Gnetum (English spelling)

Japanese: グネツム（英語表記）Gnetum

Gnetaceae are climbing trees or shrubs of which about 30 species are known to grow in the tropical forests of Asia, Africa, and northern South America. Along with Ephedra and Welwitschia, this group is the most advanced of the gymnosperms, and has several characteristics that are ascribed to angiosperms. The most striking feature of Gnetum is that its leaves closely resemble those of dicotyledonous plants, which have the reticulate venation common to dicotyledonous plants. The vascular xylem of the stem also has vessels found in angiosperms, as in Ephedra. They are usually dioecious, and many flowers are gathered together to form a spike. The male flowers are whorled around the inflorescence axis. The female flowers are whorled in groups of 3 to 8, and each female flower contains a single ovule enclosed in a perianth. The ovule protrudes outward at the tip like a beak. The perianth of the mature fruit becomes fleshy and berry-like.

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

Japanese:

グネツム科のつる性の高木または低木で，アジア，アフリカ，南アメリカ北部の熱帯森林に 30種ほど知られている。この類はマオウやウェルウィッチアとともに裸子植物のなかで最も進んだグループで，被子植物のものとされる形質をいくつももつ。グネツムの最も著しい特徴は，葉が双子葉植物に普通な網状脈をもつ葉にきわめて類似していることである。また茎の維管束木部にはマオウ類と同じく被子植物にみられる道管がある。普通は雌雄異株で，多数の花が集って穂状花序をつくる。雄花は花序軸に輪生する。雌花は3～8ずつ輪生し，各雌花には花被に包まれた1個の胚珠がある。胚珠は先端が嘴状に外へ突き出ている。成熟した果実は花被が多肉となり液果状になる。

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