4. Faces of the stem flat to convex and essentially equal; stem with conspicuous 



wings (to about 2 mm. wide) and spongy-thickened below or (if 

 neither) then with hairs on the abaxial surface of the petals and 

 on the mature hypanthium; leaves sessile or nearly so; flowers rose 

 to purple (5) 



5(4). Roots tuberous; stem with conspicuous wings and often spongy-thickened 

 below; leaves frequently broadest near the base; hypanthial neck 

 rarely longer than the body of hypanthium 4. R. virginica. 



5. Rootstock rhizomatous, nontuberous; stem lacking conspicuous wings and 



rarely spongy-thickened below; leaves frequently broadest near the 

 middle; hypanthial neck usually longer than body of hypanthium 

 3. R. mariana var. interior. 



1. Rhexia petiolata Walt. Fig. 547. 



Plant to 6 dm. tall; leaves to 25 mm. long and 15 mm. wide, 3-nerved, somewhat 

 petiolate; hypanthium glabrous at maturity, 5-9 mm. long; calyx lobes to 4 mm. 

 long and 3 mm. wide, with serrate to ciliate margins; petals rose-color, elliptic, to 

 2 cm. long. R. ciliosa Michx. 



In peaty or sandy soils of wet pinelands and evergreen shrub or pitcher plant 

 bogs, in s.e. Tex., July-Sept.; along coast from s.e. Va. to cen. Fla., w. to Tex. 



The typically oval leaves and sessile flowers are characteristics of this species. 



2. Rhexia lutea Walt. Fig. 548. 



Plant to 5 dm. tall, the stems usually much-branched; leaves to 25 mm. long and 

 8 mm. wide, 3-nerved, essentially sessile; hypanthium at maturity glabrous or with 

 few scattered glandular hairs, 5-8 mm. long; calyx lobes to 3 mm. long and wide, 

 with glandular hairs on margins; petals yellow, elliptic, to 13 mm. long. 



In wet savannahs and open pinelands, hillside seepage and bogs of s.e. Tex., 

 May-June; along coast from e. N.C. to n. Fla., w. to Tex. 



The yellow petals are distinctive. 



3. Rhexia mariana L. var. mariana. Fig. 549. 



Plant to 7 dm. tall, the stem with axillary branches; leaves petiolate, elliptic to 

 lanceolate, to 6 cm. long, the margins serrate, ciliate; calyx lobes triangular to 

 lanceolate, to 3 mm. long; petals obovate, to about 18 mm. long. Incl. var. exalbida 

 Michx. 



In marshes, ditches, wet meadows, seepage bogs, savannahs, edge of thickets and 

 similar places that are wet or moist, throughout e. Tex. and e. Okla. (McCurtain, 

 Haskell, LeFlore and Pushmataha cos.), May-Sept.; from Mass. s. to Ga., w. to 

 Tex. and Okla., n.w. to Mo., 111. and Ind. 



The leaves narrowed to petioles readily distinguish this species from R. virginica. 



Var. interior (Penn.) Krai & Bostick. 



This is not an altogether clear taxon, especially since it has some characteristics 

 usually attributed to R. virginica. It may well represent a hybrid but for the present 

 we follow the most recent revisionists of this genus. R. interior Penn. 



In water of ponds, marshes and lowlands; centered in the interior prairies of Mo. 

 and Kan., extending e. to Ind., Ky. and Tenn. and s. to La., Tex. and e. Okla. 

 (LeFlore, Adair, Sequoyah and McCurtain cos.). 



4. Rhexia virginica L. Common meadow beauty. Fig. 550. 



Plant to 1 m. tall; leaves ovate to ovate-lanceolate or elliptic, to 1 dm. long and 

 35 mm. wide, the margins serrate-ciliate, sessile or with petioles to 5 mm. long; 

 hypanthium to 1 cm. long, glandular-hispid at maturity; calyx lobes triangular to 

 lanceolate, to 2.5 mm. long; petals dark-rose-color to purple, obovate, to 17 mm. 

 long. 



1172 



