206 COMPOSITAE 



40. TANACETUM L. 



Perenuials with alternate pinuatitid leaves and corymbose heads. In- 

 volucre imbricated. Mar<^iual tlowers fertile. Pappus a short crown. 



1. T. vulgare L. Tansv. Smootbish, l°-4° high : heads about V^ 

 broad : marginal flowers with short 3-toothed limbs. — Occasionally escap- 

 ing from gardens to roadsides. August -September. 



41. ARTEMISIA L. Wormwood. 

 Alternate-leaved herbs with small paniculate heads of flowers. Invo- 

 lucre imbricated. Pappus none. 



Leaves glabrous or nearh' so on both sides. 



Upper leaves linear, entire. 1. A. dracunculoidcs. 



Upper leaves pinnately parted. 

 Plant strongly sweet-scented. 2. A. (tnnita. 



Plant not sweet-scented. 3. .1. biennis. 



Leaves strongly tomentose on both sides. 



Leaves pinnatifld. 4. A. Canidhii. 



Leaves entire. 5. A. gnaphalodes. 



Leaves glabrate above ; tomentose beneath. 



Stem strongly tomentose. 6, A. Ludoviciana. 



Stem glabrate. 7. A. 3Iexiccuia. 



1. A. dracunculoidcs Pursh. Perennial, l.>°-4° high, glabrous: 

 lower leaves somewhat pinnatifld : disk flowers sterile. — Occurs locally 

 in barrens east of Dodson and west and north of Lee's Summit. August- 

 October. 



2. A. annua L. Annual, l°-5° high, glabrous : leaves 2-pinnatifid : 

 heads paniculate : flowers all fertile. — Sparingly adventized at Kansas 

 City and Independence. August-November. 



3. A. biennis Willd. Annual or biennial, l°-3° high, glabrous : 

 leaves once pinnatifld, the divisions serrate : heads almost spicate : flow- 

 ers all fertile. — Shore of the Missouri River ; rather infrequent. August- 

 November. 



4. A. Carruthii Wood. 12^-18' high, much branched, short white- 

 canescent : lower leaves pinnatifld into 5-7 narrowly linear segments : 

 upper leaves linear, entire : flowers all fertile. — Occurs rarely as a waif 

 at Sheffield. September-October. (4. A'ansano Britton.) 



5. A. gnaphalodes Nutt. Perennial, l°-3° high : stems tomentose: 

 upper leaves lanceolate or linear-lanceolate, entire : lower leaves more or 

 less incised but not pinnatifld: flowers all fertile: involucre hardly 

 tomentose-canescent : heads usually not nodding, lA" long. — Sandy bot- 

 toms along the Missouri River near Courtney and Sibley. Not common. 

 July-October. 



6. A. Ludoviciana Nutt. Stems 15'-30^ high, stout, densely white- 

 tomentose : leaves as in A. Mexicana Willd.: heads often nodding, 2'^ 

 long : involucre densely white tomentose-canescent. — Dry barrens and 

 prairies throughout the southern part. September-October. 



