Lovely butterfly in the rosemary hedge

Yesterday, while I was taking photos of the blossoming rosemary hedges, yes they are huge hedges (!), suddenly this beautiful butterfly flitted along and landed in front of me to feast on the blossoms.

It is a Gulf fritillary and takes its name from migration north over the Gulf of Mexico. What is really fascinating is that while it has those beautiful silvery white spots on the undersides of its wings, from the dorsal view (below), it looks very different!