40 
DESCRIPTION OF MEDICINAL PLANTS. 
with white rays and yellow disk. Involucre hemispherical, 
of small imbricated dry and scarious scales shorter than the 
disk ; receptacle without chaff near the margin. Pappus 
none. It is generally better known as dog fennel, and is 
an intrusive weed. Eli Lilly & Co. prepare a fluid extract 
from the herb. 
Achillea Millefolium, L. Yarrow or Milfoil. Perennial 
herb, with small corymbose heads. Stems simple ; leaves 
twice-pinnately parted ; the divisions linear, 3-5 cleft, 
crowded ; corymb compound, flat-topped ; involucre oblong ; 
rays 3-4 short, white. Achenes oblong, flattened, margined ; 
pappus none. Roadsides and dry pastures, adventitious but 
naturalized from Europe. It makes an esteemed veterinary 
medicine. The flowering plant. 
Chrysanthemum Leucanthemum, L. Ox-Eye Daisy. Peren- 
nial herb w ith single stem 1-1 high, naked above and bear- 
ing a single large head. Rootleaves spatulate, petioled, the 
others partly clasping, all cut or pinnatifid-toothed. Head 
IP wide, rays numerous, fertile. Scales of the broad and flat 
involucre imbricated with scarious margins. Receptacle 
flat or convex, naked. Disk-corollas with a flattened tube. 
Achenes of disk and ray similar, striate, without pappus. 
Native from Europe and largely spreading over the State. 
Eli Lilly & Co. use the flowering herb for a fluid extract. 
** FI. the whole summer. 
Tanacetum vulgare, L. Common Tansy. Bitter and acrid strong- 
scented perennial, with 1-3 pinnately dissected leaves and 
corymbed heads. Stem 2-4° high, smooth; leaflets and the 
wings of the petiole cut-toothed; corymb dense; pistillate 
flowers terete, with oblique 3-toothed limb, pappus 5-lobed. 
FI. summer. The leaves are collected in flowering season. 
Frequently cultivated in gardens and escaped into fence- 
rows. 
Artemisia Absinthium, L. Wormwood. An erect undershrub. 
Leaves silky, hoary, tripinnatisect ; the segments lanceolate, 
somewhat dentate, obtuse. Heads discoideal, homogamous 
