Eastern False Rue Anemone (Enemion biternatum)

3/27/12 Shades Park, IN

ID request from Sieglind - "Eastern" because it appears that there's a Western version that's a diff. species.

http://www.illinoiswildflowers.info/woodland/plants/fs_anemone.htm
and
http://plants.usda.gov/java/profile?symbol=ENBI&photoID=isbi2_001_avd.tif
see also:
http://www.wildflower.org/plants/result.php?id_plant=ENBI
"...may be confused with Rue Anemone (Thalictrum thalictroides)"
Rue Anemone has "opposite or whorled stem leaves just below the flowers,
5-10 petal-like sepals, and fruit with one seed."

and
http://eol.org/pages/594827/overview