This section is from the book "Who's Who Among The Wild Flowers", by W. I. Beecroft. Also available from Amazon: A Field Guide to Edible Wild Plants.
Viola pallens.
Violet Family. Apr. - May.
Plant 3 - 5 inches tall. Found in moist, wooded places. Common.
White with purple veins, side divisions usually bearing a small tuft of hairs, slightly fragrant.
Round heart-shaped, slightly scalloped.
Viola lanceolata.
Violet Family. Apr. - June.
Found in moist ground. Nova Scotia to Minnesota and southward.
White, purple veined, side divisions beardless.
Long, narrow, indistinctly scalloped, tapering into a long stem.
Viola canadensis.
Violet Family. May - July.
Found in woodlands, very widely-distributed, mountainous and hilly country chiefly. Easily distinguished from other white violets by its tall leafy stem 6 - 24 inches high.
White or pale lavender, violet tinged on the outside, side divisions bearded, lower one striped with fine dark lines.
Heart-shaped, pointed, toothed.
 
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