Part 13 (2/2)

wide or less, the red beak 1 mm. long, p.r.i.c.kles often extending nearly to the base along twelve vertical ribs, the achenes narrower, shorter, much darker in color, with p.r.i.c.kles extending farther down the ribs, the short beak longer; the plant is earlier, often smaller, when compared with the other species.

Doubtless this is more common than has been reported, having been overlooked. Introduced from Europe.

[Ill.u.s.tration: Fig. 212.]

=Dandelion.= _Taraxac.u.m officinale_ Weber. _Taraxac.u.m Taraxac.u.m_ (L.) Karst. Flowers yellow; achenes dull light to dark brown, flattened oblanceolate, thread-like beak two to three times as long as the achene, the stout colored beak 0.5 mm. long. The most conspicuous character of the achenes lies in the barb-like-toothed edges and ridges of each of the similar faces, extending along the upper half. Achene, 3-4 mm. long, having twelve longitudinal ridges, 1.2 mm. wide. Introduced from Europe.

Troublesome on thin lawns.

[Ill.u.s.tration: Fig. 213.]

=Salsify. Oyster-Plant.= _Tragopogon porrifolius_ L. Flowers purple; achenes dull light brown, nearly cylindrical; apex tapering, mostly terminating in a slender beak which is often longer than the body of the achene. Achene straight or curved, 10-ribbed, 12-18 mm. long, outermost coa.r.s.ely roughened by upwardly directed, whitish, scale-like projections. Native of Europe.

=Meadow Salsify. Yellow Goat's Beard.= _Tragopogon pratensis_ L. Flowers yellow; achenes dull, light brown, nearly cylindrical, apex tapering, mostly terminating in a slender beak. Achene straight or curved, 10-ribbed, 12-15 mm. long, the inner ones of the head smooth, the outer-most coa.r.s.ely roughened by upwardly directed, whitish, scale-like projections. Introduced from Europe.

[Ill.u.s.tration: Fig. 214.]

=American c.o.c.klebur.= _Xanthium Canadensis_ Mill. Achenes or burs reddish brown, oblong, circular in section, two-beaked, about 20 mm.

long, covered with stout hooked p.r.i.c.kles. Each bur encloses two seeds.

Native of this country.

[Ill.u.s.tration: Fig. 215.]

=Spiny Clotbur.= _Xanthium spinosum_ L. Bur oblong, light brown, very slightly flattened, 10-13 mm. long, the beaks weak and small, small hooked p.r.i.c.kles 3-4 mm. long, each bur contains two seeds. Introduced from Europe.

=Broad c.o.c.klebur.= _Xanthium strumarium_ L. Bur dark brown, oval, circular in sections 12-22 mm. long, beaks stout, nearly straight, spines about 5 mm. long, surface of burs and base of spines clothed with minute hooked p.r.i.c.kles. Naturalized from Europe.

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