Fls 4-5(-7)-merous, trimorphic, the styles and stamens of 3 possible lengths, anyone fl with 8 or 10 stamens alternately of 2 lengths; hypanthium hemispheric or broadly campanulate; sep short, triangular, alternating with longer, linear appendages; pet conspicuous, narrowed at the base; disk none; capsule subglobose, 3(-5)- locular, loculicidal. Monospecific.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.