468 
SYNGENESIA NECESSARIA. 
but the leaves of the former are ovate, while in the latter they are narrow' 
lanceolate, more pubescent underneath, and the corymb more diffuse. 
Grows in the mountainous districts of Carolina and Georgia. 
Flowers August — October. 
12. Atropurpureum. 
S. caule tereti, laevi; 
foliis subquaterno-ver- 
ticillatis, lanceolatis, 
scabris, subintegerri- 
mis, subsessilibus, basi 
ciliatis, superioribus 
sparsis; panicula dicho- 
toma. 
Retz. 
Stem terete, smooth; 
leaves verticillate by 
fours, lanceolate, sca- 
brous, nearly entire 
and sessile, ciliate at 
base, the upper ones 
scattered; panicle di- 
chotomous. 
Sp. pi. 3. p. 2334. Pursh, 2. p. 579- 
Stern about four feet high, dark purple, somewhat densely clothed with 
leaves; the lowest leaves alternate, the next ternate, then quaternate or 
rather in approximating pairs; the uppermost scattered, all lanceolate, den- 
ticulate, scabrous, with the midrib dark purple, on short fringed petioles. 
Florets of the ray very narrow. 
This species I have not seen; it is considered by Mr. Nuttall as a variety 
of the preceding. 
Grows in Carolina and Georgia, Pursh. 
Flowers August — September. 
13. Dentatum. E. 
S. caule erectum, 
subglabro; foliis inferi- 
oribus oppositis, supe- 
rioribus alternis, omni- 
bus lanceolatis, sinua- 
to-dentatis, pilosis, sca- 
bris; floribus corymbo- 
sis; involucri squamis 
lato-ovatis, ciliatis. 
Stem erect, some- 
what glabrous; lower 
leaves opposite, the 
upper alternate, all 
lanceolate, sinuate, 
toothed, hairy, sca- 
brous; flowers in co- 
rymbs; scales of the 
involucrum broad, o- 
vate, oiJiate. 
