18G 



COMPOSITE. (COMI'OSITE FAMILY.) 



Rays white or purple. No. 



Tappus none LEUCANTHEMUM. 66 



Pappus bristly EKIOEKON. 17 



Receptacle pitted. 

 Rays white or purple. 



Pappus double DIPLOP.\PPUS. 18 



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



Pappus single. Rays numerous. Pappus bristly ASTKU. 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 UETEROTIIECA. 23 



Pappus single. 



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



Leaves alternate. Heads racemed or clustered. . . . SOLI DAGO. 20 



Leaves alternate lleads paniclcd 1S0PAPPU3. 22 



Receptacle chalTy. 



Involucre double, the outer 4-leaved, 4-anglcd. . . . TETR.\.00N0TIIECA. 43 

 Involucre imbricated or spreading. 



Maritime shrubs. Pappus 4-toothed BORRICIIIA. 39 



Uerbs. 

 Receptacle conical or elongated. 



Rays persistent. Corolla-lobes velvety ZINNIA. 41 



Rays deciduous. Acheni:i 3 - 4-angled IIRLIOPSIS. 42 



R.ays deciduous. Achenia compressed SPIL.\NTIIES. 53 



Receptacle flat. 



Leaves lobed, alternate ACHILLEA. 65 



Leaves not lobed. Pappus 2-awncd. .... VEIIBESINA. 54 



Leaves not lobed. Pappus none. ECLIPTA. 38 



Wowers of the disk sterile. 



Rays yellow. Pappus none POLYMNIA. 30 



Rays yellow. Pappus a toothed crown CIIRYSOGONL'.M. 31 



Rays yellow. Pappus 2-toothed or awncd. Achenia winged. . . SILIMIIL'M. 32 



Rays yellow. Pappus 2-toothud or awned. Achenia wingless. . I5EUL.\NDir.llA. 33 



Rays white. Reccpt^icle conical I'AUTIIENIUM. 34 



Rays neutral (without pistils). 

 Receptacle caked, or nearly so. 



Achenia villous. Pappus scaly, long-awned. .... G.MLLARDIA. 56 



Achenia smooth or the angles hairy. Pappus awnless. . . . LE1'T0P0D.\. 00 

 Receptacle deeply pitted. 



Margins of tin; pits entire. Perennial BALDWINIA. 61 



Margins of the pits toothed. Annual ACTINOSPEllMUM. 62 



Recepta<-lc chalTy throughout. 

 Involucre double. Pappus 2 - 4-awned. 



Awns of the pappus hispid upward. C0I5E0P.SIS. 60 



Awns of the pappus hispid downward. Achenia boakless. . . UIUlONi'. o2 



Awns of the pappus hispid downward. Achenia beaked. . . • COSMOS. 61 

 Involucre simple or imbricate. 

 Pappus a cup-shnpcd border, or none. 



Chaff of the rcccpt.ncle ilongrited, spine-pointed. . . . ECHINACEA. 44 



Chad of the receptacle not elongated nor spine-pointed. . . RUDUECKIA. 45 

 Pappus 2 4-nwned. 



Achcnii wingc'l. I-onvos divided. Uoceptnclc elongated. . LEPACIIVS. 46 



Achonl.-i wiriped. Lenvi s luidiviiled. Hcceplnrlo convex. . ACTINOM EKIS. 49 



Achenia wInplcHH. Awns of the pappus dcriiluouH. . . HEM ANTIIIiS. 47 



Achenlii «lii({li''K. Awns of the piippus persisttint. . . HEL1ANI'IIEI.I,A. 4S 



Receptnclc chufT., uC (he apex. Achenia ribbed M.\1HJTA. 04 



