Twinleaf (Jeffersonia diphylla)
Hawk Mtn., PA (May 13, 2006)
http://plants.usda.gov/java/profile?symbol=JEDI&photoID=jedi_004_ahp.tif
http://www.fs.fed.us/wildflowers/plant-of-the-week/jeffersonia_diphylla.shtml
https://www.minnesotawildflowers.info/flower/twinleaf
There is another plant with a similar "twin leaf" look, Epimedium:
http://awaytogarden.com/a-plant-id-order-jeffersonia-diphylla/