Dottie - When I saw your request, two things came immediately to mind. One is that your mom may not remember the pie the way it actually was and the second was a recipe that I've just recently seen for a pie that uses lemon slices. I'm going to include that. Another thought that came to me while typing in this is that it may have been a lemon chiffon pie in a cookie crust. Could your mother do a little describing of the pie. I've learned that recipes go by very different names in different parts of the country.

Here's the recipe:
Ohio Lemon Pie - originally an early Ohio Shaker recipe
2 lemons
2 cups granulated sugar
5 eggs
1/4 tsp. salt
Pastry for a double crust pie

Wash lemons well and cut off ends. Place lemons on a cutting board over a bowl to catch the juices. With a knife, slice into paper-thin slices. (A food processor won't slice them thin enough.) Combine lemon slices and juice with sugar in a bowl and let stand at room temperature for at least 2 hours or overnight. Beat eggs with salt in a small bowl and stir in lemon mixture.

Roll out half of the pastry and fit into a 9-inch pie pan. Roll out second half of pastry and cut slits to allow steam to escape. Pour filling into pastry-lined pan and top with second crust. Trim and flute edge.

Bake in a 425-deg. F. oven for 15 minutes. Reduce heat to 350-deg. F. and bake 30 to 40 minutes more, or until pastry is golden and knife inserted in vent hole comes out clean.

From Sue Dawson of the Columbus Dispatch