1. Wash the trout briefly under cold running water and pat them completely dry inside and out with paper towels. Sprinkle the cavities and skins of the fish evenly with the salt and pepper.
2. Mix the cornmeal and flour together in a large bowl. In a heavy 12-inch skillet, melt the butter with the oil over moderate heat.
3. When the foam begins to subside, roll each trout over in the cornmeal-and-flour mixture, shake off the excess coating, and place the fish in the skillet.
4. Fry them for 4 to 5 minutes on each side, or until they are golden brown and crisp, and feel firm when prodded gently with a finger.
5. Arrange the trout attractively on a heated platter and serve them at once, accompanied by the lemon wedges.
