480 COMPOSITAE (COMPOSITE FAMILY) 



Tribe IX. CYNAREAE 

 Leaves and usually the involucral bracts prickly .... 91. Carduus. 



Tribe X. CICHORIEAE 



Pappus plumose or scale-like. 

 Flowers not yellow. 

 Achenes beakless. 



Pappus of bristle-form scales 92. Cichorium. 



Pappus plumose 93. Stephanomeria. 



Achenes beaked . .94. Tragopogon. 



Flowers yellow. 



Involucral bracts in 1 row ....... 95. Krigia. 



Involucral bracts in 2 or more rows. 



Pappus scales unequal; achenes fusiform .... 96. Nothocalais. 



Pappus scales tipped with a plumose bristle; achenes linear 97*. Ptilocalais. 

 Pappus of capillary bristles, never plumose. 



Pappus deciduous, all the bristles falling away together, except 



1-8 stouter ones which may persist 98. Malacothrix. 



Pappus persistent or the bristles falling separately. 

 Flowers rose or purplish. 



Annuals 100. Prenanthella. 



Perennials. 



Stems nearly leafless ....... 99. Lygodesmia. 



Stems with ample leaves 101. Prenanthes. 



Flowers yellow, blue, or white. 



Stems more or less leafy; heads several to many (rarely soli- 

 tary). 

 Achenes not flattened. 



Pappus white ........ 102. Crepis. 



Pappus sordid or fulvous 103. Hieracium. 



Achenes flattened. 



Involucre cylindraceous ...... 104. Lactuca. 



Involucre campanulate 105. Sonchus. 



Stems scapose, with solitary heads. 



Achenes not spinulose at apex . > . . . . 106. Troximon. 

 Achenes spinulose at apex 107. Taraxacum. 



Synoptical Key to the Genera 



Series A. TUBULIFLORAE 



Corolla tubular in all the perfect flowers, regularly 5 (rarely 3-4) -lobed, 

 ligulate only in the marginal or ray-flowers, which when present are either 

 pistillate only, or neutral (with neither stamens nor pistil). 



Tribe I. VERNONIEAE. Heads discoid; the flowers all alike, perfect and tubular, never 

 yellow. Branches of the style long and slender, terete, thread-shaped, minutely 

 bristly-hairy all over. Leaves alternate or scattered. 



1. Vernonia. Heads several-many-flowered, separate. Involucre of many bracts. 



Pappus double, the inner capillary, the outer of minute chaffy bristles. 



Tribe H. EUPATORIEAE. Heads discoid; the flowers all alike, perfect and tubular, never 

 yellow. Branches of the style thickened upward or club-shaped, obtuse, very minutely 

 and uniformly pubescent; the stigmatic lines indistinct. 

 * Pappus of slender bristles. 

 - Achene 5-angled; bristles of^the pappus roughish. 



2. Eupatorium. Involucre of more than 4 bracts and the flowers few or many. 



H--J- Achene 10-ribbed; involucral bracts striate-nerved. 



3. Kuhnia. Pappus very strongly plumose. Bracts of the involucre few. 



4. Brickellia. Pappus merely scabrous. Involucral bracts in several series. 



5. Liatris. Pappus plumose or only barbellate. Corolla red-purple, strongly 5-lobed. 



Heads spicate or racemose, the involucre well imbricated. 



Tribe in. ASTEREAE. Heads discoid, the flowers all alike and tubular; or else radiate, the 

 outer ones ligulate and pistillate. Anthers not caudate at base. Branches of the style 

 in the perfect flowers flat, smooth up to where the conspicuous, marginal, stigmatic lines 

 abruptly terminate, and prolonged above this into a flattened lance-shaped or tri- 

 angular appendage which is evenly hairy all around or pubescent outside. Leaves 

 alternate. Receptacle naked (destitute of chaff) in all our species. 



* Ray-flowers yellow, or sometimes none at all. 



+- Pappus of not numerous slender bristles; heads radiate; involucre of firm bracts with 

 greenish tips, commonly coated with resin. 



6. Gutierrezia. Heads small, numerous; ray- and disk-flowers 1-10 each, all fertile. 



Pappus of several short chaffy scales. Suffrutescent; leaves very narrow. 



7. Grindelia. Heads large, many-flowered; flowers all fertile. Pappus of 2-8 rigid 



caducous awns. Coarse herbs with toothed leaves. 

 - H- Pappus (at least of the disk) of copious slender or capillary bristles. 



