Leaf mimicry

An early afternoon safari in the garden produced a comma butterfly hastily flying out of it, and a white butterfly which stayed. The white settled on a clematis, and then moved to the sweet william to feed on the flowers nectar. I realised that it was a female brimstone, those wings when closed look like leaves and are quite distinctive. When it flies it is not the bright yellow of the males, but white, and so is easily overlooked.