Canada violet
Canada violet
Viola canadensis
Violet Family or Violaceae
Flowers basically white with purple veining, yellow tinges at the base of the five petals (lowest with a spur) and purplish-pink colouring on the  back of the petals. 
(Photographed at the Fletcher Wildlife
Garden -  May 26)
One of the species of violet with the leaves and flowers carried on the same stalk.
  © Pathology Images Inc. 2002 2002
Leaves alternate, heart-shaped and finely toothed.