Greater Celandine

Chelidonium majus. Thanks to BowBelle for helping me to id this - she blipped a photo of one yesterday...
Related to the poppy family, not the buttercup family like the lesser celandine. Just a couple of patches growing on the side of a wall outside one of the houses at the top of the lane.
Can't remember ever seeing one of these in Lancashire although my book says they are common there.