Now, this sears membrane consists of two individual membranes. We have an outer membrane and we have an inner membrane. So this is a two layer protective barrier that encloses our lungs. So to see what we mean, let's take a look at the following simplified diagram of the lungs and our membrane. Now, this entire membrane that encloses our lungs is known as aroplora. So we have an outer membrane of the pleura, known as the parietal pleura.