Pick over, wash, and cook one-half peck spinach. Drain, and chop finely. Season with salt, pepper, and lemon juice, and add one tablespoon melted butter. Butter slightly small tin moulds and pack solidly with mixture. Chill, remove from moulds, and arrange on thin slices of cold boiled tongue cut in circular pieces. Garnish base of each with a wreath of parsley, and serve on top of each Sauce Tartare.