460 



COMPOSITAE. 



[Vol. III. 



4. Matricaria matricarioides 



(Less.) Porter. Rayless Camomile. 



(Fig. 3995O 



Santolina suaveolens Pursh, Fl. Am. Sept. 



520. 1814. Not M. suaveolens L. 1755. 

 Artemisia matricarioides Less. Linnaea, 6: 



210. 1831. 

 Matricaria discoidea DC. Prodr. 6: 50. 1837. 

 Matricaria tnatricarioides Porter. Mem. Torr. 



Club, 5: 341. 1894. 



Annual, glabrous; stem very leafy, at 

 length much branched, 6 / -iS / high. Leaves 

 2-3-pinnately dissected into linear acute 

 lobes; heads numerous, 3 // -4 // broad, pe- 

 duncled; bracts of the involucre oval or ob- 

 long, green with broad white scarious mar- 

 gins, much shorter than the ovoid yellow 

 disk; rays none; receptacle conic; achenes 

 oblong, slightly angular, faintly nerved, 

 pappus an obscure crown, sometimes pro- 

 duced into 2 coriaceous oblique auricles. 



In waste places, in ballast and along rail- 

 roads, Missouri to Maine. Adventive from 

 the Pacific coast. Naturalized as a weed in 

 northern Europe. May-Aug. 



87. TANACETUM L,. Sp. PI. 843. 1753. 



Erect, strongly aromatic herbs, our species perennials, with alternate, 1-3-pinnately dis- 

 sected or divided leaves, and numerous small corymbose heads of tubular flowers, or with 

 rays sometimes present and imperfectly developed. Involucre hemispheric, depressed, or 

 campanulate, its bracts appressed, imbricated in several series. Receptacle flat or convex, 

 naked. Marginal flowers pistillate, fertile, their corollas 2-5-toothed or lobed, sometimes 

 produced into short rays. Disk-flowers perfect, fertile, their corollas 5-toothed. Anthers ob- 

 tuse and entire at the base, their tips broad. Style-branches truncate and penicillate at the 

 summit. Achenes 5-angled or 5-ribbed, truncate or obtuse. Pappus none, or a short crown. 

 [From tanasie, old French for tansy; Greek, athanasia, immortality.] 



About 35 species, natives of the northern hemisphere. Besides the following, 6 others occur 

 in western and northwestern North America. 

 Glabrous, or nearly so; heads numerous, 3" -5' 

 Villous-pubescent; heads few, 6" -8'' 



broad. 



broad. 



T. mi Iff a re. 

 T. Huronense. 



i. Tanacetum vulgare L, 



Tanacetum vulgare L. Sp. PI. 844. 1753. 



Stem stout, usually simple up to the in- 

 florescence,glabrous,or sparingly pubescent, 

 i^2-3 high. Leaves pinnately divided 

 into linear-oblong, pinnatifid or incised seg- 

 ments, the lobes acute, usually serrate; 

 lower segments of the leaves often smaller 

 than the others; basal leaves often i long; 

 heads commonly numerous, 3 // ~5 // broad, 

 rather short-peduncled ; involucre depressed- 

 hemispheric, its bracts oblong-lanceolate, 

 obtuse, or the outer acute, slightly pubes- 

 cent or ciliate; receptacle fiat; flowers yel- 

 low; marginal corollas with short oblique 

 3-toothed limbs; pappus a short crown. 



Along roadsides, mostly escaped from gar- 

 dens, Nova Scotia and Ontario to Minnesota, 

 south to North Carolina and Missouri. Natu- 

 ralized or adventive from Europe. Other Eng- 

 lish names are Bitter Buttons, Hindheal, Gin- 

 ger-plant., July-Sept. 



Tanacetum vulgare crispum DC. Prodr. 6: 128. 



l8 37; . 



Leaf-segments more incised and crisped. 

 Occasional, in similar situations. In some 

 places more plentiful than the type. 



Tansy. (Fig. 3996.) 



