3. CONVÓLVULUS, Tourn. Bindweed.

Corolla funnel-form to campanulate. Stamens included. Style undivided or 2-cleft only at the apex; stigmas 2, linear-filiform to subulate or ovate. Capsule globose, 2-celled, or imperfectly 4-celled by spurious partitions between the 2 seeds, or by abortion 1-celled, mostly 2–4-valved.—Herbs or somewhat shrubby plants, either twining, erect, or prostrate. (Name from convolvo, to entwine.)

§ 1 CALYSTÈGIA. Stigmas oval to oblong; calyx enclosed in 2 broad leafy brats.

1 C. spithamæ̀us, L. Downy; stem low and mostly simple, upright or ascending (6–12´ long); leaves oblong, with or without a heart-shaped or auricled base; corolla white (2´ long); stigmas oval. (Calystegia spithamæa, Pursh.)—Dry and sandy or rocky soil; not rare.

2. C. sèpium, L. (Hedge Bindweed.) Glabrous, or more or less pubescent; stem twining or sometimes trailing extensively; leaves triangular-halberd-shaped or arrow-shaped, acute or pointed, the basal lobes obliquely truncate and often somewhat toothed or sinuate-lobed; peduncles 4-angled; bracts commonly acute; corolla white or tinged with rose-color (1½–2´ long). (Calystegia sepium, R. Br.)—Moist alluvial soil, or along streams; N. Atlantic States and westward. (Eu., etc.)

Var. Americànus, Sims. Glabrous; corolla pink or rose-purple; bracts obtuse. (C. sepium of Am. authors mainly.)—Common, across the continent.

Var. rèpens, Gray. More or less pubescent; sterile and sometimes flowering stems extensively prostrate; leaves more narrowly sagittate or cordate, the basal lobes commonly obtuse or rounded and entire; corolla from almost white to rose-color; bracts very obtuse or acute. (Calystegia sepium, var. pubescens, Gray.)—Common.

§ 2. Stigmas filiform; no bracts at or near the base of the calyx.

C. arvénsis, L. (Bindweed.) Perennial; stem procumbent or twining, and low; leaves ovate-oblong, arrow-shaped, with the lobes at the base acute; peduncles mostly 1-flowered; bracts minute, remote; corolla (9´´ long) white or tinged with reddish.—Old fields, N. Atlantic States. (Eu.)

4. BREWÈRIA, R. Br.