圆叶薄荷 yuan ye bo he

Herbs perennial, rhizomatous, stoloniferous. Stems erect, 30-80 cm, striate, crisped villous, pyramidally branched. Leaves usually sessile, circular to oblong-ovate, 2-4.5 × 1.5-3 cm, villous, base cordate, margin crenate or crenate-serrate, apex obtuse. Verticillasters in terminal, dense cylindric spikes 2-4 × ca. 0.6 cm, lower 1 or 2 ± widely spaced; bracts lanceolate, ca. 3 mm, crisped. Pedicel ca. 1 mm, glabrous. Calyx broadly campanulate, ca. 2.5 mm, pubescent, subglobose, dilated in fruit, not constricted at throat, obscurely veined; teeth lanceolate-subulate, ca. 1 mm. Corolla white, purplish, bluish or purple, ca. 2.5 mm, glabrous, tube ca. 1.5 mm; lobes subequal, upper emarginate. Ovary glabrous. Nutlets unknown.

Beijing Shi, Kunming Shi, Nanjing Shi, Shanghai Shi, Yunnan (Lijiang Xian) [Europe]

Cultivated in China.

Mostl widely known as Mentha rotundifolia (Linnaeus) Hudson, but the holotype of that species has been shown to be a different plant of hybrid origin.