de claire mature for at least two months, which allows them to grow fatter and more substantial than fines de claire.
POUSSES EN CLAIRE Set in oyster parks with only five to the square yard, these oysters, prized by gourmets, grow for at least four months and double in weight.