Viola

...A perennial plant of the Violaceae family (illustration), commonly found in sunny fields and mountains. The Japanese name is said to be an abbreviation of "Sumiire" (ink pot), as the shape of the flower resembles a carpenter's ink pot. There is no above-ground stem, and the leaves and flower stalks grow together from the base of the plant, reaching a height of about 7-15 cm during the flowering season, and becoming slightly larger after flowering. The underground stem is short, and the leaves grow at the base. Some leaves and flower stalks are hairy, while others are not. The petiole is about the same length as the leaf blade or longer, with a pair of lanceolate stipules at the base and a narrow wing at the top. The leaf blade is oblong to triangular-lanceolate with a blunt tip during flowering, almost truncate to slightly cordate at the base, and becomes wider after flowering, almost triangular. ...

*Some of the terminology that mentions "Viola" is listed below.

Source | Heibonsha World Encyclopedia 2nd Edition | Information

…日当りのよい山野に普通なスミレ科の多年草（イラスト）。和名は花の形が大工の使う墨つぼに似ているから〈墨入れ〉の略という説がある。地上茎がなく，葉と花茎は株元から集まって出て，花期の高さ7～15cmほど，花後やや大きくなる。地下茎は短く，葉は根生する。葉や花の柄に毛があるものも，ないものもある。葉柄は葉身とほぼ同長か，より長く，基部に披針形の托葉が1対あり，上部に狭い翼がある。葉身は花期には長卵形から三角状披針形で先は鈍く，基部はほぼ切形からやや心形，花後はより幅広くなり，ほぼ三角形にまでなる。…

※「Viola」について言及している用語解説の一部を掲載しています。

出典｜株式会社平凡社世界大百科事典 第２版について | 情報