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''Roscoea humeana'' is a perennial herbaceous plant occurring in the Sichuan and Yunnan provinces of China.〔 Most members of the ginger family (Zingiberaceae), to which it belongs, are tropical, but ''R. humeana'', like other species of ''Roscoea'', grows in much colder mountainous regions.〔 It is sometimes grown as an ornamental plant in gardens.〔 ==Description== ''Roscoea humeana'' is a perennial herbaceous plant. Like all members of the genus ''Roscoea'', it dies back each year to a short vertical rhizome, to which are attached the tuberous roots. When growth begins again, "pseudostems" are produced: structures which resemble stems but are actually formed from the tightly wrapped bases (sheaths) of its leaves.〔 In the case of ''R. humeana'', the flowers appear before the leaves are fully grown. Plants are usually 13–25 cm tall, with four to six leaves. Each leaf has a small ligule, extending to about 2 mm. The blade of the leaf (the part free from the pseudostem) is usually 10–30 cm long by 3–6 cm wide. The leaf sheath is smooth (glabrous), tapering to a point.〔 In its native habitats, ''R. humeana'' flowers between April and July. The stem (peduncle) of the flower spike is hidden by the leaf sheaths. One to many flowers open together and may be of various colours: purple, violet, yellow, pink or white. The bracts which subtend the flowers are shorter than the calyx.〔 Each flower has the typical structure for ''Roscoea'' (see the diagrams in that article). There is a long tube-shaped outer calyx, 10–14 cm long with a two-lobed apex. Next the three petals (the corolla) form a tube slightly longer than the calyx, terminating in three lobes, an upright hooded central lobe, 3–4 cm long by 2.5–3 cm wide, and two slightly smaller side lobes, 3–3.5 cm long by about 1.5 cm wide. Inside the petals are structures formed from four sterile stamens (staminodes): two lateral staminodes form what appear to be small upright petals, which are white tinged with purple and 1.5–1.7 cm long; two central staminodes are partially fused at the base to form a lip or labellum, 2–2.5 cm long by about 3 cm wide. The labellum, which is usually smaller than the upper petal, bends backwards and is usually split into two lobes; the sides are wavy.〔〔 The single functional stamen has a white anther, about 1.2 cm long, with yellowish-green 6–8 mm long spurs formed from the connective tissue between the two capsules of the anther. The ovary is clylinder-shaped, about 1 cm long, expanding to a 2.5 cm long capsule when seed is set.〔 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「Roscoea humeana」の詳細全文を読む スポンサード リンク
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