290 COMPOSITE, (composite family.) 



70. TANACETUM, L. Taxsy. 



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

 pistillate and 3-5-tootlied. Involucre imbricated, dry. Receptacle convex 

 naked. Achenes angled or ribbed, with a large flat top ; pappus a short crown. 

 — Bitter and acrid strong scented herbs (ours perennial), with 1 -3-pinnately 

 dissected leaves, and corymbed heads. Flowers yellow; in summer. (Name 

 of uncertain derivation.) 



T. vulgXre, L. (Commox Tansy.) Stem (2-4° high) smooth; leaf- 

 lets and the wings of the petiole cut-toothed ; corymb dense ; pistillate flowers 

 terete, with oblique 3-toothed limb; pappus 5-lobed. — Var. CRisrr:M has the 

 leaves more cut and crisped. — Escaped from gardens to roadsides ; Atlantic 

 States. (Nat. from Eu.) 



1. T. Huronense, Nutt. Hairy or woolly when young, stout (1-3° 

 high); lobes of the leaves oblong; heads large (i-f wide) and usually few; 

 pistillate flowers flattened, 3-5-cleft; pappus toothed. — St. John's River, 

 Maine ( G. L. Goodale), shores of the upper Great Lakes, and westward. 



71. ARTEMISIA, L. Wormwood. 



Heads discoid, few - many-flowered ; flowers all tubular, the marginal ones 

 pistillate, or sometimes all similar and perfect. Involucre imbricated, dry and 

 scarious. Receptable small and flattish, naked. Achenes obovoid, with a 

 small summit and no pappus. — Herbs or shrubby plants, bitter and aromatic, 

 with small commonly nodding heads in panicled spikes or racemes ; flowering 

 in summer. Corolla yellow or purplish. (Ancient name of the Mugwort, in 

 memory of Artemisia, wife of Mausolus.) 



§ 1. Receptacle smooth ; marginal flowers pistillate and fertile ; disTcflowers per- 

 fect but sterile, the sti/le mostly entire ; root perennial, except in n. 1. 

 * Leaves dissected. 



1. A. eaudata, Michx. Smooth (2-5° high); upper leaves pinnately, 

 the lower 2- 3-pinuately divided ; the divisions thread form, diverging; heads 

 small, the racemes in a wand-like elongated panicle ; root biennial. — Sandy soil, 

 coast of N. H. to Va. ; also Mich, to Minn., and southward. 



2. A. Canadensis, Michx. Smooth, or hoary with silky down (1-2° 

 high) ; lower leaves twice-pinnately divided, the upper 3 - 7-divided, the divi- 

 sions linear, rather rigid ; heads rather large, in panicled racemes. — Northern 

 N. Eng. to the Great Lakes, Minn., and northward. (Eu.) 



* * Leaves entire or some 3-cleft. 



3. A. dracunculoides, Pursh. Tall (2-5°), somewhat woody at base, 

 slightly hoary or glabrous ; leaves linear and entire or the lower 3-cleft ; lieads 

 small and numerous, panicled. — Sandy banks of streams, Minn, to 111., Mo., 

 and westAvard. 



4. A. glaiica, Pall. Strict, 1-2° high, somewhat Avoody at base, minutely 

 silky-pubescent or glabrate ; leaves linear- to oblong-lanceolate ; heads as in 

 the last. — Sask. to Minn. (Sib.) 



5. A. filif61ia, Torr. Suffruticose, finely canescent, 1-3° high; leaves 

 all filiform, the lower commonly 3-parted ; heads very small and numerous, 

 crowded in a long leafy panicle. — Central Kan. to Neb., and southwestward. 



