Preheat the oven to 375°F Butter an 10 x 8-inch baking dish.
To prepare filling, combine peaches, sugar, flour and lemon juice in a large bowl. Use your hands to mix it well so no little flour remain. Spread fruit mixture evenly in pan.
To prepare topping, combine flour, cornmeal sugar and salt in a medium bowl. Using your fingers or the paddle attachment of a mixer, work butter into ingredients so the mixture until mixture resembles coarse crumbs. Mix in pint nuts.
Cover evenly with topping. Set pan on a baking sheet to catch any juices that spill over. Bake 45 minutes, or until the filling is bubbling and tender to a fork and the topping is golden in color.