172 



ORDER LXIV. COMPOSITE COMPOSITE-FAMILY. 



1. C. officinalis. 



Pot-Marigold. 



Viscid-pubescent; stem erect, branching ; leaves oblong, acute, mucronate, 

 sessile, somewhat toothed, ciliate, scabrous on the margin ; heads few, large, 

 terminal, solitary. A handsome annual, common in gardens, generally with 

 orange-colored, often double flowers. 



40. CENTAtTREA. 



Heads many-flowered. Flowers all tubular; marginal ones 

 mostly enlarged and sterile, resembling ray-flowers. Involucre 

 imbricate. Receptacle bristly. An. 



1. C. Cyanus. 



Bachelors Button. 



Stem erect, branching, downy ; leaves linear, sessile, downy ; heads solitary, 

 ovoid ; sterile flowers longer than the disk ; involucre-scales fringed. A com- 

 mon garden annual, sometimes naturalized along road-sides, generally with light 

 blue flowers, but varying to purplish, or white. July. 



41. AMBERBOA. 



Heads discoid. Marginal flowers usually enlarged and sterile. 

 Involucre-scales imbricate. Pappus of oblong, or obovate scales, 

 sometimes small or none. An. 



1. A. moschata. 



Sweet Sultan. 



Lower leaves lyrately toothed ; involucre subglobose, smooth, with ovate 

 scales ; marginal flowers scarcely longer than the rest, not exceeding the disk; 

 beads purple, sometimes white. Gardens. July Oct. 



2. A. odorata. 



Yellow Sweet Sultan. 



Lower leaves somewhat broadly spatulate; upper ones lyrate at base ; mar- 

 ginal flowers enlarged, longer than the disk ; pappus chaffy, a little shorter than 

 the achenia ; heads yellow. A garden annual, sometimes varying to purple 

 flowers, and deeply pinnatifid leaves. July Oct. 



42. CARTHAMUS. 



Heads discoid. Flowers all tubular and perfect. Involucre 

 of imbricated scales; outer ones foliaceous. Receptacle with 

 setaceous chaff. Pappus none. Achenia 4-sided. An. 



1. C. tinctorius. Common Saffron. 



Stem smooth, oval, striate, branching ; leaves ovate-lanceolate, sessile, den- 

 ticulate, with spinose teeth, somewhat clasping, smooth and shining; heads 

 large, terminating the branches, orange-colored, with the numerous flowers long 

 and filiform. A common plant in gardens, sometimes used for dyeing. Stem 

 12 ft high. July. 



43. XERANTHEMUM. 



Heads discoid. Involucre hemispherical, with colored, opaque, 

 scarious scales, resembling rays. Receptacle chaffy. Pappus 

 chaffy and setaceous. An. 



1. X. annuum. 



Stem erect, branching ; leaves alternate, oblong-lanceolate, more or ess ob- 

 tuse, entire ; heads large, terminal, solitary ; involucre-scales, obtuse ; inner 

 ones radiant, spreading, lanceolate, obtuse. A very elegant garden annual, with 

 large, spreading involucre-scales, generally purple, but often of other colors, re- 

 sembling ray-flowers. The heads retain their beauty through the winter. 



44. ONOP6KPON. 



Heads discoid. Flowers all tubular, perfect. Involucre ven- 

 tricose, with coriaceous, imbricate, spreading, spinous scales. Re- 

 ceptacle deeply alveolate. Pappus copious, capillary, united at 

 base into a ring. Achenia 4-angled. Men. 



1. 0. Acanthium. Cotton Thistle. 



"Woolly; leaves oblong-ovate, decurrent, toothed, spinous; heads large, 

 purple, solitary ; involucre globose, white-downy, with spreading, linear-subu- 

 late scales. A fine thistle, 25 ft. high, covered throughout with cottony down. 

 Naturalized and common along road-sides. July. 



45. ClRSIUM. 



Heads discoid, many-flowered. Flowers all perfect. Involu- 

 cre-scales usually tipped with spines, imbricated in many rows. 

 Receptacle bristly. Pappus of capillary, plumose bristles united 

 in a ring at base. Achenia oblong, compressed, smooth. Bien. 

 except No. 1. 



1. C. arvense. 



Canada Thistle. 



