In a large bowl, cream butter and sugar. Beat in eggs, one at a time. Add corn syrup, milk and vanilla; mix well. Fold in cornmeal and flour. Pour into pastry shells.
Bake for 25 minutes.
Reduce heat to 300°. Bake 20-25 minutes longer or until set (cover edges with foil during the last 15 minutes to prevent overbrowning if necessary).
Cool on a wire rack. (Garnish with whipped cream if desired.)