SYNGENESIA SUPERFLUA. 
401 
Sp. pi. 3. p. 2122. Pursh, 2. p. 526. Nutt. 2. p. 168 . 
Chrysanthemum serotinum. Walt. p. 206. 
Root perennial. Stem one to two feet high, sparingly branched, nearly 
glabrous. Leaves alternate, sessile, amplexicaule, glabrous, oblong, toothed 
or notched, towards the base nearly pinnatifid. Flowers solitary on the 
branches. Involucrum imbricate, leaves subulate, glabrous, with the mar* 
gins membranaceous. Florets of the ray about thirty, white, obscurely 
three-toothed at the summit; of the disk very numerous, yellow. Stamens 
short. Style longer than the stamens, two-cleft. Seeds furrowed. Recep - 
tacle naked. 
Grows in clay soils. An exotic now naturalized, particularly in the up- 
per country. 
Flowers May — July. 
HELENIUM. 
Involucrum simplex, 
multipartitum. Corol- 
lulce radii semitrifidae. 
Pappus paleaceus, pa- 
leis 5, aristatis. Re- 
ceptaculum globosum, 
nudum, radii paleace- 
um. 
Gen. Pl. 1299. 
Involucrum simple, 
many parted. Rays of 
the corolla deeply 3- 
cleft. Pappus chaffy, 
chaff 5 awned. Re- 
ceptacle globose, nak- 
ed, of the ray chaffy. 
1. Autumnale. 
Leaves lanceolate, 
serrate, decurrent; 
flowers in corymbs; 
florets of the disk 5- 
cleft; of the ray flat, 
reflexed. 
Sp. pi. 3. p. 1120. Mich. 2. p. 133. Pursh, 2. p. 560. Nutt. 2. p. 
173. 
Root perennial. Stem two to three feet high, branching towards the 
summit, glabrous and winged by the decurrent leaves. Leaves alternate, 
sessile, doubly serrate, glabrous. Flowers in small corymbs, the peduncles 
pubescent near the summit. Involucrum eight-parted, the segments subu- 
late, entire, twice as long as the disk. Florets of the ray about ten, obovate, 
VOL. IK E 3 
H* loins lanceolatis, 
serratis, decurrentibus; 
floribus corymbosis; 
corollulis disci 5-fidis; 
radii planis, reflexis. 