Root creeping; stem erect, branching ; leaves pinnatifid, with spiny teeth, 

 smooth or somewhat downy beneath ; heads small, light purple, numerous, in 

 a terminal, loose panicle ; involucre-scales closely appressed, tipped with mi- 

 nute spines. A very common and exceedingly troublesome weed, f-preading 

 rapidly, by its creeping roots, over fields and meadows, and rendering them un- 

 productive. Stem 23 ft high. Introduced. July. 



2. C. discolor. 



Tall Thistle. 



Stein furrowed, hairy, leafy, branching; leaves pinnatifld, slightly hairy 

 above, covered with white wool beneath ; lobes divaricate, 2 3-cleft the seg 

 ments tipped with spines ; heads rather large, pale purple, solitary ; involucre- 

 scales appressed, tipped with spines. A tall thistle, 37 ft. high, not uncommon 

 in thickets and meadows. Aug. 



3. C. miiticum. 



Glutinous Thistle. 



Stem tall, slender, nearly or quite smooth, branching; leaves pinnatifld, 

 slightly hairy above, covered with thin white hairs beneath when young; 

 lobes divaricate, lanceolate, acute, incised, the tips armed with spines; heads 

 rather large, solitary, or nearly so. on the nearly naked branches; involucre- 

 scales ovate, unarmed, sometimes mueronate, webbed and glutinous at base. A 

 tall thistle, 3 1 ft. high, common in swamps and low grounds. Aug. Sep. 



4. C. lanceolatum. 



Common Thistle. 



Stem very branching, leafy ; leaves deeply pinnatifld, decnrrent, hispid above, 

 white and woolly beneath, with divaricate, spinescent segments ; heads large, 

 numerous, purple; involucre-scales spreading, lanceolate, tipped with long and 

 formidable spines. A very prickly thistle, 35 ft high, common along road- 

 sides and in waste places. Introduced. July Sep. 



5. C. pumilum. 



Pasture Thistle. 



Stem very stont, hairy, nearly or quite simple ; leaves pinnatifld, clasping at 

 base, green on both sides; segments variously lobed and cut, ciliate, spinose; 

 heads very large, 1' 3' in diameter, fragrant, about 1 8 in number, purple, 

 rarely whitish ; involucre-scales spinous. A very common thistle, 1 2 ft. high, 

 distinguished by its very large fragrant heads, growing in pastures and fields. 

 Aug. 



46. LiPPA. 



Heads discoid, many-flowered. Flowers all perfect. Involu- 

 cre globose, with appressed, imbricated scales, each tipped with 

 a subulate, hooked appendage. Receptacle bristly. Pappus 

 bristly, rough, deciduous. Achenia oblong, compressed. Per. 



1. L. major. Burdock. 



Stem low, stout, very branching ; radical leaves very large, cordate, on long 

 channelled, fleshy, petioles ; upper leaves ovate, much smaller; all more or less 

 woolly beneath, and undulate on the margin ; heads small, mostly in dense 

 clusters; corollas tubular, pink-colored, quite pretty; involucre-scales ending 

 in a long, firm bristle, with a hook at the end. A very common weed in waste 

 grounds, distinguished by its large root-leaves, as well as by the hooked invo- 

 lucre-scales, which attach themselves to every thing that passes. July Aug. 



47. CICHOUIUM. 



Heads many-flowered. Involucre double ; outer of 5 short, 

 leafy scales; the inner of 8 10. Receptacle chaffy. Pappus 

 short, chaffy. Achenia striate. Per. 



1. C. intybus. Succory. 



Stem terete, with several long, nearly simple branches ; lower leaves rnnci- 

 nate ; upper ones oblong or lanceolate, more or less clasping at base, slightly 

 dentate or entire, small and inconspicuous : heads 2 3 together, axillary, sessile, 

 light blue, showy ; corolla 5-toothed. A handsome plant, 2 3 feet high, natur- 

 alized in fields and road-sides, not uncommon In districts near the coast. July 



Sep. 



48. KRlGIA. 



Heads 8 20-flowered. Involucre-scales equal, in about 2 

 rows. Receptacle naked. Pappus double ; the outer of 5 broad 

 scales ; the inner of 5 bristles alternating with the exterior scales. 

 Achenia obconic. An. 



1. K. Virginica. 



Dwarf Dandelion. 



Acau!escent ; leaves lanceolate, or narrowly spatulate, often pinnatifid or 

 lyrate, smooth , the early ones roundish, entire ; scapes several, slender, I -flow- 

 ered, rarely forked, elongated after flowering ; heads small, yellow ; involucre 



