This section is from the book "An Illustrated Flora Of The Northern United States, Canada And The British Possessions Vol3", by Nathaniel Lord Britton, Addison Brown. Also available from Amazon: An Illustrated Flora of the Northern United States, Canada and the British Possessions. 3 Volume Set..
[Balduina Nutt. Gen. 2: 175. 1818. Not Baldwinia Raf. F. 1818.] Perennial, caulescent, simple or branched, erect herbs, with alternate entire narrow punctate leaves, and large terminal heads of both tubular and radiate, yellow flowers, or those of the disk purple. Involucre hemispheric, its small bracts imbricated in several series, appressed, or with spreading tips, the outer shorter. Receptacle convex, deeply honey-combed, chaffy, the persistent chaff coriaceous or cartilaginous, laterally united, subtending the disk-flowers. Rays large, neutral, toothed. Disk-flowers perfect, fertile, the corolla 5-toothed. Anthers sagittate at the base. Style-branches with truncate subulate tips. Achenes turbinate, silky-villous. Pappus of 7-12 scarious nearly equal scales. [Greek, perhaps referring to the immersion of the achenes in the honeycombed receptacle.]
Two known species, natives of the southwestern United States. Type species: Balduina uni-flora Nutt.
Balduina uniflora Nutt. Gen. 2: 175. 1818.
1897. E. uniflora Barnhart; Small, Fl. SE. U. S. 1283. 1903.
Stem stout, puberulent, simple, or with a few erect branches, 1°-3° high. Leaves thick, spatulate-linear or the upper linear, sessile, erect or ascending, 1'-2' long, the lower 2"-3" wide; heads long-peduncled, solitary, 2' - 21/2' broad; bracts of the involucre ovate, acuminate, thick, their tips at length spreading; rays 20-30, cuneate, 3-4-toothed at the truncate apex; disk 8"-12" broad; chaff of the receptacle cuneate, truncate, very cartilaginous, more or less united laterally, the summit eroded; achenes obconic; pappus of 7-9 oblong scales about as long as the achene.