Shrub with gray-brown branches, the young branchlets glabrous or with 2 longitudinal lines of hairs; leaves obovate-elliptic, 6-10 cm. long, 3-6 cm. wide, abruptly acuminate, acute at base, slighdy lustrous and nearly glabrous above, short pilose on nerves beneath, the petioles about 1 cm. long, nearly glabrous; flowers 2 or 3 in leaf axils, often short-pedunculate; ovary glabrous or scattered hairy; calyx-segments broadly linear, slighdy pilose; corolla white, reddish with age, the tube gradually ampliate on upper half, essentially glabrous; style exserted.

May-June.

Honshu, Shikoku, Kyushu.

var. rosea (Makino) Hara.

Leaves longer, acute; calyx-lobes longer, more densely pilose; corolla reddish. Honshu (centr. distr.).

f. fujisanensis (Makino) Hara. Corolla white, becoming reddish with age.