Cut the plums in half; Discard pits. Divide equally between four well- greased 6 oz. custard cups. In a bowl, combine the flour, sugar, salt and nutmeg; cut in butter until mixture is crumbly. Stir in cornflakes; sprinkle over plums. Bake at 350 degrees for 40 minutes or until the topping is golden brown. Serve warm with cream if desired.