A pure white Bleeding-Heart that, as a plant, is just about indistinguishable from Dutchman’s Breeches (Dicentra canadensis) until it blooms. Even then, a casual glance might register as the more common Dutchman’s Breeches—and especially here on the Trillium Trail, where it was growing in the middle of a patch of Dutchman’s Breeches.
For a description of the species, see the Dicentra canadensis reference page.