sea cucumber a mysterious creature which belongs to the class Holothurians. These creatures are quite distinct from fish, crustaceans, and molluscs. There are a lot of them (over 600 species) and they occur all round the world, but only a few species are used as food and only in some regions, notably the Orient (where the principal markets are at Hong Kong, which is by far the most important, and in Korea, Singapore, and Malaysia) but in recent times also in Barcelona and its environs, and to a small extent in Provence and elsewhere in the Mediterranean, e.g. Istanbul.
