POLESIOMACEiE. 81 



€Umple or sparingly branched: flowers seBsile in dense leafy-bnicted heada: corolla Balver- 

 form 



CoroUa-tabe little or not at all exserted beyond the leafy bracts. 11, 15, 16 



Corolla tube much exserted 12, 13, 14 



• • Leaves alUmate, lobed or parted; rarely a few entire or opposite. 



♦ Leaves palmately parted into rigid pungent divisions: stems looody: jlowers large^ sessile: 



corolla salverform: stamens included 17, 18 



+ t Leaves pedateiy 5 -7 -parted: soft' kairy perennials. 



Flowers white in dense heads: some leaves 3-parted or entire 34 



Flowers violet or purplish, solitary, subsessile in forks or axils 35 



t ft Leaves pinnately incised cleft or divided^ rarely a few entire or opposite: bracts some- 

 times nearly palmately cleft. 

 a. Flowers in dense leafy-hraeted clusters or heads: lobes of the calyx^ brads and upper 



leaves mostly rigid and pungent. 

 Much branched annuals: sometimes viscid: never woolly except in th&heads^stigmaaoften 

 only 2, 

 At least some of the leaves bipinnatifid. 



More or less viscid; odor disagreeable 19, 20 



Not viscid: leaf-segments filiform 21 to 24 



Leaves simply pinnatifid or many entire. 



Not viscid; bracts and calyx fine-woolly 25 



Viscid 28 to 28 



Densely woolly, at least when young: corolla salverform: stamens exserted. 



Leaves rigid, not viscid: filaments exserted; anthers sagittate 29 to 33 



Leaves not rigid: petioles broad: flowers small, white, numerous 34 



6. Inflorescence brajctless or nearly so: leaves not rigid or pungent. 



Stems from creeping rootstocks, 1 or 2 incher high 35 



Flowers in long-peduncnlate ovoid heads: leaf -lobes filiform 36. 37 



Flowers clustered or solitary: leaf -lobes slender (except 41) 38 to ^4 



Corolla pinkish, slender, twice as long as caljTt 45, 46 



• * * Leaves entire {rarely 2 or S small lobes), aUemate, or the lower opposite, sessile: corolla 



salverjorm to funnelform: stamen unequally inserted: more or less viscid annuals. 



Flowers on filiform peduncles: corolla pink, 5 to 10 lines long. 47 



Flowers in loose cluster or scattered: calyx -lobes slender 48 



Flowers in the forks and upper axils: calyx-lobes awn-like 49 



Flowers in leafy-bracted capitate clusters or a few scattered. 



Calyx-lobes acute : corolla 5 lines long 50 



Cjklyx-lobes obtuse: corolla 10 to 15 lines long 61 



§ 1. Dactylophylluin, Gray. 



I. O. liniflora, Benth. Corolla white or jniikish, nearly rotate. W. CaL 



11 



