This recipe was written on a lined index card and found in a large collection, date unknown. I’ve typed it below along with a scanned copy.

Latticed Blueberry Pie

Pastry for two-crust 9″ pie
2 pts. blueberries
3/4 to 1 c. sugar
1/4 c. all purpose flour
1-2 tsp. lemon juice
1 Tbsp butter or margarine

Roll out half of pastry; line 9″ pie plate and trim pastry about 1/2″ larger than rim. Fill with blueberries. Combine sugar and flour and sprinkle over berries. Sprinkle with lemon juice. Dot with butter or margarine. Roll out rest of pastry; cut into half-inch strips. Moisten edge of bottom crust. Arrange pastry strips in lattice across top of pie. Fold edge of bottom crust over ends of strips, press together and flute.

Bake in hot oven (425°F) about 45 minutes, or until crust is golden brown and filling begins to bubble.

If you’re in a hurry, buy ready-to-bake pie shells and fill with canned ready-to-use blueberry pie-filling following package directions.