COMPOSITE. 219 XANTHinM. 



Lat. lappa, a burr, from Gr. Xa-,3fn', to lay hold of ; a term well character- 

 izing' the burdock. Coarse European herbs. Root biennial. Leaves alter- 

 nate, large. 



L. MAJOR. Gaert. Arctium Lappa. L. 



Leaves cordate, unarmed, petioled. Common in waste and cultivated 

 grounds, fields. &c. Every one must necessarily be acquainted with the 

 burdock. Each plant is a large, conical, ill-scented and coarse looking mass 

 of vegetation, surmounted by a branching, irregular panicle of ovate beads 

 with tubular corollas of an e,\ceedino-ly delicate pink color. The leaves are 

 very large with wavy edges. This plant is an instance of design in the 

 disseminating of seeds, such as cannot be mistaken. The scales of the 

 involucre all end in a minute, firm hook, which seizes hold of every thing 

 that passes by. Thus men and animals are made the unwilling agents of 

 scatterinrr vvidely the seeds of this unsightly plant. July. Aug. Burdock. 



54. IVA. 

 Heads discoid; involucre 3-Ieaved ; marginal flowers 5, 

 fertile, the others sterile ; receptacle, hairy ; achenia obconic, 

 obtuse ; pappus 0. 



A name of barbarous origin. Herbs or shrubs. Lower leaves opposite. 



I. frute'scens. 



Leaves lanceolate, punctate, deeply serrate, rough ; stem shrubby. In the 

 borders of salt marshes. Stem thick, 3 — 8 feet high, with numerous oppo- 

 site branches. Leaves numerous, 3-nerved, upper ones entire. P^lowers 

 green, small, drooping, in close, leafy clusters. Aug. Per. High-water Shrub. 



55. XA'NTHIUM. 

 Heads heterocephalous. Slerile. — Involucre innbricate; 

 anthers approxinnate, but distinct ; receptacle chaffy. Fer- 

 tile. — Involucre 2-leaved, clothed with hooked prickles, 1 or 2 

 beaked, 2-flowered; stamens 0. 



Gr.^civdoi, yellow; a color which Dioscorides asserted to be communicated 

 to the liair by an infusion of these plants. Coarse, annual weeds, with alter- 

 nate leaves. 



1. X. Strum a'rium. 



Stem unarmed, branching; leaves cordate, lobed, 3-nerved, unequally 

 serrate, rough; fruit elliptical, armed with uncinate, stiff thorns, and ending 

 with 2, spreadmg, straight horns. A coarse, rough plant, in old fields, &c. 

 Stem branched, bristly, spotted, 2 — 3 feet hiu-h. Leaves large, on long stalks, 

 rigid. Sterile flowers few together, terminal, globular, green. Fertile in 

 sessile, axillary tufts. Fruit a hard, 2-celled burr, near an inch long, covered 

 with stiff, hooked prickles, which, like those of the common burdock, serve 

 to disperse the seeds. Aug. Ann. Clot-weed. 



2. X. ECHINA'tUM. Murray. X. macrocarpon. Dc. 

 Stem, rough and strigose, spotted ; leaves scabrous, obscurely lobed, obtuse, 



broad and subcordate at base, repand-toothed ; fruit ov&\, densely armed with 

 rigid, uncinate bristles; horns incurved. A very coarse plant in marshes 

 near the seacoast. Stem thick 1 — 2 feet high. Fruit very large, hairy. 

 Aug. — Oct. , 



