The yellow, fragrant flowers of this species differ from most of the others in that the lower lip of the corolla is the larger, helmet-like, the upper being long, narrow, erect. Spur, long, curved downward. Flower-stalk stout, straight, with few or no leaves and few bladders. Leaves, when they do occur, entire. Scape reaches the top of the water for flowering, 3 to 14 inches high, rooted in bogs or the muddy shores of ponds. May to September.