On Saturday I called in at Mill Hill hoping for a Clouded Yellow, but without any great expectation. To my amazement after a short time at the bottom of the hill I saw the unmistakable orangey-yellow form flying across the slope. I saw it five times over the next forty minutes. I flew right past me at one point and I could see its angular shape with the distinctive black border on its upperside. I also saw Meadow Browns, a Red admiral and common Blues. A buzzard soared overhead.