Common blue violet (Viola sororia )

Member of the Violaceae (Violet) family.  Grows in damp woods, meadows, 3 - 8 inches, March - June.  Smooth; 2 lateral petals bearded, lower petal longer, unbearded; all 3 lower petals strongly veined.  Leafstalks often longer than flower stalks, sometimes downy.  The flower is dark violet in color and is held above the foliage on its own stem. 

To learn more about Common blue violet, visit its profile at the USDA Plants Database