410 Order 70.— COMPOSITES. 



t Leaves alternate, ranpus Bono. Achenia terete. Ant-itemis. C9 



t Loaves alternate. Pappus none. Achenia obcomprcssed Achillea. 71 



t Leaves opposite. — Pappus none Eci.ihta. 88 



—Pappus of fringed scales Hds.sm. Rays5, sm. white. §Eur. Galinsoga. 



— Papp. of the disk a single awn of the ray Zinkla. 48 



U Leaves opposite. Rays yellow. Pappus none Polymni a. 89 



u Leaves opposite. Bays yellow. Papp. a 2 or 8-toothed crown Chktsogonum. 40 



U Leave3 alternate. — Rays whitish, very short, 5 only Parthenium. 43 



— Rays yellow. — Achenia winged Silpiih;m. 41 



—Achenia wingless Berlandikra. 42 



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



v Achenia with rctrorsely hispid awns, often attenuated above Burns. 58 



X Rays white, spreading. Pappus none Maruta. 70 



X Rays purple, pendant. Pales sharp, elongated Echinacea. 81 



X Rays yellow. — Fappus none. Achenia quadrangular Rcdceckia. 52 



— Pappus nono. Achenia compressed Lepachis. 03 



— Pappus of2 deciduous awns. Ach. wingless IIf.liantiilb. 64 



— Pappus of 2 persistant teeth. Ach. winged Heliantiikh,a. 65 



— Papp. of2 persistent awns. Ach. broad-winged AcriNO.MEr.is. 66 



B. Suborder, LIGULIFLOILE. 



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



§§ Pappus double (of scales and bristles), or simple and pi unions, (b) 



S§ 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. 99 



a Flowers blue.— Pappus of many little scales. Recept. naked , Cichorium 100 



—Pappus of 5 scales. Receptacle chaffy Catananciie. 106 



b Flowers purple. Foathcry pappus on a long filiform beak T ragopogon. 104 



b Flowers white. Feathery pappus on a short beak or sessile Leontodon. 108 



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. 307 



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



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



— Achenia long-beaked. Pappus reddish Pyrkopapptjs. 110 



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



—Pappus bright white Troximon. 108 



d Achenia contracted into a slender beak. Fls. mostly yellow Lactuoa. 113 



d Achenia scarcely beaked. — Flowers mostly blue Mui.gedium. 113 



—Flowers yellow. Papp. silky Son onus. 114 



C. Suborder, LABIATIFLOR/E. 



§S§ Head 'radiate, solitary, nodding in bud. Pappus capillary Cuaptalia, 116 



Suborder I. TTJBULIFLOR^E. 



Tribe 1. VERNONIACEvE. 



i. VERW(TNIA, 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 lougest ; receptaclo naked ; pappus double, the exterior chaffy, 

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

 ple (in our species.) 



§ Scides of the involucre all obtuse and closely appressed No. 1 



§ Scales of the invol. (usually all) — with slender, flexuous [mints .... . .'..'. !n'os. 2. 3 



— with ncut;: or mucronato points Nos. 4, 5, 



