848 COMPOSITAE (COMPOSITE FAMILY) 



with 2 small lateral lobes at base ; heads rayless. — Frequently escaped from 

 gardens. (Introd. from Asia.) 



71. TANACETUM L. Tansy 



Heads many-flowered, nearly discoid ; flowers all fertile, the marginal chiefly 

 pistillate and 3-5-toothed. Involucre imbricated, dry. Receptacle convex, 

 naked. Achenes angled or ribbed, with a large flat top ; pappus a short crown. 



Bitter and acrid mostly strong-scented herbs (ours perennial), with 1-3- 



pinnately dissected leaves, and corynibed (rarely single) heads. Mowers yellow, 

 in summer. (Name of uncertain derivation.) 



1. T. vulgXre L. (CoMMOx T.) Stem 0.5-1 m.high, smooth; leaflets and 

 the wings of the petiole cut-toothed ; corymb dense ; pistillate flowers terete, 

 with oblique 3-toothed limb ; pappus 6-lobed. — Escaped from gardens to road- 

 sides, etc. (Introd. from Eu.) Var. crIspum DC. Leaves more cut and crisped. 

 — Frequent in similar places. (Introd. from Eu.) 



2. T. huronlnse Nutt. Hairy or looolly when young, stout, 3-9 dm. high ; 

 lobes of leaves oblong; heads large (1-2 cm. wide) and usually /ew? ; pistillate 

 flowers flattened, .3-5-clef t ; pappus toothed. — River-banks, e. Que. to N. B. and 

 n. Me. ; shores of the upper Great Lakes ; coast of Ore., Wash., and B. C. 



72. c6tULA [Tourn.] L. 



Heads hemispherical to globose, many-flowered, discoid ; the marginal flowers 

 (reduced rays) pistillate and fertile, nearly or quite apetalous ; disk-flowers 

 tubular, 4-toothed, fertile. Chaff none. Achenes at maturity mised on pedi- 

 cels, which remain attached to the flat or moderately convex receptacle. Pappus 

 obsolete or none. — Low mostly diffuse or creeping strong-scented herbs, with 

 alternate toothed, lobed, or dissected leaves, and pedunculate heads of yellow 

 flowers. (Name from kotvXt], a small cup, alluding to the hollow at the base of 

 the amplexicaul leaves.) 



1. C. coronopif6lia L. Branched from the base, decumbent and often 

 somewhat repent, slightly fleshy, nearly or quite smooth ; leaves linear-oblong, 

 irregular, 3-m any- toothed ; heads at length subglobose, about 1 cm. in diame- 

 ter, on slender terminal peduncles. — Brackish mud, P. E. I. (Churchill); on 

 ballast about Chelsea, Mass. ; also on the Pacific coast. (Adv. from s. Afr.) 



73. ARTEMISIA L. Wormwood 



Heads discoid, few-many-flowered ; flowers all tubular, the marginal ones 

 pistillate, or sometimes all similar and perfect. Involucre imbricated, dry and 

 scarious. Receptacle small and flattish. naked. Achenes obovoid, with a small 

 summit and no pappus. — Herbs or shrubby plants, bitter and aromatic, with 

 small commonly nodding heads in panicled spikes or racemes; flowering in 

 summer. Corolla yellow or purplish. (Ancient name of the Mugwort, in 

 memory of Artemisia, wife of Mausolus.) 



§ 1. Beceptacle smooth; marginal flowers pistillate and fertile; disk-flowers 

 perfect hut sterile, the style mostly entire; root perennial, except in no. 1. 



* Leaves dissected. 



1. A. caudata Michx. Glabrous or silky, 0.5-1.5 m. high ; upper leaves pin- 

 nately, the lower 2-3-pinnateiy divided ; the divisions thread-form, diverging ; 

 heads small (2-3 mm. broad); the racemes in a wand-like elongated panicle; 

 root biennial. — Sandy soil, Atlantic coast; also Vt. to Man., westw. and 

 southwestw. 



2. A. canadensis Michx. Smooth, or hoary with silky down, 3-6 dm. high •, 

 loioer leaves bipinnately divided, the upper 2'-! -divided ; divisions linear, rather 

 rigid; heads rather large (4-6 mm. broad), in panicled racemes: involucre 



