COXYOLVULACEAE (CONVOLVULUS FAMILY) 669 



nous albumen. Fruit a globular 2-6-seed.ed capsule. Flowers mostly sho^^7■, 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. DICHONDREAE. Carpels 2 or 4, distinct or nearly so ; styles 2, basilar. Creeping herbs. 

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



Tribe II. CONVOLVtrLEAE. Ovar>- 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-fiUform. Not twning. 



4. Ipomoea. Style undivided, mth stigma capitate or 2—S-globose. 



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



or ovate. 



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

 filiform, coiled, ^^•ithout cotyledons. 



6. Cuscuta. The only genus of the group. 



1. DICHONDRA 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 pedtmcles. Corolla small, yellowish or white. 

 (Name from 5is. double., and x<^vbpos, 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. ) — \Yet ground, 

 Ya. to Tex., near the coast. 



2. BREWERIA R. Br. 



Stjdes 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 silkj^ outside. (Named for Samuel Brewer.^ an English 

 botanist or amateur of the 18th century.) 



1. B. humistrata (Walt.) Gray. Sparsely liairy 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 ichite ; filaments hairy; styles united, 

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



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

 peduncles l-;5-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. 



0. B. Pickeringii (^L A. Curtis) Gray. Soft-pubescent or smoothish ; leaves 

 very uarroicly linear or the lowest linear-spatulate, tapering to the base, nearly 

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

 the flowers; sppals 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 southw. ; also 111., la., and south w. 



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 witli Convolvulus). 



1. E. argenteus Pursh. Many-stemmed fn)m a somewhat woody base, dwarf, 

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



