We are a commune of inquiring, skeptical, politically centrist, capitalist, anglophile, traditionalist New England Yankee humans, humanoids, and animals with many interests beyond and above politics. Each of us has had a high-school education (or GED), but all had ADD so didn't pay attention very well, especially the dogs. Each one of us does "try my best to be just like I am," and none of us enjoys working for others, including for Maggie, from whom we receive neither a nickel nor a dime. Freedom from nags, cranks, government, do-gooders, control-freaks and idiots is all that we ask for.
The Tiger Swallowtail of the Eastern US is dimorphic. This is a dark female on wild daisies.
She will not live very long. Except for our migratory, Milkweed-loving Monarch butterflies, most do not live very long in their winged form. Much more life as caterpillars and pupae. The brief task of the winged form is to produce eggs, then die. Short, sweet, and lovely.
I believe that is a Red Spotted Purple. http://www.carolinanature.com/butterflies/rsp.html There are no tails. In the dark phase female, the black stripes of the Tiger are clearly visible in the brown. http://www.sciencephoto.com/media/128859/enlarge Note the lack of any red in the lower wings of your photo. The red spotted purple has a bit of red in the upper wings.
Kerry: Given the extensive number of white cells along the edge of the upper and lower wing margins, Bird Dog's butterfly looks like an intergrade between a white admiral and a red spotted purple, which would be consistent with Bird Dog's neighborhood. A wonderful photo! See http://bugguide.net/node/view/39878