174 TENTANDRIA. DIGYSriA. 



251. EVOLVLLUS. L, 



Calix S-parted. Corolla rotate-campannlate'^ 

 lobes subemai'ginate. Styles 2, deeply bifid; 

 segments capillary and divergent. Stigma sim- 

 ple. Capsule S-celled, 4-valved, 2 to 4 seeded. 



Stem creeping-, procumbent, or erect. Leaves alter- 

 nate entire; flowers pedunculate, small; peduncles soli- 

 tary," bibracteate, capsule perfecting 1, 2, or 4 seeds. 



Species. 1. JC. mnmmdanus. On the banks of the 

 Mississippi, near New Orleans. 2. sericeusP Stem diffuse 

 and procumbent? Leaves remote, sessile, oblong-lanceo- 

 I^te, sublinear, acute at both extremities, under side, 

 .somewhat silky villous; pedimcle 1-flowered, shorter than 

 the leaf, bibracteate, bracies seated in the axill. Obs. 

 Stem almost filiform, somewhat villous; leaves 5 to 10 

 lines long, 1 to 2 lines broad, peduncles 2 to 3 lines long-; 

 flower white, convolvulaceous, plaited, external mar^^in of 

 the plaits villous; segments of the calix ovale, acuminate; 

 capsule 2.celled, 4-valved, 2-seeded. Hab. Around St. 

 Mary's, in Florida, Dr. Baldwyn v. s. 



3. argenteiis, P«. (pilosvs.) Perennial; stems simple, 

 erect, and low, many from the same root: the whole plant 

 densely hairy and sliining: leaves cuneate-oblong-, acute, 

 crowded; peduncles 1-fiowered, subsessiie; bibracteate, 

 bractes sessik in the axill; segments of the calix linear. — 

 Obs. Allied to E. Commersoni. Stems 4 to 6 inches hieh; 

 leaves 6 to 8 lines long, 2 to 4 wide, extremely hairy as 

 well as the stem; flowers solitary, appearing sessile, pur- 

 ple, edge of the plaits hairy, capsule 4-valved, often per- 

 fecting only a single seed. — Hab. Op and gravelly hills 

 near the confluence of Rapid river and the Missouri;flow- 

 ering in May. This genus, with the above exceptions, 

 exists exclusively within tiie tropical regions of India^ 

 Australia, and America. 



if Flowers pentapetalous, inferior, 



252, HEUGHERA. L. (Allum-root.) 



Calix 5-clert. Petals 5, small. Coj^sw^e bi ros- 

 trate, bilocular, many-seeded. 



Leaves radical; flowers small, in a thyrsoid panicle. 



Species. 1. H. ajnericana. 2. villosa. On the moua- 

 tains of North Carolina, Virginia, and Tennessee. S: 

 caideccens, Ph. 



