Timing is everything. Last Thursday, a cool spring day, in northwestern Philadelphia, things were just on the cusp. These Sanguinaria canadensis, bloodroot, were waiting for the sun.
These Trilliums, too.
Ah, but look carefully! Thalictrum thalictroides, rue anemone.
Cardamine concatenata, the cutleaved toothwort, crow’s toes, pepper root or purple-flowered toothwort.
The sun did come out in the afternoon… Stylophorum diphyllum, celandine-poppy.
(Somewhat tentative ID on the the Thalictrum and Cardamine.)
Backyard and Beyond 
Thalictrum and Cardamine IDs look good to me.
Thank you!