Coquilles St. Jacques is the French term for "scallops".

Literally, "St. James' Shells".

The story goes that as the boat carrying the body of St. James (St. Jacques, en Français), a fisherman who became an apostle, was approaching the coast of Spain, a horse suddenly raced into the water, taking the horseman with it to certain death. But instead of drowning, they were miraculously raised to the surface, covered in scallop shells.

Scallop shells became associated with those who had made the pilgrimage to the shrine of St. James, the patron saint of pilgrims.