COMPOSIT;(E. 123 



11. A. tardiflo'rUS, L. Bays pale violet. Stem glabrous 

 or nearly so, 1-2 feet high. Leaves lanceolate or oblong- 

 lanceolate, acuminate, with tapering and somewhat aurioled 

 base. Heads few, as a rule. Involucre loose, the outer 

 scales leaf-like. — Atl. Prov. 



***Noneoftheleave8lieart-skaped; those of the stem sessile, tapering 

 at the base (except in No. 11). 



12. A. rad'ula, Ait. Bays light violet. Radical leaves 

 all tapering into margined petioles. Stem-leaves sessile, 

 oblong-lanceolate, pointed, sharply serrate in the middle, 

 very rough both sides, rugose. Scales of the bell-shaped 

 involucra oblong, appressed, with slightly spreading herb- 

 aceous tips. — Low grounds, Atl. Prov. 



13. A. erieoi'des. Ait. Bays white or nearly so. Stem 

 smooth or nearly so, 1-3 feet high, the branchlets or ped- 

 uncles racemose on the upper side of the spreading branches. 

 Lowest leaves oblong-spathulate, the others linear-lance- 

 olate or linear-awl-shaped. — Barren soil, and margins of 

 lakes and rivers. Var. villOSUS, Torr. and Gray, has hairy 

 stems and leaves. 



14. A. multiflo'rus. Ait. Bays white, 10-20. Stem pale 

 or hoary with minute pubescence, 1 foot high, bushy. 

 Leaves crowded, linear, with rough margins ; the upper 

 partly clasping. Heads small, crowded on the racemose 

 branches. Scales of the involucre with spreading green 

 tips. — Dry soil. 



15. A. Tradescan'ti, L. (A. tenuifoUus.) Bays white or 

 purplish. Scales of the involucre narrowly linear, in 3 or 4 

 rows. Heads small, very numerous, in 1-sided close racemes 

 on the branches. Stem 2-4 feet high, much branched, 

 smooth. Leaves linear-lanceolate, with long slender point, 

 the larger ones with a, few reTnote teeth in the middle. — Low 

 grounds. 



16. A. dlffu'SUS, Ait. (A. miser, L.) Bays pale blue or 

 whitish. Involucre nearly as in No. 15. Stem more or less 

 pubescentv much branched. Heads small, in loose 1-sided 



