1/2 c. margarine
2/3 c. powdered sugar
Mix and press into pan, freeze, save some for garnish.
1 quart vanilla ice cream softened, whip with electric mixer, spread in pie shell, freeze 1 hour.
1 quart lime sherbet softened, whip and spread over vanilla layer.
Garnish with crumbs. Freeze one hour before serving. Let set 20 minutes before serving.