Genus 91. 



THISTLE FAMILY. 



5'9 



3. Chrysanthemum segetum L. Yellow Ox- 

 eye. Corn Marigold. Fig. 4562. 



Chrysanthemum segetum L. Sp. PI. S89. 1753. 



Annual, glabrous, ll high or less. Leaves oblong 

 to oblanceolate, the upper auriculate-clasping, the 

 lower petioled, dentate, incised, or nearly entire, 3' 

 long or less; heads about i broad; involucral bracts 

 obtuse, scarious ; rays obovate, yellow, emarginate ; 

 pappus a mere margin. 



Waste grounds. New York, New Jersey, and in ballast 

 about the seaports. Adventive from Europe. 



Chrysanthemum coronarium L., also European, with 

 yellow rays and bipinnatifid leaves, has been found in 

 Ontario. 



4. Chrysanthemum Parthenium (L.) 

 Pers. Common Feverfew. Feather- 

 few. Fig. 4563. 



Matricaria Parthenium L. Sp. PI. 890. 1753. 

 C. Parthenium Pers. Syn. 2: 462. 1807. 



Perennial ; stem puberulent or glabrate, much 

 branched, l-2i high. Leaves thin, the lower 

 often 6' long, petioled, or the upper sessile, 

 pinnately parted into ovate or oblong, pinna- 

 tifid or incised segments ; heads numerous, co- 

 rymbose, slender-peduncled, 6"-io" broad ; 

 bracts of the depressed involucre lanceolate, 

 rather rigid, keeled, pubescent, acute or acutish ; 

 rays 10-20, white, oval or obovate, spreading, 

 mostly toothed, long-persistent; pappus a short 

 toothed crown. 



In waste places, New Brunswick and Ontario to 

 New Jersey, Ohio, and in California, mostly es- 

 caped from gardens. Naturalized or adventive 

 from Europe. Called also pellitory, wild camo- 

 mile. Rays variable in length. Summer. 



5. Chrysanthemum Balsamita L. Cost- 

 mary. Mint Geranium. Fig. 4564. 



C. Balsamita L. Sp. PI. Ed. 2, 1252. 1763. 

 Pyrethrum Balsamita Willd. Sp. PI. 3 : 2153. 1804. 



Perennial, puberulent or 

 much branched, 2-4 high 



canescent ; stem 

 Leaves oblong, 

 obtuse, crenate-dent'ate, i'-2' long, those of the 

 stem mostly sessile, and often with a pair of 

 lateral lobes at the base ; heads numerous, co- 

 rymbose, slender-peduncled, 5"-8" broad, or 

 when rayless only 3" broad ; bracts of the in- 

 volucre narrow, obtuse, pubescent; rays 10-15, 

 white, spreading ; pappus a short crown. 



Sparingly escaped from gardens, Ohio to Mich- 

 igan, Ontario and Nova Scotia. Native of the Old 

 World. Other English names are cost, alecost, ale- 

 coast. Summer. 



