CARDUACEAE 1299 



5. Artemisia bi6nnis Willd. Biennial, glabrous, inodorous, insipid. Stems 2-10 

 dm. tall, nearly simple or sparingly branched : leaves numerous ; blades once or twice (lin- 

 nately divided, the segments lanceolate or linear, incised-pinnatifid or pinnatifid : panicle- 

 branches ending in spike-like racemes : heads not drooping, crowded in axillary clusters : 

 involucres about 2 mm. high, with the central flowers perfect and fruit-producing ; bracts 

 oblong or oblong-lanceolate : achenes oblong or oblong-obovoid, barely 1 mm. long. 



In rocky soil, Nova Scotia to the Northwest Territory to Pennsylvania, Tennessee and Missouri, 

 mainly naturalized eastward. Summer and fall. 



6. Artemisia vulgaris L. Perennial, lanate-tomentose. Stems 3-12 dm. tall, pan- 

 iculately branched : leaves numerous ; blades various, twice pinnatifid or pinnately parted, 

 the segments lanceolate or linear : heads cylindric-campanulate : involucres 4-5 mm. high, 

 with the central flowers fruit-producing ; bracts oblong to oblong-lanceolate : achenes 1.5-2 

 mm. long. 



In waste places. Nova Scotia to Ontario, Michigan, New Jersey and Tennessee. Summer and fall 



7. Artemisia gnaphalodes Nutt. Perennial, lanate-tomentose. Stems 3-13 dm. 

 tall, more or less branched : leaves numerous ; blades oblong, linear or linear-lanceolate, 

 3-7 cm. long or those clustered in the axils shorter, all entire or incised-serrate, about 

 equally white-woolly or tomentose on both sides : heads numerous, loosely racemose, panic- 

 ulate at maturity, over 3 mm. in diameter : involucres oblong-campanulate ; bracts densely 

 woolly. 



On dry plains and prairies, Ontario to British Columbia, Texas and Mexico. Summer and fall. 



8. Artemisia Mexic^na Willd. Perennial, less densely pubescent than ^4. g'/iapAatorfes. 

 Stems 6-12 dm. tall, paniculately branched : leaves numerous ; blades linear to narrowly 

 lanceolate, entire or those of the lower leaves incisely 3-cleft, or pinnatifid to pinnately 3-5- 

 cleft, densely white woolly beneath, green and partially glabrous above : heads numerous, 

 about 2 mm. in diameter : involucres campanulate ; bracts canescent or woolly. 



On prairies or hillsides, Arkansas to Arizona and Mexico. Summer and fall. 



136. SOLIVA R. & P. 



Annual caulescent herbs low in habit. Leaves mainly alternate : blades pinnately 

 dissected, petioled : heads heterogaraous, discoid, sessile in the axils. Involucres thick : 

 bracts about equal, 5-12 in 1 or 2 series. Receptacle flat. Flowers mainly pistillate, and 

 without corollas, few, perfect, commonly at the center of the disk. Corollas greenish. An- 

 thers obtuse at the base. Achenes flattened, with firm wings or callous margins, these 

 terminating in spines, the persistent style spine-like. Pappus wanting. 



1. Soliva nasturtiifolia (Juss. ) DC. Foliage minutely pubescent. Stems very 

 short : leaf-blades 4-10 mm. long, pinnately parted into 5-9 oblong or linear, entire or few- 

 toothed segments ; petioles as long as tlie blades or longer : heads not showy, subglobose, 

 3-6 mm. in diameter : involucral bracts linear to linear-spatulate, 2-2.5 mm. long : achenes 

 numerous, cuneate, 1.5-2 mm. long, the margins thickened and tubercular-rugose. 



In waste places. North Carolina to Florida. 



137. HAPLOESTHES A. Gray. 

 Perennial caulescent, partly woody and partly fleshy plants. Leaves opposite : blades 

 narrow, entire, the lower connate-sheatiiing. Heads corymbose, heterognmous, radiate. 

 Involucre of few broad many-nerved bracts. Receptacle flat or slightly convex, naked. 

 Ray-flowers pistillate, fruit-producing, with yellow ligules. Disk-flowers perfect, fruit- 

 producing. Anthers obtuse and entire at the base. Stigmas of the disk-flowers capitate- 

 truncate. Achenes narrow, 10-ribbed. Pappus of 1 series of slender scabrous bristles. 



1. Haploesthes Gr6ggii A. Gray. Stems usually branched at the base, the branches 3- 

 6 dm. tall, glabrous, striate, corymbose above : leaves fleshy, the lower ones connate and 

 sheathing the stem ; blades narrowly linear or linear-filiform, 2-4 cm. long, entire : heads 

 short-peduncled, few together in cymes : involucres 3-3.5 mm. high ; bracts few, oval to 

 orbicular, rounded at the apex, thin-margined : ligules of the ray-flowers yellow, 2-4 mm. 

 long : achenes 2 mm. long. 



In saline soil, southeastern Colorado to Texas and adjacent Mexico. Spring to fall. 



138. ARNICA L. 



Perennial caulescent herbs, with simple or sparingly branched stems. Leaves normally 

 opposite, sometimes mainly basal : blades flat, entire or toothed. Heads peduncled, radi - 

 ate or rarely discoid, solitary or several. Involucres many-flowered : bracts narrow, nearly 



