324 
SYNGENESIA SUPERFLUA. 
1. Pycnostachyum. 
P. caule alato; foliis 
lanceolatis, sub undula- 
tis, denticulatis, subtus 
albo-tomentosis; spica 
cylindrica, densiflora. 
Mich. 
Stem winged; leaves 
lanceolate, slightly un- 
dulate, toothed, tomen- 
tose and white under- 
neath; spike cylindri- 
cal, flowers clustered. 
Conyza Pycnostachya. Mich. 2. p. 126. Pursh, 2. p. 524. Nutt. 2. p. 145. 
Gnaphalium Undulatum. Walt. p. 203. 
Root tuberous, somewhat fusiform, perennial. Stem about two feet high ? 
erect, simple, and with the under side of the leaves, and calyx densely to- 
mentose and white. Leaves sessile, lanceolate, widely decurrent, so as to 
render the stem conspicuously winged. Flowers in a compact sometimes 
compound spike ; female and hermaphrodite flowers promiscuously mingled 
in each capitulum, all white. Involucrum imbricate, leaflets somewhat obo» 
vate, acute, appearing to be scarious on the inner surface, densely tomentose 
without; female florets slender, three-cleft ; stamens none; style longer than 
the corolla, two-cleft, stigmas acute ; hermaphrodite florets with the corolla 
deeply five-cleft ; anthers very short ; style shorter than the corolla, two- 
cleft ; stigmas glandular, white. Seed angled, pubescent. Receptacle nakedj 
flat. 
This plant, as remarked by Michaux, should form an intermediate genus 
between Conyza and Gnaphalium, but it is in habit and appearance, much 
more nearly allied to the latter than the former ; many species in the last 
section of Conyza in Wildenow, perhaps belong to this genus. The seeds 
of the hermaphrodite florets are probably sterile. They are certainly much 
shorter than the others. The root under the popular denomination of Black 
Root is much used in some parts of the country as an alterative and as a 
deanser of old ulcers. 
Grows in dry sandy soils. 
Flowers May — August. 
GNAPHALIUM. Gen. Pe. 1282. 
Involucrum imbrica- 
tum, squamis oblongis, 
scariosis,coloratis. Co- 
rollulce foem. et herm. 
immixtae. Semina gla- 
bra. Pappus pilosus. 
Receptaculum nudum. 
Involucrum imbri- 
cate, scales oblong, 
scarious, coloured. Flo- 
rets fern, and herm. in- 
termingled. Sieds gla- 
brous. Pappus hairy. 
Receptacle naked. 
