One crab, pull off the sand bag and the shaggy substance from the sides, being careful to save the fat which is on the bottom and the sides of the shell. Chop the meat fine, season with a speck of cayenne, salt and pepper, two tablespoons of melted butter, one tablespoon of sherry, one beaten egg, two tablespoons of cream, a grating of nutmeg, one saltspoon of mustard. If not soft enough add more cream. Fill a crab shell, or small shells that can be had for this purpose. Cover with bread crumbs, squeeze on a little lemon juice, put bits of butter on top, and brown in a quick oven. If the flavor of garlic or onion is desired, rub on the shells before putting in the mixture. Serve on a bed of parsley or water-cresses, with a slice of lemon on each shell.