Clean the octopuses thoroughly, eliminate the eyes and mouth, wash them several times, and beat lightly on a work-surface to tenderize them. Put them in a pot (preferably earthenware), roomy enough to easily contain them. Add the oil and parsley, season with salt and pepper and douse with wine. Cover the pot with its lid, so that the octopuses are hermetically closed. Bake in a moderate oven, removing after a couple of hours. Put the octopuses on a serving plate and keep hot. Reduce the cooking liquid, season the octopuses, and serve.