574 POLYGONAOE^ ebiogonum 



oles : peduncles 1-4 feet high, rigid and rush-like : inflorescence a very dif- 

 fuse panicle : involucres glabrate, or glabrous, few, cylindrical or turbin- 

 ate-campanulate, repandly 5-toothed many-flowered, gathered in heads or 

 clusters, sometimes only ih pairs, or solitary in the forks : flowers white or 

 rose-color a little hairy at base the segments ovate-pblong, nearly equal. 

 On barren rocky places, eastern Washington to California. 



+- ■*- Leaves not fascicled : bracts small very rarely foliaceous below : 

 involucres mostly solitary in a repeatedly di- or trichotomous corymb- 

 like cyme. 



■•* Perennials, woody and diffusely much branched, leafy below. 



E. microthecum Nutt. Jour. Acad. Phila. ser. 2) i, 172. More or less 

 floccose-tomentose throughout: stems erect or ascending, branching, 

 especially from the base, 6-12 inches high : leaves oblong or oblanceolate, 

 obtuse at the apex, narrowed into short petioles, 6-12 lines long, the upper 

 bract-like: inflorescence compoundly cymose: involucres turbinate 1)4 

 lines long: flowers yellow, pink or white, campanulate, at length constrict- 

 ed near tie middle. Eastern Washington to California and Nebraska. 



E. corymbosum Benth. in DC. Prodr. xiv, 17. Densely floccose-to- 

 mentose throughout : stems erect, branched 6-12 inches high : leaves oblong, 

 obtuse at the apex, narrowed at base, petioled, 6-18 lines long, their margins 

 more or less crisp : inflorescence compoundly cymose : involucres short-cam - 

 panulate, 5-toothed, about IJ^ lines long, the teeth subacute flowers broadly 

 campanulate, 1-1 J^ lines long, constricted near the middle, the segments 

 fiddle-shaped, emarginate, the 3 inner ones shorter than the outer ones . 

 Eastern Washington to Nevada and Kansas. 



++ ** Perennial : less woody and more shortly branched at base : 

 leaves mostly narrow : sepals nearly equal. 



E. campannlatnm Nutt. 1. c. 163. Stems short, thick and woody 

 more or less tomentose: leaves crowded, narrowly oblanceolate, spatulate 

 or nearly linear, 1-3 inches long, obtuse at the apex, narrowed- inW Khg 

 petioles, whlte-tomentose on both sides, the margins sometimes revolute: 

 peduncles erector nearly so, glabrous, 4-12 inches high : inflorescences com- 

 poundly cymose: involucres oblong-turbinate, about a line long, with 5 

 obtuse teeth : flowers yellow, ovoid-campanulate, about a line long, the 

 segments oblong or fiddle-fihaped, emarginate. Eastern Oregon to Nebraska 



■^ •<- ■•- Involucres sessile and solitary along the ascending and 

 usually long-virgate branches of the open naked panicle: flowers 

 glabrous. 



■•+ White- tomentose perennials, leafy below: panicles sparingly 

 branched, usually virgate: involucres" tomentose, the teeth not 

 margined. 



E. strictum Benth. Branches very short: leaves small, ovate to oblan- 

 ceolate, on long slender petioles : peduncles very slender, glabrate above: 

 panicle twice or thrice divided, with 1-3 involucres on the short branches : 

 involucres glabrate, IJ^ lines long: flowers white to rose-color, IJ^ lines 

 long. In the Blue Mountains of Oregon. 



■^^ •"• Annuals : leaves usually rosulate at the base, sometimes 

 occuring at the nodes. 



E. virgatnm Benth. in DC. Prodr. xiv, 16. Usually whlte-tomentose 

 throughout : leaves oblong, an inch long, on slender |>etloles : peduncles 

 simple, or with a few erect virgate branches, 1-2 feet high : involucres re- 

 mote, 2 lines long, tomentose, the 5 teeth very short: flowers a line long 

 rose-color to white or yellow, glabrous, outer segflients broadly ovate, 

 cuneately narrowed at base, the inner about as long, spatulate-oblong. In 



