PIPER—FLORA OF THE STATE OF WASHINGTON, 233 
ERIOGONUM. 
Flowers not stipe-like at base. 
Involucre nerveless; branches leafy; annual....-....... 1. EF. angulosum. 
Involucre distinctly nerved. 
Outer perianth segments much broader than the inner. 
Umbel simple, close; plants densely cespitose. 
Involucre campanulate; flowers 3 to 4 mm. 
long, white or yellow... ......-.-.------- 2. KE. ovalifolium. 
Involucre turbinate; flowers 4.5 to 5.5 mm. 
long, wine red __........--..-.-.------ 3. E. vineum. 
Umbel compound; plants loosely cespitose. 
Involucres in clusters; flowers white, yellow, 
or purple... 22.2.2 .2---- 2-2 --2---2-2--- 4. BE. proliferum. 
Involucres scattered, mostly solitary; flowers 
white. 
Plants erect or ascending ...........-. 5. FE. niveum. 
Plant decumbent......-.-..--------- 6. FB. decumbens. 
Outer perianth segments like the inner. 
Shrub, much branched; leaves linear to oblanceo- 
late... 2-2-2 eee eee eee eee ee 7. E. microthecum. 
Herbs. 
Annuals; stems wiry; leaves rosulate. 
Involucre 3 mm. long. .......-..-.-.- 11. EF. vimineum. 
Involucre 1 to 1.5 mm. long... --.--.- - 12. FE. baileyi. 
Perennials. 
Plants very dwarf and very leafy; pe- 
duncles bearing a single involucre.... 13. HB. minimum. 
Plants tall, not very leafy; peduncles 
bearing more than one involucre. 
Peduncles stout, fistulous; involu- 
cres 3 to 6 in each cluster. 
Leaves ovate-oblong, acute, 5 
to 15 em. long. _.....-..-- 8. EF. elatum. 
Leaves oblong or ovate, obtuse, 
1 to 5em. long. ..-..------ 9. EB. nudum. 
Peduncles slender, not fistulous; in- 
volucres scattered in a_ loose 
cyme...-.-.-.-2-.---2-------- 10. FE. strictum. 
Flowers attenuate and stipe-like at base. 
Perianth pubescent. 
Involucre with refiexed lobes. 
Prostrate or nearly so, only the flowering stems 
upright; flowers cream color; leaves oblong 
or spatulate, not revolute... -...-.---.-.---- 14. FE. douglasii. 
Erect, much branched; flowers bright vellow; 
ies) 
leaves linear or linear-spatulate, often revolute. 15. FE. sphaerocephalum. 
Involucre with erect lobes or teeth. 
Shrubby; leaves linear, revolute... ......-.-.- 16. E. thymoides. 
Herbaceous; leaves oblong or obovate, not 
revolute. 
Flowers yellow; bracts 3 to8 .........---- 17. E. piperr. 
Flowers purplish; bracts 2.........-..---- 18. FE. pyrolaefolium. 
Perianth glabrous. 
