COMPOSITE. (COMPOSITE FAMILY.) 227 



1. T. VULGARE, L. (COMMON TANSY.) Stem erect, smooth; leaves 

 twice-pinnately parted, the leaflets and the margined petiole cut-toothed ; cor- 

 ymb dense ; pistillate flowers terete ; pappus 5-lobed. Var. cat SPUM has the 

 leaves more cut and crisped. ]| Escaped from gardens. (Adv. from Eu.) 



2. T. Huronense, Nutt. Hairy or woolly when young, stout (l-3 

 high); leaves 2 - 3-pinnately dissected, the lobes oblong; heads large ('- 

 wide) and usually few; pistillate flowers flattened, 3 - 5-cleft ; pappus toothed. 

 U Shores of L. Huron, Superior, and northwestward. 



57. ARTEMISIA, L. WORMWOOD. 



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

 ones pistillate, or sometimes all similar and perfect. Scales of the involucre 

 imbricated, with dry and scarious margins. Receptacle small and flattish, na- 

 ked. Achenia obovoid, with a small summit and no pappus. Herbs or shrubby 

 plants, bitter and aromatic, with small heads in panicled spikes or racemes. 

 Corolla yellow or purplish. (Dedicated to Artemis, the Greek Diana.) 



1 . Receptacle smooth : marginal flowers pistillate and fertile : disk-flowers sterile. 



1. A. borealis, Pallas. Low (3' -6' high), tufted, silky-villous or nearly 

 smooth ; lower leaves 3 - 5-cleft at the apex, or like the others 1 - 2-pinnately parted, 

 the lobes lanceolate or linear ; heads few, hemispherical, pretty large, spiked or 

 racemed. ]\. Shore of Lake Superior and northward. (Eu.) 



2. A. Canadcnsis, Michx. (CANADA WORMWOOD.) Smooth, or 

 hoary with silky down (l-2 high) ; lower leaves twice-pinnately divided, the 

 upper 3 - 7-dividcd ; the divisions linear, rather rigid; heads rather large in pani- 

 cled racemes. 1J. Shore of all the Great Lakes, and northward. (Eu.) 



3. A. caudata, Michx. (SLENDER WORMWOOD.) Smooth (2 -5 

 high); upper leaves pinnately, the lower 2 - 3-pinnately divided ; the divisions 

 thread-form, spreading ; heads small, the racemes in a wand-like elongated panicle. 

 Sandy soil, coast of New Hampshire to New Jersey ; and in Illinois. 



2. Receptacle smooth : flowers all fertile, a few pistillate, the others perfect. 



4. A. Ludoviciana, Nutt. (WESTERN MUGWORT.) Whitened-wooL 

 ly throughout, branched (l-5 high) ; leaves lanceolate, the lower mostly cut- 

 toothed or pinnatifid, the upper mostly entire, the upper surface often becoming 

 naked and smooth with age ; heads ovoid, mostly sessile, disposed in narrow 

 leafy panicles. 1J. Dry banks, Lakes Huron and Michigan, and westward; 

 especially the var. GNAPHAI^DES, which has the elongated nearly entire leaves 

 very woolly both sides. 



5. A. VULGA.RIS, L. (COMMON MUGWORT.) Branches and lower sur- 

 face of the leaves whitish-woolly ;. stem-leaves pinnatifid , with the lobes variously cut 

 or entire, linear-lanceolate; heads ovoid, in open leafy panicles, 1J. Waste places, 

 near dwellings. (Adv. from Eu.) 



6. A. biennis, Willd. (BIENNIAL WORMWOOD.) Smooth, simple (1 

 -3 high); lower leaves twice-pinnately parted, the upper pinnatijid; lobes linear, 

 acute, in the lower leaves cut-toothed ; heads in short axillary spikes, which are 



