848 coMPOSiTAE (composite family) 



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

 gardens. (Introd. from Asia.) 



71. TANACETUM L. Tanst 



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 corymbed (rarely single) heads. Flowers yellow, 

 in summer. (Name of uncertain derivation.) 



I. T. vulgXre L. (Common T.) Stem 0.5-1 ni.high, smooth; leaflets and 

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

 with oblique 3-toothed limb ; pappus 5-lobed. — Escaped from gardens to road- 

 sides, etc. (Introd. from Eu.) Var. CKfspoM DC. Leaves more cUt and crisped. 



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



2. T. huron^nse Nutt. Hairy or woolly 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 

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



72. c6TULA [Toum.] 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 raised 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 KoriX-q, a small cup, alluding to the hollow at the base of 

 the amplexicaul leaves. ) 



1. C. coKONOPir6LiA L. Branched from the base, decumbent and often 

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

 irregular, 3-many-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. Af r.) 



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 

 soarious. 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 but sterile, the style mostly entire; root perennial, except in no. 1. 



* Leaves dissected. 



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

 nately, the lower 2-3-pinnately 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 

 south west w. 



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

 loioer leaves bipinnately divided, the upper 3-1-divided ; divisions linear, rather 

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



