458 



COMPOSITAE. 



[Vol. III. 



3. Chrysanthemum Parthenium 



(L. ) Pers. Common Feverfew. 



Featherfew. (Fig. 3990.) 



MalHcaria Parthenium L. Sp. PI. 8go. 1753. 

 Chrvsanlliemum Parlhenium Pers. Syn. 2:462. 

 1807. 



Perennial; stem puberulent or glabrate, 

 much branched, i°-2>^° high. I^eaves thin, 

 the lower often 6' long, pelioled, or the 

 upper sessile, pinnately parted into ovate or 

 oblong, piunatifid or incised segments; heads 

 numerous, corj'mbose, slender-peduncled, 

 (>"-io" broad; bracts of the depressed invo- 

 lucre lanceolate, rather rigid, keeled, pubes- 

 cent, 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, and locally in the interior, mostly 

 escaped from gardens. Naturalized or adven- 

 tive from Europe. Called also Pellilory, Wild 

 Camomile. Rays variable in length. Summer. 



4. Chrysanthemum Balsamita L. 

 Costmary. (Fig. 3991.) 



Chrysanthemum Balsamita L. Sp. PI. Ed. 2, 

 1252. 1763. 



Pyrelhrum Balsamita Willd. Sp. PI. 3: 21S3. 

 1804. 



Perennial, puberulent or canescent; stem 

 much branched, 2°-4° high. Leaves oblong, 

 obtuse, crenate-dentate, i'-2' long, those of 

 the stem mostly sessile, and often with a pair 

 of lateral lobes at the base; heads numerous, 

 corymbose, slender-peduncled, 5"-S" broad, 

 or when ray less only 3" broad; bracts of 

 the involucre narrow, obtuse, pubescent; 

 rays 10-15, white, spreading; pappus a short 

 crown. 



Sparingly escaped from gardens, Ohio to On- 

 tario and Nova Scotia. Native of the Old World. 

 Other English names are Cost, .\lecost, .\lecoast. 

 Summer. 



86. MATRICARIA L. Sp. PI. 890. 1753. 

 Annual or perennial, mostly erect herbs, similar to some species of the preceding genus, 

 ■with alternate leaves, dissected into filiform or narrowly linear segments and lobes, and pe- 

 duncled heads of both tubular and radiate flowers, or rays wanting in some species. Invo- 

 lucre hemispheric, its bracts appressed, imbricated in few series, the outer shorter. Re- 

 ceptacle conic, elongated or hemispheric, naked. Rays, when present, white, pistillate and 

 fertile. Disk-flowers yellow, perfect, fertile, their corollas 4-5-toothed. Anthers obtuse and 

 entire at the base. St3'le-branches of the disk-flowers truncate, penicillate. Achenes 3-5- 

 ribbed. Pappus none, or a coroniform border. [Latin, matrix, from its medicinal viitues.] 



About 20 species, natives of the northern hemisphere and South .■Africa. The following are the 

 only ones known to occur in North America. 

 Rays present, white. 



Achenes obpyramidal. stroiiglj* 3 ribbed. 



Plant tall, much branched; bracts of the involucre green. i. 



Plant low. nearly simple, arctic: bracts dark brown or black. 2. 



-•Vchenes nearly terete, oblong, faintly 3-s-ribbed. 3. 



Rays none; achenes oblong, faintly nerved. 4. 



M. inodora. 

 M. grayidiflora. 

 M. Chamomiita. 

 Af. matricarioides. 



