An acaulescent herb, more or less white-tomentose, with slender perennial rootstocks, broad basal cordate, dentate or lobed, long-petioled leaves, and large solitary, monoecious heads of both tubular and radiate yellow flowers at the summit of a scaly scape, appearing before the leaves of the season. Involucre campanulate to cylindric, its principal bracts in a single series, equal, with or without a few shorter outer ones. Receptacle flat, naked. Ray-flowers in several series, pistillate, fertile. Disk-flowers perfect, sterile, the corolla 5-cleft,.the style undivided and obtuse, lobed. Achenes of the ray-flowers linear, 5-10-ribbed. Pappus copious, of numerous slender roughish bristles, that of the sterile flowers shorter than that of the fertile. [Latin, tussis, cough, for which the plant was a reputed remedy.]

A monotypic genus of northern Europe and Asia.

95 Tussilago Tourn L Sp Pl 865 1753 1265

1. Tussilago Farfara L. Coltsfoot. Coughwort

Fig. 4594

Tussilago Farfara L. Sp. Pl. 865. 1753.

Scape slender, 3'-18' high, bearing a solitary large head at the summit. Leaves nearly orbicular, or broadly ovate-reniform, angulately lobed and dentate, 3'-7' broad, green and glabrous above, persistently white-tomentose beneath; head about 1' broad; involucre campanulate; rays bright yellow, numerous, linear.

In moist soil, on banks and roadsides, Nova Scotia and New Brunswick to New Jersey, Pennsylvania and Minnesota. Naturalized from Europe. Horse-foot. Horse-hoof. Dove-dock. Sow-foot. Colt-herb. Hoofs. Cleats. Ass's-foot. Bull's-foot. Foal-foot. Ginger. Clay-weed. Butter-bur. Dummy-weed. April-June.