will be about 2 1/2 cups. Lightly oil a 6 cup gratin dish.Add mushrooms to the pasta. Pour half the sauce over the pasta mixture.Mix well.Scrape into gratin dish and pat linguine into a smooth layer.Gently, mix remaining sauce with crabmeat and spoon over the linguine. Sprinkle bread crumbs over top.Bake for 15 minutes or until thoroughly heated through.If the top has not browned,slip under the broiler for a brief minute.Serve directly from gratin dish. Serves 4.