Remove excess shell from the crabmeat. In a mixing bowl, combine cream cheese, butter, green onions, Old Bay Seasoning and horseradish. While mixing, gradually add the crabmeat. Divide the mixture into two balls. Refrigerate the balls for at least one hour. On a piece of waxed paper, mix the parsley and Old Bay Seasoning. Remove the crab balls from the refrigerator and roll them on the wax paper until they are completely coated.