195 
of the branches elliptical to oblong-lanceolate, 6 to 12 mm. long; uppermost and the 
large ovate or ovate-lanceolate foliaceous portion of the involucral bracts cuspidate- 
acuminate, glabrate, conspicuously hirsute.—Prairies of western Louisiana and 
Texas. 
** * Leaves entire, the lower not heart-shaped, the cauline all with sessile and cordate- 
clasping base, the auricles generally meeting around the stem. 
7. A. patens Ait. Rough-pubescent: stem loosely panicled above, 3 to9 dm, 
high, with widely spreading branches, the heads mostly solitary, terminating slen- 
der branchlets: leaves oblong-lanceolate or ovate-oblong, often contracted below 
the middle, rough, especially above and on the margins: heads 12 niin. broad, 
with showy deep blue-purple rays: bracts of the minutely roughish involuere with 
spreading pointed tips: achenes silky.—Dry ground, extending from the Atlantic 
States into Texas at least as far west as Gillespie County. A common Texas form is 
var, GRACILIS Hook., which is lower and more slender, and with heads and oblong 
to oval leaves smaller and more scabrous. 
*** * Lower leaves heart-shaped and petioled : no glandular or viscid pubescence : heads with 
short and appressed green-tipped bracts, mostly n umerous, racemose or panicled, 
8. A. azureus Lindl. Stem rather rough, erect, racemose-compound at summit, 
the branches slender and rigid: leaves rough, entire or slightly serrate; the lower 
ovate Janceolate or oblong, heart-shaped, on long often hairy petioles; the others 
lanceolate or linear, sessile, on the branches awl-shaped: heads middle-sized : involu- 
cre inversely conical: rays bright blue.—Prairies and border of woods, extending 
from the Atlantic States into Texas, where there are forms with hardly a cordate 
leaf. 
9. A. Drummondii Lind]. Pale with fine gray pubescence: leaves conspicuously 
serrate, cordate to cordate-lanceolate, mostly on margined petioles, the uppermost 
lanceolate and sessile: heads small: involucral bracts acute or acutish: rays pale 
blue or nearly white.—Open grounds and borders of woods, extending from the Mis- 
sissippi States to western Texas. 
xe = * * Without heart-shaped petioled leaves, the radical and lower all acute or alternate 
at base: not glandular, or viscid, or silky-canescent, 
+ Smooth and glabrous throughout (or nearly so), and usually pale and glaucous : involu- 
cral bracts closely imbricated, firm and whitish-coriaceous below, green-tipped : leaves 
Jirm, usually entire. 
10. A. levis L. Rather stout, 6 to 12dm. high: leaves thickish, lanceolate or 
ovate-lanceolate, chiefly entire, the upper more or less clasping by an auricled or 
heart-shaped base, those on the branchlets reduced to rigid subulate bracts: heads in 
a close panicle: bracts of the short-oboyoid or hemispherical involucre with short 
abrupt green tips: rays sky-blue.—Borders of woodlands throughout Texas, 
11. A. virgatus Ell. Slender, strict and simple, with few or several racemose or 
terminal heads like those of the last: leaves lanceolate or linear, the lower usually 
long and narrow, the uppermost reduced to rigid subulate bracts.—Extending from 
the Gulf States into Texas. 
++ Hoary-pubescent or hirsute: herbaceous tips of the involucral bracts squarrose or 
spreading : cauline leaves small, linear, entire, scarcely narrowed at the sessile or 
partly clasping base: heads numerous, small, racemose. 
12. A. multiflorus Ait. Pale or hoary with minute close pubescence, 3 dm. high, 
much branched and bushy: the heads much crowded _on the spreading racemose 
branches: leaves rigid, crowded, spreading, with rough of ciliate margins, the upper- 
most passing into the spatulate obtuse bracts: heads 4 to 6 mm. long: rays white or 
rarely bluish, 10 to 20.—Dry or sterile ground, common throughout Texas. 
+++ Bracts glabrous, closely imbricated (the outer regularly shorter), not coriaceous, with 
short appressed green tips: branches slender, divaricate or divergent: leaves 
lanceolate to subulate: heads small, 4 to 6mm, high, numerous. 
18430—No, 2——4 
