692 COMPOSITAE 
deeply lobed. Heads small in somewhat diffuse elongated clusters. Waste 
places, introduced. July-Oct. 
Plants not woolly 
8. A. biennis, L. (Fig. 5, pl. 194.) BrennrAt Wormwoop. Smooth, 
branching, 1 to 4 ft. high. Leaves doubly feather-formed. Heads numer- 
ous, in the leaf-axils. Introduced from the Northwest Territory, in Penna., 
and westward. Aug.-Oct. 
43. TUSSILAGO, L. 
A low herb with perennial root-stock from which, in very early spring, 
March or April, a scape arises bearing at its summit a flower head in- 
cluding both ray and tubular florets, the stem bearing also alternate 
scales. Later, broad rounded heart-shaped, angular and toothed leaves 
which, when young are woolly, appear and replace the flower stem. 
T. Farfara, L. (Fig. 1, pl. 195.) Cotrsroor., Scape 4 to 6 in. high, 
flowers yellow. Grows in wet places, often on banks of streams. The 
flower and leaves are not generally seen together as the flowers are 
withered when the leaves appear. 
44. PETASITES, Gaertn. 
Herb from perennial rootstock resembling Tussilago, but heads are in 
a cluster. Scape bearing scales; leaves deeply lobed. Rays white or 
purple. 
1. P. palmata, (Ait.) A. Gray. (Fig. 2, pl. 195.) PALMATE-LEAVED 
SweEer CoLtrsroot. Scape 6 to 24 in. high. Leaves densely white-silky. 
Flowers nearly white. 
2. P. vulgaris, Hill. (Fig. 3, pl. 195.) ButTrer-sur. Scape very 
stout, the bracts large. Leaves rounded, heart-shaped, with irregular, 
regular and toothed borders. Flower-heads.in a dense cluster, purplish. 
In parks and, in a few localities, in waste grounds. Naturalized, from 
Europe. April-May. 
45. ARNICA, L. 
Erect, stem simple or slightly branched; leaves opposite. Heads or 
long stems; rays yellow; involucre bracts of equal lance-shaped scales in 
1 or 2 series; receptacle flat, naked or with a few scattered hairs. Fruit 
linear, 5- to 10-ribbed. Aigrette of a single series of rigid but rough 
bristles. 
1. A. mollis, Hook. (Fig. 4, pl. 195.) Cramisso’s Arnica. Stem 
downy with long hairs, simple, 1 to 23 ft. high. Leaves downy, becoming 
less so, 2 to 5 in. long, the upper without leaf-stalks. Heads 1 to 6 at 
the summit of the stem; involucre hairy; rays 10 to 15, yellow, 3-toothed. 
High places on the Adirondack and White Mountains. June-Aug. 
2. A. acaulis, (Walt.) BSP. (Fig. 5, pl. 195.) LropaRp’s-BANE. 
Stem hairy with few (1 to 3 pairs) of leaves, 1 to 3 ft. high. At summit 
several heads on rather long flower-stems. Basal leaves in a tuft or 
rosette, egg-shaped or oval, hairy, with about 5 longitudinal nerves, 
Delaware and Southern Penna. April-May. 
