And within the Corianic villi, we have the tiny blood capillaries that belong to the circulatory system of that fetus. Now, these entire Corianic villi are found inside a pool of maternal blood. And that pool of maternal blood essentially oozes out of these maternal blood vessels that are found in close proximity. So remember, when the placenta was actually developed, the Corian released these digestive enzymes that digested tiny holes inside these maternal blood vessels. And those holes essentially allow the blood to actually leak out. So the way that the exchange takes place is within the maternal blood.