Sometimes this plant is called toothwort. The current botanical name of this plant is Cardamine concatenata. The picture was also taken April 16, 2008 in the Scifres-Maier Woods of the Celery Bog Park. It's a common spring wildflower in these woods.

http://en.wikipedia.org/wiki/Cardamine_concatenata


Some wildflower guides call it by its synonym, Dentaria lacinata, it's the same plant.