Shellfish are highly decorative items in their own right: the color of a lobster, let alone its complex structure, would be hard to dream up, and even the humble shrimp is made handsome by its whiskers and curly tail. Whether they are served hot or cold, lobster shells, split lengthwise, form a natural container for stuffing. Smaller crustaceans such as prawns, shrimp and crayfish, preferably with their heads left on, adorn the edge of fish dishes and peep temptingly over the rim of a bowl of soup. In salads, shellfish add to the appearance as well as to the taste of the dish.