Pursh (1813: 355) and Meehan (1898: 25) apply the name Potentilla fruticosa L. (Sp. Pl.: 495. 1753) to this collection. Moulton (in press) refers to it as Pentaphylloides floribunda (Pursh) A. Löve (in Svensk Bot. Tidskr. 48: 224. 1954). Holmgren (in Cronquist et al., 1997: 75) refers both names to synonymy under Pentaphylloides fruticosa (L.) O. Schwarz (in Mitt. Thüring. Bot. Ges. 1: 105. 1949). Pentaphylloides Duhamel (Traité Arbres Arbust. 2: 99. 1755) is an illegitimate superfluous name for Potentilla L. (Sp. Pl. 495. 1753) and therefore we adopt the next available name, Dasiphora Raf. (Aut. Bot.: 167. 1840.). As here defined, the species is a circumboreal taxon with two subspecies. We anticipate the appropriate combination for North American material to be made by others in the near future. Pursh gives the location as "on the waters of the Rocky-mountains." Lewis obtained the specimens in Nevada Valley, Powell Co., Montana, on 6 Jul 1806, at "the prairy of the Knobs" (see Moulton, 1993: 93). (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:07/06/1806