242 COMPOSITJE. (composite family.; 



65. ACHILLEA, L. Yarrow. 



Heads many-flowered ; the rays pistillate, few and short. Scales of the inro- 

 lucre imbricated. Receptacle flat or elon<^ated, chaff'y. Achenia oblong, com- 

 pressed, margined. Pappus none. — Perennial herbs. Leaves alternate, com- 

 monly pinnatcly divided. Heads small, corymbose. 



1. A. millefolium, L. Stems (1° high) simple, pubescent, tufted; leaves 

 lanceolate, bipinnatifid, the divisions linear, 3 - 5-cleft ; corymbs dense, compound ; 

 rays 4-5, white. — Old fields and around dwellings. Introduced. May -Sept. 



66. LEUCANTHEMUM, Toum. O.v-ete Daisy. 



Heads many-flowered ; the rays numerous, pistillate. Scales of the involucre 

 imbricated, broad, rounded, with scarious margins. Receptacle flat or convex, 

 naked. Achenia nearly terete. Pappus none. — Perennial herbs. Leaves alter- 

 nate, toothed or pinnatifid. Heads solitary, terminating the stem or branches. 

 Rays white. 



1. L. VUlgare, Lam. Stem (6'- 12' high) simple, naked above; leaves 

 pinnatifid ; the lowest spatulate-obovatc ; the upper lanceolate ; heads showy. 

 (Chrysanthemum Leucanthemum, L) — Fields. Introduced. May and June. 



67. TANACETUM, L. Taksy. 



Heads many-flowered, discoid ; the flowers all fertile ; the marginal ones chiefly 

 pistillate, 3-5-toothed. Scales of the involucre imbricated, dry. Receptacle 

 convex, naked. Achenia angled or ribbed. Pappus a narrow border, or none. 

 — Herbs with alternate dissected leaves, and solitary or corymbose heads of 

 yellow flowers. 



1. T. VUlgare, L. Stem smooth, erect; leaves bipinnately divided, the 

 lobes serrate ; heads corymbose, numerous ; pappus 5-lobed. — Common in 

 gardens, and sparingly naturalized in North Carolina, y. — Stem 1° - 2° high. 



68. ARTEMISIA, L. WoRMwoon. 



Heads few- or many-flowered, discoid ; the central flowers perfect, 5-toothed 

 (sometimes abortive), the marginal ones pistillate, 3-toothed. Scales of the in- 

 volucre imbricated, mostly with scarious margins. Receptacle convex, naked 

 or villous. Achenia obovoid. Pappus none. — Aromatic herbs or shrubs. 

 Leaves alternate, pinnately divided. Heads small, in panicled spikes or racemes. 



1. A. caudata, Michx. Smooth; stem slender, branching ; lowest leaves 

 2 -3-pinnately divided, the upper ones pinnate, with the divisions filiform ; heads 

 globular, in small racemes, forming an elongated panicle. — Dry open woods, 

 West Florida, and northward. Sept. (§) — Stem 2° -6° high. Receptacle 

 naked. Disk-flowers abortive. 



69. SOLIVA, Ruiz & Pavon. 



Heads many-flowered, monoecious ; the fertile flowers in several rows, apeta- 

 lous or nearly so ; the staminate few in the centre, with a 3- 6-toothed corolla. 



