PIPER FLORA OF THE STATE OF WASHINGTON. 555 



Receptacle not conical. 



Heads slender-peduncled ; pistillate flowers apetalous Cotula (p. 586). 



Heads clustered; corollas present. 



Pappus a short crown; heads corymbed Tanacetum (p. 586). 



Pappus none; heads racemose or panicled Artemisia (p. 586). 



SENECIONEAE. 



Shrub; involucre of 4 to 6 concave bracts Tetradymia (p. 590). 



Herbs. 



Jjeaves all or mostly opposite Arnica ( p. 590) 



Leaves alternate. 



Flowers whitish or pinkish ; lieads rayless. 



Leaves large, palmately lobed, mostly basal. 



Styles united nearly to the apex Petasites (p 593). 



Styles united about half way Cacaliopsis ( p. 594). 



Leaves entire ; stems leafy. 



Heads about 10-flowered, corymbed Luina (p. 594). 



Heads 4 to 6-flowered, paniculate Rainiera (p. 594). 



Flowers yellow; rays present (except in a few species of 

 Senecio). 



Involucre hemispheric; heads solitary Crocidium (p. 594). 



Involucre campanulate; heads usually corymbose Senecio (p. 595). 



INULEAE. 



Pappus capillary, at least in pistillate flowers. ' 



Plants dioecious or polygamo-dioecious. 



Pappus of staminate flowers clavate Antennaria (p. 601 ). 



Pappus of all the flowers similar Anaphalis (p. 606). 



Plants not dioecious; flowers all fertile Gnaphalium (p. 606). 



Pappus none. 



Receptacle naked; leaves large, green above Adenocaulon (p. 607). 



Receptacle chaffy ; leaves small, woolly Psilocarphus ( p. 607 ). 



CYNAREAE. 



Akenes obliquely attached by one side at base. 



Heads not subtended by bristly leaves Centaurea (p. 608). 



Heads sessile, subtended by bristly leaves Cnicus (p. 608). 



Akenes attached by the very base, not oblique. 



Filaments monadelphous below Silybum (p. 609). 



Filaments distinct. 



Leaves and usually the involucral bracts prickly Carduus (p. 609). 



Leaves not prickly. 



■ ' Heads globose, the bracts hook-tipped Arctium (p. 611 ). 



Heads oblong, tEe bracts unarmed Saussurea (p. 611 ). 



ETJPATORIUM. 



1. Eupatoriunx occidentale Hook. Fl. Bor. Am. 1: 305. 1833. 



Krystenia occidentalis Greene, Leaflets 1 : 9. 1903. 



Type locality: "On the low hills between the north and south branch of Lewis and 

 Clarks River in stony places." Collected by Douglas. 



Range: Washington and Idaho to California. 



Specimens examined: West Klickitat County, Suksdorf 865; Ellensburg, Elmer 423 

 1084; Klickitat River, Suksdorf, July 16, 1886. 



