Ornithogalum umbellatum (Liliaceae) - This member of the lily family is native to Europe. One book I have says that it is poisonous. Another says that cooking or drying it makes it edible, and that very close relatives are used as food sources in other parts of the world.
I wouldn't try it, though. Star-of-Bethlehem blooms in mid-spring. (Photographed in PA)