Cyperaceae - Cyperaceae

Japanese: カヤツリグサ科 - カヤツリグサか（英語表記）Cyperaceae

A family of monocotyledonous plants in the Cyperales order. They are found in almost every environmental condition, from the tropical to the frigid, and from extremely arid to wetlands, all over the world, with about 4,000 species in 90 genera. They are perennial plants with linear leaves similar to those of the grass family, but unlike the grass family, their stems are solid (most are hollow in the grass family) and their leaves are arranged in three rows (two rows in the grass family). This often results in a triangular cross section of the stem. Many species have well-developed rhizomes. Several flowers are gathered together to form a "spikelet," and many of these spikelets are gathered together to form an inflorescence. The individual flowers are small and vary from those with no perianth at all (such as the Cyperus genus) to those with six needle-like perianths. There are 1-3 stamens and 1 pistil, but some are bisexual flowers that share both (such as Eleocharis ), while others are unisexual flowers with separate male and female flowers (such as Carex ). In both cases, they are wind-pollinated. In Carex, the pistils of the female flowers are covered by hard, vase-shaped sacs (fruit sacs). Carex has nearly half the number of species in the Cyperaceae family, and with about 200 species known in Japan alone, it is the genus with the largest number of species of any seed plant. In English, herbs in the Poaceae family are called grasses, while plants in the Cyperaceae family are called sedges.

Source: Encyclopaedia Britannica Concise Encyclopedia About Encyclopaedia Britannica Concise Encyclopedia Information

Japanese:

単子葉植物カヤツリグサ目の1科。全世界の熱帯から寒帯まで，また，極端な乾燥地から水湿地にいたるほとんどあらゆる環境条件に分布し，約 90属 4000種が知られる。イネ科植物に似た，線状の葉をもつ多年草であるが，イネ科と違って茎は中実 (イネ科ではほとんどが中空) で，葉は3列 (イネ科では2列) に並ぶ。このため茎の断面が三角形になる場合が多い。根茎が発達するものも多い。花は数個ずつ集って「小穂」をつくり，この小穂がさらに多数集って花序をなす。個々の花は小さく，花被をまったくもたないもの (カヤツリグサ属 Cyperusなど) から，花被が6本の針状になったものまでさまざまである。おしべは1～3本，めしべは1本であるが，両者を共有する両性花 (ハリイ属 Eleocharisなど) と，雌雄花が別々な単性花 (スゲ属 Carexなど) とがある。いずれの場合も風媒花である。スゲ属では雌花のめしべを壺形の硬い袋 (果胞) がおおっている。スゲ属はカヤツリグサ科全体の半分近くの種数があり，日本だけでも約 200種が知られ，種子植物で最大種数をもつ属である。なお，英語ではイネ科の草本を grassというのに対し，カヤツリグサ科の植物は sedgeと呼ぶ。

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