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''Roscoea praecox'' is a perennial herbaceous plant occurring in the Yunnan province of China.〔 Most members of the ginger family (Zingiberaceae), to which it belongs, are tropical, but ''R. praecox'', like other species of ''Roscoea'', grows in much colder mountainous regions.〔 It is sometimes grown as an ornamental plant in gardens.〔 == Description == ''Roscoea praecox'' 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. praecox'', the flowers appear before the leaves are fully grown. Plants are usually 7–30 cm tall. The first four or five leaves consist only of a sheath, which has brownish veins. The remaining leaves, which are not developed at flowering time, have a blade, with a very small ligule at the junction of the sheath and blade.〔 In its native habitats, ''R. praecox'' flowers between April and June. The stem (peduncle) of the flower spike may either be hidden by the leaf sheaths or protrude. One to three flowers open together and may be of various colours: purple, violet or white. The bracts which subtend the flowers are 4–6.5 cm long.〔 Each flower has the typical structure for ''Roscoea'' (see the diagrams in that article). There is a tube-shaped outer calyx, 3–4.5 cm long with a two-toothed apex. Next the three petals (the corolla) form a tube only just slightly protruding from the calyx, terminating in three more or less equally sized lobes, each around 3 cm long: an upright central lobe and two side lobes. Inside the petals are structures formed from four sterile stamens (staminodes): two lateral staminodes form what appear to be small upright petals, which are rhombic in shape with a narrower base, 1.7–2.5 cm long; two central staminodes are partially fused at the base to form a lip or labellum, 2.5–4 cm long by 1.5–2 cm wide. The labellum bends backwards and is split into two lobes for more than half its length. It has white markings at its narrowed base.〔〔 The single functional stamen has a cream anther with spurs about 7 mm long, formed from the connective tissue between the two capsules of the anther.〔 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 praecox」の詳細全文を読む スポンサード リンク
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