GENUS 92. THISTLE FAMILY. 521 
3. Matricaria Chamomilla L. Wild or 
German Camomile. Fig. 4567. 
Matricaria Chamomilla L. Sp. Pl. 891. 1753. 
Annual, glabrous, much branched, 1°-2° high. 
Leaves aromatic, finely 2-3-pinnately dissected 
into numerous linear lobes; heads numerous, 
8-12” broad, slender-peduncled at the ends of 
the branches; bracts of the involucre oblong, 
obtuse, green, or with brownish margins; rays 
10-20, white, spreading; receptacle ovoid, be- 
coming conic and hollow; achenes nearly oblong, 
or somewhat obovoid, faintly 3-5-ribbed; pappus 
none, 
Tn waste places and on ballast, southern New York 
to Pennsylvania. Adventive or fugitive from Eu- 
rope. Horse-gowan, Summer. 
4. Matricaria matricarioides (Less.) 
Porter. Rayless Camomile. Wild 
Marigold. 4568. 
Santolina suaveolens Pursh, Fl. Am. Sept. 520. 
18142 Not M. suaveolens L. 1755. 
eee matricarioides Less. Linnaea 6: 210. 
1831, 
Matricaria discoidea DC. Prodr. 6: 50. 1837. 
Matricaria matricaricides Porter, Mem. Torr. 
Club 5: 341. 1804. - 
AM. suaveolens Buchenau, Fl. Nord. Tief. 496. 
1894. 
Annual, glabrous; stem very leafy, at length 
much branched, 6-18’ high. Leaves 2-3-pin- 
nately dissected into linear acute lobes; heads 
numerous, 3-4” broad, peduncled; bracts of 
the involucre oval or oblong, green, with 
broad white scarious margins, much shorter 
than the ovoid yellow disk; rays none; recep- 
tacle conic; achenes oblong, slightly angular, 
faintly nerved; pappus an obscure crown, 
sometimes produced into 2 coriaceous oblique 
auricles. 
In waste places, in ballast and along railroads, 
Missouri to Massachusetts and Maine. Adven- 
tive from the Pacific coast. Naturalized as a 
weed in northern Europe. May-Aug. 
93. TANACETUM [Tourn.] L. Sp. Pl. 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 cam- 
panulate, 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 obtuse and 
entire at the base, their tips broad. Style-branches truncate and penicillate at the summit. 
Achenes s-angled or 5-ribbed, truncate or obtuse. Pappus none, or a short crown. [From 
tanasie, old French for tansy; Greek, athanasia, immortality.] 
About 30 species, natives of the northern hemisphere. Besides the following, another occurs 
in California. Type species: Tanacetiom vulgare L. 
Glabrous, or nearly so; heads numerous, 3”-5” broad. 1. Ti cnulgare. 
Villous-pubescent ; heads few, 6”-8” broad. . 2. T. huronense. 
