Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.
Genus Description - Fls 4-merous; cal with a small inner membrane across the base of each sinus, but without a continuous internal rim; cal-lobes with thin, hyaline margins, usually alternately dissimilar; cor funnelform to campanulate, without folds or plaits in the sinuses and without internal scales, but regularly with nectary glands alternating with the stamens toward the base within; ovary stipitate, the stigmas large, sessile or on a short style; ovules covering most of the inner surface of the ovary; seeds numerous, papillate (in ours) or reticulate and caudate; glabrous herbs, ours taprooted annuals or biennials, with showy, long-pedicellate fls solitary or in open, cymose infls. (Anthopogon Raf.) (Often included in Gentiana or Gentianella) 20, temp. and boreal N. Amer. and Eurasia.
gentian, fringed gentian