National Geographic : 1986 Jan
RESPIRATION In addition to breathing through aset of lungs, freshwater turtles can use their mouth cavity in gill-like fashion. Water is drawn through the nostrils,oxygen absorbed in the mouth cavity, and the water expelled. Some species can absorb oxygen through two thin-walledsacs located near the cloacal opening. A few turtles can absorb small amounts of oxygen through their skinduring hibernation.