Winter Aconite

Any of several low Eurasian perennial herbs (genus Eranthis, especially E. hyemalis) of the buttercup family Buttercup Family (Ranunculaceae) with solitary yellow or white flowers which often bloom through the snow.

I love this flower. Although it spreads and is working it's way into my lawn, the leaves die back after the bloom has gone, just about the time the grass needs its first mowing. I won't see it again until next year.