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''Penstemon'' ,〔''Sunset Western Garden Book,'' 1995:606–607〕 the beardtongues, is a large genus of North American and East Asian flowering plants formerly placed in the Scrophulariaceae family (Cronquist system). Due to new genetic research, it has now been placed in the vastly expanded family Plantaginaceae. They have opposite leaves, partly tube-shaped, and two-lipped flowers and seed capsules. The most distinctive feature of the genus is the prominent staminode, an infertile stamen. The staminode takes a variety of forms in the different species; while typically a long straight filament extending to the mouth of the corolla, some are longer and extremely hairy, giving the general appearance of an open mouth with a fuzzy tongue protruding and inspiring the common name beardtongue. Most penstemons are deciduous or semi-evergreen perennials, the remainder being shrubs or subshrubs. Heights can range from 10 cm to as much as 3 metres. The one Asiatic species previously treated in ''Penstemon'' is now placed in a separate genus ''Pennellianthus''. This leaves ''Penstemon'' a mostly nearctic genus, with a few neotropical species. Although widespread across North America, and found in habitats ranging from open desert to moist forests, and up to the alpine zone, they are not typically common within their range. == History == Native Americans long used penstemons as medicinal remedies for humans and animals.〔Escamilla, G., et al. (''Penstemon ambiguus''. ) Medicinal Plants of the Southwest. New Mexico State University. 2001. Updated 2008.〕 John Mitchell published the first scientific description in 1748; although he only named it as ''Penstemon'', we can identify it as ''P. laevigatus''. Linnaeus then included it in his 1753 publication, as ''Chelone pentstemon'', altering the spelling to better correspond to the notion that the name referred to the unusual fifth stamen (Greek "penta-", five). Mitchell's work was reprinted in 1769, continuing with his original spelling, and this was ultimately accepted as the official form, although ''Pentstemon'' continued in use into the 20th century. Although several more species were found in the 18th century, they continued to be classified in ''Chelone'' until about the 1820s. The period of 1810 to 1850 increased the number of known species from 4 to 63, as expeditions traveled through Mexico and the western United States, followed by another 100 up to 1900. During this time, seeds began to be offered for sale in Europe, the earliest known dating from 1813, with John Fraser offering four species in London, followed by Flanagan & Nutting offering nine species in their 1835 catalog. Subsequently many hybrids were developed in Europe. Fieldwork in the remote parts of the Great Basin during the 20th century brought the total number of species known to over 250. The genus was extensively revised by David Keck between 1932 and 1957; in 1946 the American Penstemon Society was formed to promote both horticultural and botanical interest. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Penstemon」の詳細全文を読む スポンサード リンク
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