In a large saucepan combine pitted seagrapes with the beef broth and salt and pepper to taste. Bring to boil; reduce heat.

Cover the saucepan and simmer over low heat for about 1 hour or longer, until the fruit is tender. Cool the mixture and liquefy in a blender; add a little rum. Refrigerate and  serve in chilled cups with a sprig washed raw seagrapes.

Note: Seagrape the fruit, which ripens in the fall, is purple-red with velvety skin and grows wild along sea shores in warm areas. Use seagrapes when they have just turned purple.