18G 



COMPOSITE. (COMPOSITE FAMILY.) 



Rays white or purple. No. 



Pappus none. . LEUCANTIIEMUM 66 



Pappus bristly ERIGERON. 17 



Receptacle pitted. 

 Rays white or purple. 



Pappus double. DIPLOPAPPUS. 18 



Pappus single. Rays about 5. Achenia silky. . . SER1COCAKPUS 15 



Pappus single. Rays numerous. Pappus bristly ASTER. 16 



Pappus single. Rays numerous. Pappus scaly. . . . BOLTONIA. 19 

 Rays yellow. 



Pappus double, of the ray and disk flowers alike. . . . CIIRYSOPSIS. 24 



Pappus double, of the ray flowers none. .... HETEIIOTIIECA. 23 

 Pappus single. 



Leaves opposite. Heads large, single or corymbose. . . . ARNICA. 76 



Leaves alternate. Heads racemed or clustered. . . . SOLIDAGO. 20 



Leaves alternate Heads panicled ISOPAPPUS. 22 



Receptacle chaffy. 



Involucre double, the outer 4-leaved, 4-angled. . . . TETRAGONOTHECA. 43 

 Involucre imbricated or spreading. 



Maritime shrubs. Pappus 4-toothed BORRICIIIA. 39 



Herbs. 

 Receptacle conical or elongated. 



Rays persistent. Corolla-lobes velvety. ZINNIA. 41 



Rays deciduous. Achenia 3 - 4-angled HELIOPSIS. 42 



Rays deciduous. Achenia compressed SPILANTHES. 53 



Receptacle flat. 



Leaves lobed, alternate ACHILLEA. 65 



Leaves not lobed. Pappus 2-awned. .... VEltBESINA. 54 



Leaves not lobed. Pappus none. ECLIPTA. 38 



Flowers of the disk sterile. 



Rays yellow. Pappus none POLYMNIA. 30 



Rays yellow. Pappus a toothed crown . CIIRYSOGONUM. 31 



Rays yellow. Pappus 2-toothed or awned. Achenia winged. . . SILPIIIUM. 32 



Rays yellow. Pappus 2-toothed or awned. Achenia wingless. . BERLANDIERA. 33 



Rays white. Receptacle conical PARTIIENIUM. 34 



Rays neutral (without pistils). 

 Receptacle naked, or nearly so. 



Achenia villous. Pappus scaly, long-awncd. .... GATLLARDIA. 56 



Achenia smooth or the angles hairy. Pappus awnless. . . . LEPTOPODA. 60 

 Receptacle deeply pitted. 



Margins of the pits entire. Perennial BALDWTNIA. 61 



Margins of the pits toothed. Annual ACTINOSPERMUM. 62 



Receptacle chaffy throughout. 



Involucre double. Pappus 2 - 4-awned. 



Awns of the pappus hispid upward. COREOPSIS. 50 



Awns of the pappus hispid downward. Achenia bcakless. . . BIDENS. 52 



Awns of the pappus hispid downward. Achenia beaked. . . . COSMOS. 51 

 Involucre simple or imbricate. 

 Pappus a cup-shaped border, or nnne. 



Chaff of tbe receptacle elongated, spine-pointed. . . . ECHINACEA. 44 



Chaff of Hie receptacle not elongated nor spine-pointed. . . RUDBECKIA^ 45 

 Pappus 2 4-awned. 



Achenia winged. Leaves' divided. Receptacle elongated. . . LEPACIIYS. 46 



Achenia winged. Leaves undivided. Receptacle convex. • APTINOMERIS. 49 



Achenia wingless. Awns of tlic pappus deciduous. . . IIELI ANTIIUS. 47 



Achenta wingless. Awns of the pappus persistent • ■ HELIANTHELLA. 48 



Receptacle chaffy at the apex. Achenia ribbed • MARUTA. 64 



