Fritillary

A pleasant surprise (having just looked his fellow up) - a Silver Washed Fritillary.  

I've not knowingly seen one before - that said at the distance I was when taking this (chilling out with a coffee on the terrace) I'd assumed the orange fluttering was a comma butterfly and I may have made that error before.

A clearer view of the 'silver washed' underside in the extra photo.