204 



COMPOSITE. (COMPOSITE FAMILY.) 



1. Heads discoid. 



* Heads with the flowers all perfect No. 



Pappus none. Leaves resinous-dotted, linear. Flowers yellow . . FLAVERIA. 69 

 Pappus none. Leaves opposite, ovate. Flowers yellow . . . VERBES1NA. 58 

 Pappus none. Leaves alternate. Flowers white .... HARTWRIGHTIA. 5 

 Pappus bristly or hairy. 

 Flowers yellow. 



Receptacle pointed BIGELOVIA. 21 



Receptacle flat SOLID AGO. 20 



Receptacle convex SENECIO. 80 



Flowers white, blue, or purple. 

 Receptacle chaffy. 



Leaves opposite. Flowers white MELANTHERA. 47 



Leaves alternate. Flowers purple CARPHEPHORUS. 7 



Receptacle bristly. 



Leaves spiny CNICUS. 84 



Leaves not spiny, cordate ARCTIUM. 85 



Receptacle naked. 



Scales of the involucre in a single row CACALIA. 83 



Scales of the involucre in 2 or more rows. 



Pappus double, the outer row very short VERNONIA. 1 



Pappus single. 

 Achenia ribbed or striate. 



Pappus plumose. Flowers cream-colored KUHNIA. 11 



Pappus scabrous. Leaves cordate. Flowers purple . BRICKELLIA. 12 

 Pappus scabrous. Leaves narrow. Heads racenied . . . LIATRIS. 8 

 Pappus scabrous. Leaves oblong. Heads panicled . . TRILISIA. 9 

 Pappus scabrous. Leaves obovate. Stems woody . . GARBERIA. 10 

 Achenia not ribbed, 5-angled. 



Receptacle conical CONOCLINItJM. 13 



Receptacle flat. Stems climbing MIKANIA. 14 



Receptacle flat. Stems erect EUPATORIUM. 13 



Pappus scaly. 

 Flowers blue or purple. 



Pappus a cup-shaped border of united scales AGERATUM. 4 



Pappus slender, almost bristly. 



Pappus deciduous. Heads large and single STOKESIA. 2 



Pappus persistent. Heads small, in 3-bracted clusters . ELEPHANTOPUS. 3 

 Pappus of 5 oval almost bony scales. Leaves whorled . . SCLEROLEPIS. 6 

 Flowers white. 



Receptacle naked. 



... ( POLYPTERIS. 67 



Leaves entire, linear or lanceolate [ AT^VTA 



( x AljAr UA.1A. uo 



Leaves entire, ovate or cordate AGERATUM. 4 



Leaves pinnately lobed HYMENOPAPPUS. GG 



Receptacle chaffy. 



Achenium top-shaped. Scales of the pappus 5 - 6 . . . MARSHALLIA. G5 



Acheiiium flat. Pappus 2-awned ACTINOMERIS. 59 



Flowers yellow. Pappus 2 - 4-awned. 



Awns of the pappus deciduous HELIANTHUS. 5G 



Awns of the pappus persistent, hispid upward . . . ... COREOPSIS. GO 



Awns of the pappus persistent, hispid downward BIDENS. 62 



* * Heads with flowers variously imperfect. 



Marginal flowers pistillate. Central flowers perfect, but abortive. 

 Pappus bristly. 

 Scales of the involucre in a single row ERECHTHITES. 82 



