White Letter day

Just as we sat down for a drink after a day's work in the garden, we saw this White Letter Hairstreak on the Golden Rod, one I've never seen before.  It gets it's name from the thin 'w' on the underside of the wings, and its Latin name is the unusual Satyrium w-album.  Its life cycle is dependant on elm trees, so it became much scarcer after Dutch Elm Disease killed so many trees, but now it seems to be increasing in numbers and in range.