Yellow or Blue?

The yellow didn't stop so it has to be the 'blue' today.

So what was the yellow?
I cannot be sure, but a large yellow butterfly came from behind and overtook me on a woodland track only to disappear round a corner ahead. When I reached the corner, it was nowhere to be seen. Two possibilities: Brimstone or Clouded Yellow.
Records of brimstones are rare in Fife so I would tend to favour a migrant clouded yellow. We will never know for sure without any photographic evidence.

The 'blue' is a female 'common blue', Polyommatus icarus, that I found at the edge of a meadow that was teeming with ringlets. Common blues can hardly be called 'common' in Fife as they are few and far between but they ARE the commonest blue encountered here.

Another view in the 'extra'.