370 coNVOLvuLACE^:. (convolvulus family.) 



Var. repens, Gray. More or less pubescent ; sterile and sometimes 

 flowering stems extensively prostrate ; leaves more narrowly sagittate or cor- 

 date, 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, Graij.) — Common. 



§ 2. Siigmas fdiform ; no bracts at or near the base of the cali/x. 



C. ARVENSis, 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) Avhite 

 or tinged with reddish. — Old fields, N. Atlantic States. (Eu.) 



4. BKEWERIA, II. Br. 



Styles 2, or rarely 3, simple and distinct, or else united into one below ; 

 stigmas depressed-capitate. Otherwise as Convolvulus and Evolvulus. — 

 Perennial prostrate or diffusely spreading herbs ; flowers small ; in summer ; 

 corolla more or less hairy or silky outside. (Named for Samuel Brewer, an 

 English botanist or amateur of the 18th century.) 



1. B. humistrata, Gray. Sparselj hairy or nearly smooth; leaves 

 varying from oblong with a somewhat heart-shaped base to linear, mucronate 

 or emarginate ; peduncles 1 - 7-flowered ; bracts shorter than the pedicels ; 

 sepals pointed, glabrous or nearly so; corolla white; Jilaments hairy ; styles 

 united at base. (Bouamia humistrata, Gray.) — Dry pine barrens, Va. to La. 



2. B. aquatica, Gray. Minutely soft </oif?K_y and somewhat hoary; pe- 

 duncles 1 -3-flowered; sepals silky ; corolla pink or purple; Jilaments smooth; 

 styles (ihnost distinct; otherwise nearly as n. 1. (Bouamia aquatica. Gray.) — 

 Wet pine barrens and margins of ponds, N. C. to Tex., extending into Mo. 



3. B. Pickeringii, Gray. Soft-pubescent or smoothish; leaves very 

 mirroich/ linear or the lowest linear-spatulate, tapering to the base, nearly 

 sessile ; peduncles 1 -3-flowered ; bracts resembling the leaves, mostly exceeding 

 the flowers; sepals hairy ; Jilanients,{sQaTce\yha,ivy) and styles (united far 

 above the middle) exserted from the open ivhite corolla. (Bouamia Pickeringii^ 

 Qray.) — Dry pine barrens and prairies, N. J. and southward ; also W. 111. 



5. EVOLVULUS, L. 



Calyx of 5 sepals, naked at base. Corolla open funnel-form or almost ro- 

 tate. Styles 2, each 2-cleft ; stigmas obtuse. Capsule 2-celled ; the cells 

 2-seeded. — Low and small herbs or suffrutescent plants, mostly diffuse, never 

 tw^ining (hence the name, from evolvo, to unroll, in contrast with Convolvulus). 



1. E. argenteus, Pursh. Many-stemmed from a somewhat woody base, 

 dwarf, silky-villous all over ; leaves crowded, broadly lanceolate, sessile, or the 

 lower oblong-spatulate and short-petioled, about h' long ; flowers almost ses- 

 sile in the axils ; corolla purple, 3" broad. — Sterile plains and prairies, Dak. 

 and Neb. to Mo. and Tex. 



6. CUSCUTA, Tourn. Dodder. 



Calyx 5- (rarely 4-) cleft, or of 5 sepals. Corolla globular-urn-shaped, bell- 

 shaped, or short-tubular, the spreading border 5- (rarely 4-) cleft, imbricate. 

 Stamens with a scale-like often fringed appendage at base. Ovary 2-celled, 



