574 POLYGONACEZ ERIOGONUM 
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 in pairs, or solitary in the forks: flowers white or 
rose-color a little hairy at base the segments ovate-oblong, 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 144 
lines long: flowers yellow, pink or white, campanulate, at length constrict- 
ed near the 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 114 lines long, the teeth subacute flowers broadly 
campanulate, 1-114 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. campanulatum 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 into long 
petioles, white-tomentose on both sides, the margins sometimes revolute: 
peduncles erect or 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-shaped, 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: 
anicle twice or thrice divided, with 1-3 involucres on the short branches: 
involucres glabrate, 144 lines long: flowers white to rose-color, 134 lines 
long. In the Blue Mountains of Giegbt: 
++ ++ Annuals: leaves usually rosulate at the base, sometimes 
occuring at the nodes. 
E. yvirgatum Benth. in DC. Prodr. xiv, 16. Usually white-tomentose 
throughout: leaves oblong, an inch long, on slender petioles: peduncles 
simple, or with a few erect virgate branches, 1-2 feet high: involucres re- 
mote, 2lines long, tomentose, the 5 teeth very short: flowers a line long 
rose-color to white or yellow, glabrous, outer segments broadly ovate, 
cuneately narrowed at base, the inner about as long, spatulate-oblong. in 
