Robinson and Greenman misidentify this collection and Meehan (1898: 32) reports it as Aster oreganus (Nutt.) Torr. & A. Gray (Fl. N. Amer. 2: 163. 1841), a name now considered a synonym of A. subspicatus Lindl. (in Hooker, Fl. Bor.-Amer. 2: 11. 1834). The sheet was annotated subsequently by Erica Armstrong as A. oregonensis (Nutt.) Cronquist (in Univ. Wash. Publ. Biol. 17(5): 91. 1955), which is a totally unrelated taxon more properly called Seriocarpus oregonensis Nutt. (in Trans. APS., Ser. II, 7: 302. 1840). Cutright (1969: 403) also confused A. oreganus with A. oregonensis. Eaton's aster is fairly common along the Snake River in Washington where the plant was gathered in October 1805. The expedition traveled along the Snake from 11 Oct until 20 Oct (Moulton, 1988: 261-313). The name A. eatonii may be replaced as ongoing research is demonstrating that Aster should be divided into several small genera. The combination, Symphyotrichum eatonii (A. Gray) Nesom (in Phytologia 82: 283. 1998), recently has been proposed. (The Lewis & Clark Herbarium Digital Imagery Study Set, ANSP, 2002) On deposit at the Academy of Natural Sciences, Philadelphia Collected by:Meriwether Lewis & William Clark Collection date:10/01/1805