COMPOSITE. (COMPOSITE FAMILY.) 205 



Scales of the involucre in 2 or more rows. No. 



Pubescence woolly. Receptacle partly chaffy FILAGO. 33 



Pubescence woolly. Receptacle naked GNAPHALIUM. 32 



Pubescence tomeutose. Stem winged PTEROCAULON. 30 



Pubescence glandular. Heads corymbose PLUCHEA. 29 



Pappus a 5-lobed border. Flowers yellow TANACETUM. 77 



Pappus none. Leaves pinuately divided ARTEMISIA. 78 



Marginal flowers pistillate. Central flowers staminate. 



Pappus none. Style rigid, persistent ........ SOLIVA. 79 



Panpus none. Style deciduous. Heads nodding IVA. 41 



Marginal flowers neutral. Central flowers perfect . ... CENTAUREA. 86 



* * * Heads dioecious or monoecious. 



Stamiuate and pistillate heads on the same plant. 



Fruiting involucre 1-seeded, naked or tubercled AMBROSIA. 42 



Fruiting involucre 2-seeded, armed with hooked spines . . . XANTHIUM. 43 



Stumnate and pistillate heads on separate plants. 



Anthers tailed. Hoary herbs ANTENNARIA. 31 



Anthers tailless. Smooth shrubs BACCHARIS. 27 



2. Heads radiate. 

 Rays pistillate. 

 Flowers all fertile. 

 Receptacle naked. 

 Rays yellow. Leaves opposite. 



Pappus none. Heads 1-rayed FLAVERIA. 69 



Pappus scaly. Leaves fringed, dotted PECTIS. 73 



Pappus scaly. Leaves divided DYSODIA. 72 



Pappus capillary. Heads large ARNICA. 80 



Rays yellow. Leaves alternate. 



Scales of the involucre in 1 row SENECIO. 81 



Scales of the involucre in 2 rows HELENIUM. 71 



Scales of the involucre in several rows Heads large .... INULA. 28 



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



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

 Pappus single. 



Leaves alternate. Heads racemed or clustered . . SOLID AGO. 20 



Leaves alternate. Heads panicled .... APLOPAPPUS. 22 



Pappus of 2-8 bristles GRINDELIA. 25 



Rays white or purple. 



Pappus none. Rays pale purple BELLIS. 19 



Pappus none. Rays white CHRYSANTHEMUM. 76 



Pappus chaffy. Rays white .... ... BOLTONIA. 18 



Pappus bristly or capillary. 



Pappus double DIPLOPAPPUS. 16 



Pappus single. 



Rays few SERICOCARPUS. 15 



Rays numerous . . | ASTER. 16 



) ERIGERON. 17 

 Receptacle chaffy. 



Involucre double, the outer 4-leaved, 4-angled . . . TETRAGONOTHECA. 50 

 Involucre imbricated or spreading. 



Maritime shrubs. Pappus 4-toothed BORRICHIA. 45 



Herbs. 

 Receptacle conical or elongated. 



Rays persistent. Corolla lobe", velvety ZINNIA. 48 



Rays deciduous. A- li'-ni i .')-4-aiigl'l . . . HELIOPSIS. 49 



Rays deciduous. Aclienia, compressed . , . SPILANTHES. 51 



