COMPOSITA. (COMPOSITE FAMILY.) 201 
lanceolate, acute, appressed. — Lincolnton, North Carolina, Curtis. — Stem pur- 
ple, 2°-3° high. Lower leaves 5/—6/ long, 3" wide. Heads smaller than those 
of the preceding. ; 
17. A. virgatus, Ell. Stem very smooth, straight, bearing the heads in 
a single raceme at the summit of the long and slender branches; leaves linear- 
lanceolate, entire, rough on the margins, partly clasping, the lowest broader and 
narrowed at the base; scales of the involucre lanceolate, acuminate; the outer 
ones spreading. — Western districts of Georgia, and westward. — Stem 39-49 
high. Lower leaves 3'—6/ long; those of the branches small and numerous. 
18. A. concinnus, Willd. Stem nearly smooth, somewhat loosely cor- 
ymbose; the branches virgate, dichotomous-paniculate ; leaves lanceolate, 
partly clasping, remotely and sharply serrate, with scabrous margins; those of 
the branchlets oblong, entire; scales of the involucre linear, acute, closely imbri- 
càted: (A. cyaneus? Ell.) — Fonds to North Carolina. — Stem 2°-3° high. 
Achenia pubescent. 
* * * * Lower leaves large, cordate, on long petioles: heads middle-sized or small, 
racemed or panicled: scales of the involucre somewhat membranaceous, with short 
green tips: rays blue or violet. 
+ Leaves entire, or nearly so. 
19. A. azureus, Lindl. Stem roughish, rigid, racemose-compound at the 
summit, the branches slender; leaves rigid, rough; the lowest ovate-lanceolate 
or oblong ; the upper lanceolate or linear, sessile; those of the branches subu- - 
late, appressed; scales of the obconical jival closely imbricated, abruptly 
acute. — Dry soil in the upper districts of Georgia and northward. — Stem 2°- 
3° high. Rays bright blue. 
20. A. Shortii, Hook. Stem smoothish, slender, racemose-panicled at the 
Summit; leaves nearly smooth, ovate-lanceolate, acute; those of the stem all on 
slender petioles, and obtuse or cordate at the base, commonly entire; those of 
the branches oblong, sessile; scales of the bell-shaped involucre linear, closely 
imbricated, rather obtuse, enter than the disk. — Mountains of Georgia and 
Westward. — Stem 29 —49 high. Rays violet-blue. 
?l. A. undulatus, L. Pubescent; stem racemose-panicled above; leaves 
varying from lanceolate to broadly ovate, often wavy or slightly serrate on the - 
margins, roughish on the upper surface; the lowest on long and slender petioles, - 
are dilated and clasping at the base; the upper on broadly winged peti- 
oles, or sessile and clasping ; scales of the obovoid involucre linear, appressed, 
acute. (A. diversifolius, A. sagittifolius, and A. scaber, Ell.; the last with 
smaller leaves, and very rough on both sides.) — Woods, common and very va- 
= Aud 29-39 high. Heads small. Rays Ls blue. 
A or simple; lowest leaves oblong-ovate, obtuse 2e Maid coniete at ded "m 
UM Rings Lario, vn. slendet-(uct clasping) petioles; the upper oblong, 
dinem menor on sbort vi eae those of the 
