Class XIX. Order III. 315 



The road sides are full of the white blossoms of this common, 

 annual weed, from midsummer to the end of autumn. Stem up- 

 right, smooth, much branched. Leaves alternate, sessile, nearly 

 smooth, divided and subdivided into linear segments. Flower 

 stalks solitary, striated. Calyx scales narrow, slightly margined. 

 Florets of the ray white, spreading, a dozen or more in number. 

 Disc yellow, convex. Receptacle nearly cylindrical. The plant 

 has a strong, peculiar smell, and reputed medicinal virtues. 



325. ACHILLEA. 

 ACHILLEA MILLEFOLIUM L. Common Yarrow. 



Leaves bipinnatifid, hairy, their divisions linear, 

 toothed, mucronate ; stems furrowed. Sm. 



Common Yarrow is a frequent inhabitant of dry pastures and 

 fields. Stem erect, furrowed, hairy, branched at top. Leaves 

 alternate, cut into a multitude of very small, linear subdivisions. 

 Flowers white, forming a large, flat topped, crowded corymb. 

 Calyx ovate. Disc convex. Florets of the ray four or five. 

 The plant has a strong, penetrating taste and smell, and is used 

 medicinally. July, August. Perennial. 



FRUSTRJ1NEJ1. 



326. HELIANTHUS. 

 HELIANTHUS DIVARICATUS. L. Small, rough Sunflower. 



Leaves opposite, sessile, ovate-oblong, three nerved ; 

 panicle dichotomous. L. 



A shewy plant, not uncommon in woods and thickets, flower- 

 ing in August and September. Stem erect, round, smooth, gene- 

 rally covered with glaucous powder. Leaves opposite, narrow- 

 ovate, rounded at base, tapering to a long point, slightly serrate, 

 three nerved, and very rough. Flowers yellow, in the wild 

 plant but few in number, in the cultivated one numerous. Branch- 

 es of the panicle either forked or three parted. Perennial. 



This plant has an agreeable, somewhat spicy odour. 



327. COREOPSIS. 



COREOPSIS TRICHOSPERMA. Mich. Tickseed Sunjioiver. 



Leaves mostly live pinnate ; leafets lanceolate ; re- 



