“Tuney, look at this. Watch what I can do.”
Lily had picked up a fallen flower from the bush behind which Snape lurked. Petunia advanced, evidently torn between curiosity and disapproval. Lily waited until Petunia was near enough to have a clear view, then held out her palm. The flower sat there, opening and closing its petals, like some bizarre, many-lipped oyster.
-Harry Potter and the Deathly Hallows, pg 663-664, US Edition