COMPOSITAE (COMPOSITE FAMILY) 779 



Receptacle flat or nearly so. 



Achenes cylindrical, 2-awned 55. Thele»perma. 



Achenes flattened parallel to the chaff. 



Pappus-awna barbed 56. Bidens. 



Pappus-awns not barbed 54. Coreopsis, 



Keceptacle convex to columnar. 

 Involucral bracts with thin scarious margins . . . . 6S. Anthemis. 

 Involucral bracts distinctly herbaceous. 

 Pappus of 2 awns. 



Pappus-awns very deciduous 51. Heliantfius. 



Pappus-awns persistent 52. Actinomeris. 



Pappus none or a crown of short teeth. 



Eays rose-color (rarely yellow), pistillate . , . . 47. Brauneria. 



Eays yellow to brownish-red or orange, neutral. 



Achenes 4-sided, marginless 46. Eudheckia. 



Achenes flattened and margined 4S. Lepachys. 



q. Rays pistillate and fertile i\ 



r. Disk-flowers also fertile, their achenes maturing s. 

 «. Leaves alternate. 



Pappus of 1-3 awns or teeth 53. Verbesina. 



Pappus none. 

 Heads less than 1 cm. broad ; achenes obcompressed . • 67. Achillea. 

 Heads more than 1 cm. broad ; achenes not compressed . 6S. Aiitltemis. 

 8. Leaves opposite. 



Maritime shrub 50. Botrichia. 



Herbs. 



Annual, with white rays 44. Eclipta. 



Perennial, with yellow ra\'s. 



Outer involucre of 4 connate bracts 45. Tetragonotheca. 



Outer involucral bracts not connate. 



Weak creeping herb 49. Spilanthes. 



Stout erect herbs. 



Achenes laterally flattened 53. Verbesina. 



Achenes thickish 43. Heliopsis. 



r. Disk-flowers not maturing achenes ; disk chafiy. 

 Achenes thickish, not strongly flattened. 



Inner bracts of the involucre not armed 38. Polymnia. 



Inner bracts of the involucre glochidiate, closely investing the 



achenes Si. Acarit/iospermuri'. 



Achenes flattened dorsally. i.e. parallel with the chaff. 

 Eays 5, obcordate, scarceh* exceeding the disk, whitish . . 3S. PariheJiium . 

 Kays yellow, much longer than the disk. 

 Achenes wing-margined, in several rows .... 35. Silphiuin. 

 Achene wingless, in a single row. 



Eays 5 ; leaves serrate 37. Chrysogonum. 



Kays usually more numerous ; leaves dentate or lyrately 



lobed 36. Berlandiera. 



Series II. All the flowers of the head with strap-shaped corolla t 



t. Pappus none. 



Leaves basal 90. Arnoseris. 



Leafy-stemmed. 



Involucre calyculate 88. Lapsana. 



Involucre not calyculate 89. Serinia. 



t. Pajjpus wholly or in "part of scales. 



Flowers blue, rose-colored, or rarely white 91. OicJioi-ium. 



Flowers yellow 92. Krigia. 



t. Papjtus bristle-formed, capillary u. 

 u. Bristles plumose. 

 Leaves basal. 

 Inner achenes long-beaked ........ 93. Hypochaeris. 



Inner achenes not beaked 94. Ltoniodon. 



Leafy-stemmed. 



Hispid -pubescent , .... 95. Picids. 



Glabrous 96. Tragopogon. 



V/. Bristles simple, at most scabrous id. 



V. Achenes strongly muricate or epinulose above. 



Leafv'-stemmed . ' 97. Chondrilla. 



Scapose 98. Taraxacum. 



T, Achenes not muricate above to. 

 w. Achenes flat or flatfish. 



Achenes beakless : flowers 50 or more in each head, yellow . 99. Sonchiut. 

 Achenes mostly beaked ; heads 6-30-flowered ; flow"ers yellow, 



blue, or purple 100. Lactuca. 



W. Achenes columnar, often slender. 



Flowers cream-color, white, rose-color, or purple. 



Pappus white ; heads erect 101. Lygodesmia 



Pappus cream-color or tawny ; heads nodding . . . . 105. Prenanthe^. 



