Plum Pie in a Bag

Remove seed from plums; cut each half crosswise. Combine with sugar, flour, salt and nutmeg; mix well and ladle into pastry shell. Add lemon juice. For topping, cut butter into dry ingredients, cutting mixture to size of small peas. Use pastry blender or 2 knives. Sprinkle over filling to cover top. (This is rounded up but will settle as plums cook). Slip pie into heavy brown paper bag. Cover pie loosely. Fold bag end over twice and fasten with paper clips. Place on a large cookie sheet and center in oven not touching top or sides of oven. Bake at 425F for one hour.