410 Order 70.— COKPOSITA 



t Leaves altornsite. Pappus none. Achenia terete Anthemis. 69 



t Leaves alternate. Pappus none. Achenia obcompressed Achillea. 71 



t Leaves opposite. —Pap pus none ,...Ecupta. S8 



—Pappus of fringed scales Hds.sm. Eays 5, sm. white. §Ear. Galihsoqa. 



— Papp. of the disk a single awn of the ray 0. Zinnia. 48 



U Leaves opposite. Eays yellow. Pappus none Polthnia. S9 



u Leaves opposite. Eays yellow. Papp. a 2 or 3-toothed crown Chrtsogonum, 40 



u Leaves alternate. — Eays whitish, very short, 5 only Partiienium. 48 



— Eays yellow. — Achenia winged Silphium. 41 



— Achenia wingless Beelandiera. 42 



V Achenia with erectly hispid awns, or awnless ; never rostrate Coreopsis. 57 



V Achenia with retrorsely hispid awns, often attenuated above Biiibns. 58 



X Eays white, spreading. Pappus none Mardta. 70 



X Eays purple, pendant. Pales sharp, elongated Echinacea. 51 



X Eays yellow.— Pappus none. Achenia quadrangular. Eodbeceia. 52 



— Pappus none. Achenia compressed Lefaohis. 58 



— Pappus of2 deciduous awns. Ach. wingless Helianthus. 54 



— Pappus of 2 persistent teeth. Ach. winged Helianthella. 55 



—Papp. of2 persistent awns. Ach. broad-winged Aotinomeeis. 56 



B. Suborder, LIGULIPLOR^. 



§§ Pappus none, or consisting of little scales, (a) 



§§ Pappus double (of scales and bristles), or simple and plumous. (b) 



§§ Pappus composed of capillary bristles, not plumous. (*) 



* Achenia terete or angular, not'flattened. (c) 



* Achenia evidently flattened, (d) 



a Flowers yellow. Pappus none. Heads paniculate Lampsana. 98 



a Flowers yellow. Pappus none. Heads solitary or umbellate Apogon. 09 



a Flowers blue. — Pappus of many little scales. Eecept. naked , . . . . Cicuoeium. 100 



—Pappus of 5 scales. Eeceptacle chaflfy Catananche. 106 



b Flowers purple. Feathery pappus on a long filiform beak Tragopoqon. 104 



b Flowers white. Feathery pappus on a short beak or sessile Leontodon, 103 



b Flowers yellow. — Pappus of many bristles with the scales... Cynthia. 102 



— Pappus of 5 bristles and 5 scales Krigia. 101 



C Flowers whitish or purplish, mostly nodding. Stem leafy Nabalus. 107 



C Flowers rose-purple, erect. (Stem almost leafless.) Lygodesmia. Ill 



c Flowers yellow. — Achenia long-beaked. Pappus white Taraxacum. 109 



; — Achenia long-beaked. Pappus reddish Ptrropappus. 110 



— Achenia not beaked. — Pappus dull white or tawny Hieeacium. 105 



— Pappus bright white Teoximon. 108 



d Achenia contracted into a slender beak. Fls. mostly yellow Lactuoa. 112 



d Achenia scarcely beaked. — Flowers mostly blue Mulgeditim. 118 



—Flowers yellow. Papp. silky SonCuus. 114 



C. Suborder, LABIATIFLOR^. 



§§5 Head radiate, solitary, nodding in bud. Pappus capillary Chaptalia. 115 



Suborder I. TUBULIFLOR^. 



Tribk 1. VEENONIACE^. 



1. VERNO^NIA, Schreb. Iron Weed. (Named for William Vernon, 

 an English botanist who traveled in America in search of plants.) 

 Flowers all tubular, perfect ; involucre of ovate, imbricated scales, the 

 inner longest ; receptacle naked ; pappus double, the exterior chaffy, 

 the interior capillary. 2C Herbs or shrubs. Lvs. alternate. Fls. pur- 

 ple (in our species.) 



i Scoles of the involuoro an oMnso and closely npprossed No. 1 



a... ..^i-.j 1 / _.,_ flexuons pointa Nos. 2, 8 



I Bcojes 01 ine mvoiuore an ootuse and closely nppressed. . . 



: Scales of the Invol. (usually all)— with slender, nexuona pt 



— with acute or mucronatf 



— with acute or mucronate points Nos. 4,5,6 



