Here's a site where you can compare butterfly species side by side. It was helpful in determining whether the big yellow butterfly was an Appalachian Tiger Swallowtail or an Eastern Tiger Swallowtail.
UPDATE: Bonus Sunday Great Spangled Fritillary on Bull Thistle flower pictures.
(Posted by ifthethunderdontgetya™³²®© and cross-posted at my place. Mouse over pics for captions, and click them for larger versions.)
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