Flower:

Clusters of 2 to 9 stalked flowers at the top of the plant, whorled around upper leaf axils, and at the end of few branching stems arising from upper leaf axils. Flowers are 1/3 to ½ inch (to 12 mm) long with 4 petals fused near the base, each egg-shaped, erect but flaring out slightly at the pointed tip, and narrowing at the base forming a tubular spur half to nearly as long as the rest of the petal. Hiding inside are 4 yellow-tipped stamens. Color is light green to purple-tinged. The sepals are green, lance to egg-shaped, tapering to a pointed tip, alternating with the spurs, half to nearly as long as the petals above the spur.

Leaves and stem:

Leaves are ¾ to 2 inches (2 to 5 cm) long, ¼ to ~½ inch wide, toothless and hairless. Basal leaves are oval to spatula shaped, narrowing to a short stalk; stem leaves are more egg-shaped, broadly rounded at the base, tapering to a sharp point, strongly 3 or 5 veined, stalkless or nearly so, and widely spaced on the stem. Stems are erect, hairless, square and unbranched or few branched in the upper plant.

Fruit:

Fruit is a conical capsule that protrudes from the opening of the flower like a rhinoceros horn.

Notes:

Between the subdued flower color and green of the foliage it is a species easy to pass by in the lush undergrowth of damp woods and bogs. If you manage to notice one, suddenly you may see many around you. The unique flowers and fruits make this not likely to be confused with any other species. There are two subspecies (or vars, depending on the reference), though they are not well documented and distinguishing characteristics are unknown; subsp. brentoniana is apparently rare and limited to parts of eastern Canada, while subsp. deflexa is present across much of Canada and parts of the northern US, including Minnesota.