2. Ruellia L. 



Perennial herbs or shrubs; leaves petioled, entire to undulate or rarely dentate; 

 flowers usually large and showy, solitary or clustered in the axils or borne in 

 terminal cymose panicles; calyx usually 5-parted, the segments often narrow; 

 corolla red, yellow, white or purple (usually mauve), funnelform or salverform, 

 sometimes saccate, the tube usually narrow below, the upper portion more or less 

 campanulate, the limb of 5 obtuse spreading lobes; stamens 4. didynamous, the 

 flat to tip( 2-4 mm. wide, villous-ciliate, villous to glabrate on back; corolla 



A large genus containing upward of 200 species, a majority of which are 

 tropical or subtropical. The geographic center of distribution in the Western 

 Hemisphere is somewhere in southern Mexico or Central America. 



1. Calyx lobes linear-lanceolate, flat to the tip, 2-4 mm. wide 1. R. strepens. 



1. Calyx lobes narrowly linear, the prolonged tips very slender to almost bristle- 

 form 2. R. humilis. 



1. Ruellia strepens L. 



Stem to about 1 m. high, simple or with few ascending branches, minutely 

 pilose to glabrous; principal leaves membranaceous, ovate, rounded or tapering 

 to slender petioles at base, acuminate at apex, entire to barely undulate, to 

 18 cm. long and 9 cm. wide, short-strigillose to glabrous; peduncles borne from 

 1 to 3 median nodes, to 9 cm. long, terminated by 2 dilated leafy bracts that 

 subtend 1 to 3 showy flowers; calyx segments lanceolate to linear-lanceolate, 

 flat to tip, 2-4 mm. wide, villous-ciliate, villous to glabrate on back; corolla 

 pale-blue-violet, broadly expanding, 3-6 cm. long, with broadly funnelform 

 throat; capsule glabrous, 1-2 cm. long, usually overtopped by calyx segments. 



In rich woods, talus slopes and low woodlands, seepage areas, gravel bars and 

 floodplains, commonly in calcareous areas, in e. and n.-cen. Tex. and Okla. 

 (Cherokee and Osage cos.), Apr.-May; from Tex. to S.C., n. to N.J., Pa., O., Ind., 

 111., Mo. and Kan. 



The var. cleistantha Gray has smaller cleistogamous flowers usually in cymose 

 clusters and from several of the axils, and a peduncle lacking or shorter than 

 that of var. strepens. 



2. Ruellia humilis Nutt. 



Stem coarse to slender, usually erect or rarely decumbent at base, to 8 dm. 

 high, in clusters from knotty shortened rhizomes, often strongly 4-angled, villous- 

 hirsute with whitish hairs or glabrescent, usually with slender elongate arched- 

 ascending to horizontally divergent or reclining branches; leaves of the main axis 

 as many as 36. coriaceous, to 8 cm. long and 45 mm. wide; main leaves with 

 petioles to 3 mm. long, ovate to lanceolate or broadly elliptic, subacute to acute 

 or mostly obtuse or rounded at apex, truncate to broadly cuneate and decurrent at 

 base, entire or slightly undulate, hirsute to villous or sometimes pilose-ciliate 

 on margins; bracts lanceolate to linear-lanceolate or oblanceolate to elliptic; 

 flowers usually few in the axils of the median and upper leaves, on very short 

 peduncles; calyx lobes linear-attenuate, 15-25 mm. long, villous-hirsute and 

 conspicuously ciliolate; corolla lavender to light-blue, 3-7 cm. long, the tube 

 to 45 mm. long, the limb mostly 2 to rarely 4 cm. broad, in cleistogamous flowers 

 the reduced corolla is tubular and closed; capsule brownish, to 15 mm. long and 

 5 mm. broad, glabrous, constricted at base; seeds few, ovate to suborbicular, 

 3 mm. in diameter. R. ciliosa of auth. 



In open forests, savannahs and old fields, edge of streams and in mud about 

 lakes and ponds, primarily in e. fourth of Tex., rare on Edwards Plateau and in 

 the Panhandle, and Okla. (Atoka, Kay and McCurtain cos.), Apr.-Oct.; from 

 Pa. and W. Va. to Mich., la. and Neb., s. to Fla. and Tex. 



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