The Canadian Tiger Swallowtails Papilio canadensis- I think these are the largest butterflies, locally, and one of the showiest, appeared a week or so back. Like a lot of butterflies, it seems, initially they are more- hyperactive? skittish? in any case, near impossible to photograph as they zip about! Now they've settled down a bit, and never more so than when feeding on Lilac flowers Syringa vulgaris. Though they will also happily feed on everything from native Honeysuckles just coming into bloom to Dandelions, they seem to spend the most time (allowing some chance for photos) on Lilacs.