OKDER LXIV. COMPOSITE COMPOSITE-FAMILY. 



165 



cylindrical, with the linear, green scaled in a single row. Pappus abundant, 

 white, very soft. 



GROUP 4. 

 Central flowers perfect; marginal mostly enlarged and sterile. 



40. CENTAUKU. Receptacle bristly. Pappus composed of capillary, rough 

 bristles, In several rows. 



41. AXBERBOA. Pappus consisting of oblong, or obovate, chaffy scales; 

 rarely small or none. 



OEOUP 5. 



Heads consisting wholly of either stamlnate or pistillate flowers (rarely in 

 Antennaria a few stamlnate flowers In the centre of the pistillate beads). 



84. ANTENNAE:*. Plants with dioecious flowers. Receptacle somewhat 

 convex, alveolate. Woolly herbs. 



36. XANTHIUM. Plants with monoscious flowers. Starninate in short, ler- 

 mlnal racemes ; pistillate ones in small clusters, at the base of the staminate. 

 Fertile heads 2-nowered, covered with hooked prickles, forming a burr. Pappus 

 n-Mi-. 



87. AMBROSIA. Flowers monoecious. Sterile flowers nodding. In long ra- 

 cemes. Fertile flowers In a closed, 1-flowered involucre, axillary, near the 

 base of the sterile raceme. 



b. Louxr leavet at leattopporitt or verticittate. 



GROUP. 6. 



Central and marginal flowers perfect 



2. KcpATdalUM. Heads 3 many-flowered. Involucre-scales S or more. 

 Pappus simple, capillary. Receptacle naked. Erect herbs. 



8. MIKAMA. Heads 4-tlowereil Involucre-scales 4. Receptacle naked. 

 Pappus simple, capillary. Climbing herbs. 



29. BJDKSS. Heads many-flowered. Receptacle chaffy. Pappus consisting 

 cf K i, i-tiir, barbed awns. 



GEODP 7. 



Central flowers stamlnate ; marginal ones pistillate, fertile. 



88. IVA. Heads small, on short recurved peduncles, racemose, forming 

 leafy panicles. Shrubby at base. 



S. Central Jhncert tubular ; marginal or ray Jlowert ligulate. 

 a. Leave* all alternate or radical, 



GSOCP 8. 

 Rays yellow, pistillate. Disk-flowers perfect 



18. SOUDAQO. Heads small. Bays about 5, short. Involucre-scales Imbri- 

 ate. Keceptacle flattlsb, alveolate. 



14. fanu. Heads very large. Bay* very numerous. Involucre-sealer 

 imbricate. Receptacle flat 



21. IlELtNitn. Rays numerous, 3 S-cIeft at nunmlt Involucre of re- 

 flexed scales. Receptacle subgloboac, naked. 



80. SEXICIO. Heads In flat corymbs. InTolucre-scalea in a single row. 

 Kays entire. Receptacle flat 



GROUP 9. 



Rays not yellow, pistillate. Disk-flowers perfect 

 * Receptacle alveolate. 



6. ASTIR. Heads corymbose or paniculate. Pappus simple, capillary. 

 Achenla compressed, smooth. 



7. M-.KicocAKFi-i. Heads corymbose. Pappus simple, capillary. Achenla 

 obconic, densely iilky. 



8. DIPLOPAPPUS. Heads rather large, corymbose, or solitary. Involucre 

 scales appreased. Pappus double ; outer series very short; Inner of capillary 



89. CALENDULA. Involucre-scales nearly equal, in 2 rows. Pappus none. 

 b. Lower leave*, at least, opposite, 



GROUP 12. 



Rays pistillate. Disk-flowers perfect 



12. DAIIUA. Involucre-scales in 2 rows. Receptacle chaffy. Pappus 

 none. Leaves pinnate. 



16. llEudrsis. Involucre-scales Imbricated In several rows. Receptacle 

 chaffv, conical Pappus none. 



18. ZINM.V. Iiivulucre-scalee imbricated in several rows. P.eceptaclo 

 tiaffy, conical. Pappus of the disk consisting of 2 erect awus. Leaves entire. 



20. TAOETES. Involucre-scales in 1 row. Keceptacle naked. Pappus of 5 

 rect awns. Leaves pinnately-parted. 



GEOUP 13. 

 Rays neutral Disk-flowers perfect 



19. IlELiAKTiirs. Involucre-scales In several rows. Receptacle with pcr- 

 Istent chaff. Pappus persistent, of 2 deciduous, chaffy awns. 



28. COREOPSIS. Involucre-scales in 2 series. Receptacle with deciduous 

 chaff. Acbenia compressed. Pappus reduced to 2 teeth, or none. 



29. BIDENS. Involucre-scales in 2 series. Receptacle chaffy. Pappus con- 

 istiug of 2 4 barbeil awns. Achenia quadrangular. 



SUBORDER II. Lignlifloroj. 

 Flowers all ligulate. 



GROUP 1. 

 Plants acanleftcent 



4->. KK'IOIA. Involucre-scales equal, in 2 rows. Achenla turbinate. Pap- 

 pus double ; outer series of broad scales ; inner of slender bristles. 



