Sold in bundles of 10.

At a Glance: A delicate perennial that spreads by rhizome. A common species that is found in moist forest areas, ravines, streambanks and does well in gardens.

Leaves: All basal, numerous, long-stalked (slightly shorter than flower stems), fern-like, much divided into narrow oblong ultimate segments. 
Flowers: Pinkish-purple heart shaped base drooping flowers. Flowers have 4 petals, outer 2 each with a short sac-like spru and spreading tip. 5-15 flowers cluster at the top of a stem; flower stems have no leaves.
Height: 5-20 inches tall.

Sun/Shade Tolerance Hydrology Elevation Range
mostly shady 60%-80%
full shade > 80%
moist
low elevation
mid elevation

References:

Pojar, Jim, and Andy MacKinnon. Plants of the Pacific Northwest Coast: Washington, Oregon, British Columbia & Alaska. Revised ed. Redmond, Wash.: B.C. Ministry of Forests and Lone Pine Pub., 2004. Print.