in War Department [U.S.], Pacif. Railr. Rep. 4(5): 90, plate 7. 1857.
Subshrubs. Stems prostrate to decumbent. Bark exfoliating in grayish or grayish brownish strips. Branches erect to decumbent; twigs with simple trichomes. Leaves marcescent, opposite; petiole absent or present; blade elliptic, ovate, or ovate-elliptic, herbaceous, margins entire or shallowly crenate-serrate, plane; venation acrodromous. Inflorescences terminal, racemes or racemose cymes, 4–12-flowered; peduncle present. Pedicels present. Flowers bisexual; perianth and androecium nearly hypogynous; hypanthium adnate to ovary proximally, free distally, hemispheric, weakly 9–11-ribbed in fruit; sepals eventually deciduous, (4–)5–6, erect, narrowly oblong or oblong-lanceolate, appressed-pubescent abaxially; petals 4–6, valvate, reflexed, white, obovate or oblong, base clawed, surfaces glabrous; stamens 8–12; filaments distinct, dorsiventrally flattened, abruptly tapered medially, apex not 2-lobed; anthers elliptic; pistil (2–)4–5-carpellate, ovary slightly inferior, (3–)4–5-locular; placentation axile; styles caducous, (3–)4–5, distinct or connate basally. Capsules depressed-spheric, cartilaginous, dehiscence basipetally septicidal, carpels separating entirely. Seeds 1 per locule, brown or reddish brown, ellipsoid, trigonous.
w United States.