CONVOLVULACEAE (CONVOLVULUS FAMILY) 669 



nous albumen. Fruit a globular 2-6-seeded capsule. Flowers mostly showy, on 

 axillary peduncles; pedicels articulated, often 2-bracted. Many are cultivated 

 for ornament, and one, the Sweet Potato, for its edible farinaceous roots ; those 

 of several species are carthartic, e.g. Jalap. 



Tribe I. DICH6NDREAE. Carpels 2 or 4, distinct or nearly so ; styles 2, basilar. Creeping herbs. 



1 . Dichondra. Corolla deeply 5-cleft. Pistils 2, one-seeded. 



Tribe II. CONVOLVtLEAE. Ovary entire. Leafy plants, mostly twiners. 



2. Breweria. Style 2-cleft or 2-divided ; the divisions simple ; stigmas capitate. 



3. Evolvulus. Styles 2, each 2-cleft ; stigmas linear-filiform. Not twining. 



4. Ipomoea. Style undivided, with stigma capitate or 2-3-globose. 



5. Convolvulus. Style undivided or 2-cleft only at apex ; stigmas 2, linear-filiform to subulate 



or ovate. 



Tribe III. CUSCtJTEAE. Ovary entire. Leafless parasitic twining herbs, never green. Embryo 

 filiform, coiled, without cotyledons. 



6. Cuscuta. The only genus of the group. 



1. DICH6NDRA Forst. 



Calyx 5-parted. Corolla broadly bell-shaped. Stamens included. Styles, 

 ovaries, and utricular 1-2-seeded capsules 2, distinct. Stigmas thick. Small 

 and creeping perennial herbs, soft-pubescent, with kidney-shaped entire leaves, 

 and axillary 1-flowered bractless peduncles. Corolla small, yellowish or white. 

 (Name from 5/s, double, and x^Spos, a grain, from the fruit.) 



1. D. repens Forst. Leaves round-kidney-shaped, pubescent, green both 

 sides ; corolla not exceeding the calyx. (Z>. evolvvlacea Britton. ) Wet ground, 

 Va. to Tex., near the coast. 



2. BREWERIA R. Br. 



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

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

 nial 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 (Walt.) Gray. Sparsely 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 ; filaments hairy; styles united 

 at base. Dry pine barrens, Va. to La. 



2. B. aquatica (Walt.) Gray. Minutely soft-downy and somewhat hoary; 

 peduncles 1-3-flowered ; sepals silky ; corolla pink or purple ; filaments smooth ; 

 styles almost distinct ; otherwise nearly as no. 1. Wet pine barrens and margins 

 of ponds, N. C. to Tex., extending into Mo. 



3. B. Pickeringii (M. A. Curtis) Gray. Soft-pubescent or smoothish ; leaves 

 very narrowly 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; filaments (scarcely hairy) and styles (united far 

 above the middle} exserted from the open white corolla. Dry pine barrens and 

 prairies, N. J., and south w. ; also 111., la., and southw. 



3. EV6LVULUS L. 



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

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

 Low and small herbs or suffrutescent plants, mostly diffuse, never twining 

 (hence the name, from evolvere, to unroll, in contrast with Convolvulus). 



1. E. arg6nteus Pursh. Many-stemmed from a somewhat woody base, dwarf, 

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



