Here is the image location of the plant in question:

http://image53.webshots.com/53/4/37/85/428443785iuaCzM_ph.jpg

I found this plant on a riverbank in Southeastern, MA. It was an herbacious plant, perhaps about a foot tall (but certainly no taller), and I encountered it in flower during Mid-August.

Unfortunately, it was the only specimen I came across, so I decided to take a picture rather than risk killing a rare or endangered plant.

If anyone has any idea as to what this plant might be (even if you can direct me to the family or genus), I would really appreciate it. Thanks!!!