Cat's-eye plant - Cat's-eye plant

A perennial plant of the Saxifragaceae family (APG classification: Saxifragaceae). It is pale green, glabrous, and weak. The rhizome creeps horizontally, and the flower stalk is erect with opposite leaves. The leaves are broadly ovate, with 3-8 pairs of inwardly curved blunt sawtooth on the edge. The upper part of the flower stalk is densely covered with bracts of almost the same shape as the stem leaves, often yellowish. The flowers are surrounded by bracts and form dense cymes. The flowers have no petals, but have four calyx lobes and four stamens. The calyx lobes are pale yellow, oval, rounded at the tip, concave on the inside, and erect during flowering. The stamens are attached to the base of the calyx lobes and are shorter than the calyx lobes. The ovary is inferior and consists of two carpels, and many ovules are attached to the lateral placenta. The capsule splits at the top to reveal many seeds, which resemble the eyes of a cat with their pupils closed during the day, hence the name Nekonome-sou. The seeds are shiny brown with tiny papillae all over. They grow in clusters in mountain wetlands and puddles, and sometimes even in rice paddies, and are widely distributed in the southern Kuril Islands, Hokkaido, Honshu, Shikoku, and northern Kyushu.

[Michio Wakabayashi March 18, 2020]

Source: Shogakukan Encyclopedia Nipponica About Encyclopedia Nipponica Information | Legend

ユキノシタ科（APG分類：ユキノシタ科）の多年草。全体に淡緑色で無毛、水気が多く軟弱である。根茎は横に長くはい、花茎は立ち上がって葉を対生する。葉は広卵形で、縁(へり)に3～8対の内曲した鈍い鋸歯(きょし)がある。花茎の上部に茎葉とほぼ同形の包葉が密につき、しばしば黄色を帯びる。花は包葉に包まれ、密な集散花序をつくる。花には花弁はなく、4個の萼(がく)裂片と4個の雄しべがある。萼裂片は淡黄色、卵円形で先は丸く、内面はくぼみ、花期に直立する。雄しべは萼裂片の基部につき、萼裂片より短い。子房は下位、2心皮からなり、側膜胎座に多くの胚珠(はいしゅ)をつける。蒴果(さくか)は上部が裂けて多くの種子をのぞかせるが、この果実のようすが瞳孔(どうこう)を閉じた昼間のネコの目に似ているというので、ネコノメソウの名がある。種子は茶褐色で光沢があり、一面に微細な乳頭状突起がある。山地の湿地や水たまり、ときには水田にも群生し、南千島、北海道、本州、四国、九州北部に広く分布する。

［若林三千男　2020年3月18日］

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