280 ORDER 1(H. POLYCJONACEJE. 



ent. Sta. 1 4. Fruit 5-ribbed, truncate at apex, 1-seeded. @ Leaves 



petiolate. Flowers very small. 



B. erecta L. Glabrous ; Ivs. ovate, wavy, pale beneath ; clusters 3-G-fl\vd., distant in 



a strict panicle with filiform branchlets. Sands, S. 2 4f. June Sept. 

 B. liirsiita, and B* viscosa, grow in S. Fla., according to Dr. Chapman. 



ORDER CIV. POLYGONACE^E. SORRELWORTS. 



Herbs (rarely shrubs) with alternate leaves and mostly sheathing stipules 

 (pchrece) surrounding the stem above each tumid joint. Flowers mostty 

 perfect. Perianth (or calyx) 3-6-cleft, mostly colored, imbricated in bud 

 and persistent. Stamens 4 15. Ovary 1-celled, free, with a single, erect 

 ovule. Styl-es or stigmas 2 or 3. Fruit a 3-angled achenium enclosed in 

 the calyx. Seed erect, albuminous, with a curved embryo. Figs. 147, 

 151-4, 286, 304, 313, 337, 521. 



Ochreae, or sheathing stipules, present at each joint... (6) 



Ochreie none. a Flowers in involucrate umbels, 6-sepalled ERIOGONUM. 1 



a Flowers in bracted racemes, 5-sepalled. Stems with tendrils BBUNNICHIA. 2 



b Sepals 4, equal by pairs. Stamens 6. White Mountains: rare OXYRIA. 3 



b Sepals 6, all similar. Stamens 9. In gardens: common RHEUM. 4 



b Sepals 6, the 3 inner increasing, tuberculate KU.MKX. 5 



/> Sepals 5 (in one Polygonum 4 irregular). ,.fe) 



c Sepals all or the 3 inner fvinged. Pedicels solitary THYSANELLA. 6 



c Sepals all entire, x opc, or 3 closed on the fruit. Pedicels solitary... . ....POLYGONELLA. 7 



a; open at base of fruit. Pedicels fascicled FAGOPYRUM. 8 



x closed on the angular fruit. Herbs POLYGOXUM. 9 



x combined with the round fruit. Trees. Fla COCCOLOBUS. 



1. ERIOGONUM, MX. Fls. many in each common 5-toothed involu- 

 cre. Cal. deeply 5-cleft. Sta. 9, sty. 3. Ach. 3-angled or 3-lobed. Herbs 

 clothed with down or wool. Lvs. alternate, exstipulate, mostly at the base 

 of the stem, the upper bract-like, often whorled at the forks of the umbel- 

 late inflorescence. Very abundant in the Pacific States. June Aug. 



1 E. tomentosum MX. Lower Irs. crowded, oblong-obovate, rusty-white beneath, 



the upper whorled in 3's ; involucre sessile ; calyx colored, li Dry soils, S. 2 3f. 



2 E. longilolium N. Lower Ivs. crowded, oblong-linear, white beneath, the upper 



scattered ; involucre pedunculate ; calyx green, woolly. Fla., and W. 2 4f. 



2. BRUNNICHIA, Banks. Calyx colored, 5-partcd, lobes oblong, at 

 length increased and closed on the obscurely 3-angled achenium. Fil. 8, 

 capillary, styles 3, slender, stigmas entire. ~j> Tetv.lrils from the ends of 

 the branches. Flowers racemed, greenish. 



B. cirrliosa Banks. A smooth, shrubby vine, 10 20f, on river b:.uk?, Car. to Fla., 

 and W. Leaves cordate to ovate, entire. Sheaths obsolete. May. 



3. OXYRIA, Ix. Br. MOUNTAIN SORREL. Cal. herbaceous, 4-sepalled, 

 the 2 inner sepals erect, larger, the 2 outer reflexed. Ach. lens-shaped, 

 thin, girt with a broad, membranous wing. Sta. G, equal. Stig. 2, sessile, 

 penicillate. 2 Low, nearly acaulescent, alpine plants. 



O. reull'ormis Hook (or digyr.a Camp.) Root leaves on long stalks 3 , reniform ; outer 

 epal* } ft* long a* the loner ; fruit orbicular. White Mountain?, and N. ;;!'. June. 