49. LEOXTODON. Involucre-scales imbricate; outer ones very short Pap- 

 lus plumose ; bristles in a single series, Achenia scarcely beaked. 



&&. TARAXACUM. Involucre-scales in 2 series; inner series appressed ; outer 

 reflexed. Achenla with a long beak, bearing a capillary, copious pappus. 



GROUP 2. 



Plants caulescent Heads yellow. 



68. HiiRAciuM. Achenla oblong, not beaked. Pappus-bristles tawny, ca- 

 pillary, in a single series. Leaves toothed or entire. 



51. LACTUOA. Acbenia compressed, with a long filiform beak. Pappus 

 verv abundant, white and soft 



6ft. BOXCHUS. Achenla compressed, not beaked: Pappus very abundant, 

 white, soft, capillary. 



GROUP 8. 



Plants caulescent. Heads not yellow. 



47. CicnORirK. Involucre-scales In 2 series. Pappus of very short scales. 

 Achenia not beaked. Leaves runcinate. 



50. TEAOOPOOOX. Involucre-scales in a single series. Achenia with a long, 

 filiform beak. Pappus plumose. Lefves linear. 



52 . Mi-uicmun. Inviiliicre-scales In 2 series; outer ones short Achenia 

 flattlsb, with short thick beaks. Pappus soft, capillary. 



54. NABAI.CS. Involucre-scales cylindric, In a single row, with a few ap- 

 pressed bracelets at base. Achenia not beaked. Heads mostly In axillary 

 racemes. 



1. VEP.N6NIA. 



Heads 15 many-flowered. Involucre of many ovate, up- 

 pressed, imbricated scales, shorter than the flowers. Receptacle 

 naked. Achenia cylindrical, ribbed. Pappus double ; the outer 

 short, chaffy ; the inner capillary. Per. 



10. CALLisTEpircs. Heads very large, solitary on the branchlets. Involucre 

 scales with large, leafy, spreading tips. Pappus double; outer aeries of short, 

 chaffy wales ; loner series of long capillary, deciduous bristles. 



- < LIDAOO. Heads small, In axillary racemes, Rays few, short Pap- 

 pas simple, capillary. 



* Receptacle naked. 



9. EatanoN. Ray flowers very numerous and narrow. Pappus simple or 

 double. Receptacle flat. 



11. BIUJS. Leaves all radical Heads solitary. Receptacle conical. Pap- 

 pas none. 



.rxcAJrrnrKuM. Involucre broad, depressed at the centre. Pappus 



i'vEcrnauM. Involucre hemispherical. Pappus reduced to a mem- 

 branous border or crown. 



27. CuiTsixTniiiuic. Involucre hemispherical. Pappus none. 

 Hi . i-plm ! chaffy. 

 22. A-miEHifl. Rays numerous. Receptacle convex. Pappus reduced to 

 ii- >nlng theachenla. 



IIII.LIA. Kays 510. Receptacle flat Pappus none. 



GROUP 10. 

 Kays neutral. Disk flowers perfect 



!iauTA. Receptacle conical, mor or less chaffy. Rays white. 

 17. RCDBECKIA. Involucre-scales In 2 series. Receptacle conical, chaffy 

 Pappus none, or a mere border. Bays yellow. 



< 11. 



Rays pistillate. Disk-flowers stamlnate. 

 S. TcseiL.ino. Acanlescent Rays very narrow, In many rowa. 



1. V. Noveboracensis. 



Iron-weed. 



Stem erect, branching above ; leaves alternate, lanceolate, serrulate, pubes- 

 cent underneath ; heads rather large, dark purple, in terminal, compound, flat- 

 topped cymes ; scales of the Involucre terminating in a long awn, or bristle- 

 like appendage. A tall plant, 4 6 feet high, in swamps, with numerous dark 

 purple heads. Quite showy. Aug. Sep. 



2. EUPAT6RIUM. 



Heads 8 many-flowered. Involucre cylindrical, imbricate, 

 Receptacle flat Style much exscrt. Pappus simple, roughish. 

 Achenia 5-angled. Per. 



\. E. purpureum. Trumpet-weed. 



Stem tall, simple ; leaves varying from broad-ovate to lanceolate, acuminate, 

 veiny, somewhat rough, serrate or toothed, 86 in a whorl ; heads 5 10-flow 

 ered ; scales of the Involucre purplish, numerous, closely Imbricated in several 

 rows of unequal length ; flowers light purple, In dense compound corymbs. An 

 exceedingly variable plant The stem ranges from 210 feet high, Is solid en 

 hollow, spotted or without spots, and sometimes dotted ; leaves also variable h 

 shape and size. Low ground. Very common. Aug. Sep. 



2. E. teucrifolium. 



Pubescent and somewhat rough ; loaves opposite, ovate or ovato-lanccolate. 

 obtuse at base, sessile, veiny ; upper ones alternate and nearly entire ; heads in 

 corymbs, with a few unequal branches, about 8-flowered, white : scan 



