406 THE KINDS OF PLANTS 



distinct and leaf -like, the inner united at base: receptacle chaflfy: pappus 

 none. In the big cultivated dahlias, most of the flowers are rays. 



D. variflbilis, Desf. Fig. 232. Several feet, with fine large heads of 

 flowers, colors various: heads solitary: leaves pinnate, leaflets unequal, 

 3-7, ovate acuminate, coarsely serrate. Mexico. 



11. C6SM0S. 



Handsome tall plants, 4-5 ft. high, cultivated for the fine foliage and late 

 flowers: leaves opposite, very finely dissected, thrice-compound, the leaflets 

 extremely narrow, and sessile: flower head with double involucre: the outer 

 bracts dark green, calyx-like, 8 in number, the inner scales erect, with 

 recurved tips: ray flowers, usually 8, neutral, white, pink: disk flowers per- 

 fect, tubular, yellow: receptacle chafi'y: akenes flattened, beaked. Mexico. 



C. bipinn^tus, Cav. Rays 1 2 in. long, crimson, rose or white, the disk 

 yellow. The commonest species. 



C. sulphureus, Cav. Both rays and disk yellow. 



12. ACHILLEA. Yarrow. 



Low perennial or annual herbs: heads corymbose, many-flowered, white 

 or rose, with fertile rays : scales of involucre overlapping ( imbricated) : torus 

 flattish, chaflfy: pappus none. 



A. Millefdlium, Linn. Farrow. Stems simple below, but branching at 

 the top into a large rather dense umbel-like flower cluster: leaves very dark 

 green, twieepinnatified into very fine divisions : rays 4-5. Fields everywhere. 



13. ANTHEMIS. Chamomile. 



Strong-scented, branching herbs with finely pinnatified leaves and 

 raany-flowered heads, solitary on peduncles: ray flowers white or yellow, 

 pistillate or neutral, the edge of corolla entire or 2- to 3-toothed : disk flowers 

 perfect, fertile, yellow, corolla 5cleft: receptacle convex, partially chaflfy: 

 involucral bracts small, dry, in several series, outermost shortest: akenes 

 round or ribbed, smooth: pappus none or a slight border. 



A. Cdtula, DC. May-weed. Annual, bushy, erect, 1-2 ft.: heads ter- 

 minal, corymbed, 1 in. broad: rays usually white, neutral: disk flowers yel- 

 low: leaves alternate, mostly sessile, finely pinnatified. Roadsides. Europe. 



14. CALENDULA. Pot Marigold. 



Erect, quick-growing annuals, with terminal large yellow or orange heads 

 with pistillate rays: involucre of many short green scales: torus flat: pap- 

 pus none: akenes of the ray florets (those of the disk florets do not mature) 

 curved or coiled. 



C officinalis, Linn. Common pot marigold. A common garden annual 

 from the Old World, with alternate entire sessile oblong leaves: 1-2 ft. 



15. CHRYSANTHEMUM. Chrysanthemum. 



Erect herbs, annual or perennial, with alternate lobed or divided leaves i 

 rays numerous, pistillate and ripening seeds: torus usually naked, flat or 

 convex: pappus none, 



