232 COMl'OSlTvE. (cOJIPOSITIi FAMILY.) 



pointed at both ends ; scales of the oblong involucre linear, tapering into awl-shaped 



slender and loose tips. — Dry ground, New York and Penn. to Kentueky and 



nortlnvard. — Usually more or less hairy or downy ; the heads rather lar<,^er 



than in the last, almost sessile. — A. Drummondii, Lindl., whieh probal)ly 



grows on the Illinois side of the Mississippi, is a downy-leaved variety of this. 



* ♦ * ♦ Leaves none of them heart-shaped ; those of the stem sessile, narrow, rigid, 



entire: involucre imbricated in several rows: the coriaceous scales appressed and 



whitish lit the base, with abrupt and conspicuous spreading herlxjceous tips : heads 



stnall and i-enj numerous, paniculate-racemose ; rai/s white. 



17. A. erieoides, L. Smuothor sparingly hninj {\° -\^° Wv^hj ; tlie sim- 

 ple branchk'ts or peduueles racemose along the upper side of rlie wand-like 

 spreading branches; lowest leaves obloiig-spatulate, sometimes tootliL-d ; the ul hers 

 linear-lanctolate or linear-awl-shaped, acute at both ends ; scales of the involucre 

 broadest at the base, with acute or awl-sluipal green tips, — Var. vill6sus is a 

 luiiry form, often with broader leaves ; chiefly in the Western States. — Dry 

 open places, S. New England to Wisconsin and soiuliward. 



18. A. multiflbl'US, Ait. I'ale or koarg with minute close pubescence (1° 

 high), much branched and bushy ; the heads much crowded on the spreading 

 racemose branches ; leaves crowded, linear, spreading, with rough or ciliate mar- 

 gins, the upper somewhat dilated and purtlg clasping at the base ; scales of the in- 

 volucre with spalulatc spreading green tips broader than the lower portion, the outer 

 obtuse. — Dry gravelly or sandy soil : common. 



***** Leaves none of them lieart-shaped ; those of the stem tapering at the b'ise, 

 sessile ; involucre imbricated ; the scales tmequal, with short and narrow up- 

 pressed or rather loose greenish tips: lauds small or middU-sized : raijs ivhite or 

 bluish-purple. 



H- Heads stnall. (Involucre 2" -4" long.) 

 19- A. dum6sus, L. Smooth or nearly so, racemosely compound, the 

 scattered heads mostly solilarij at the end of the spreading branchlets ;. leaves linear 

 or the upper ol)long, crowded, entire or slightly serrate, with rough margins ; 

 scales of the closdg imbricated involucre linear-spatulate, obtuse, in 4 - 6 rows. — 

 Thickets: common. — Available species, 1°-. 3° high, loosely branched, with 

 small leaves, especially the upper, and an inversely conical or bell-shaped invo- 

 lucre, with more abrupt green tips than any of the succeeding. Rays pale 

 purple or bliu\ lar!_''er tlian in the next. Runs into several peculiar forms. 



20. A. Tradescanti, L. Smooth or smcothish : the nunvrons heads closely 

 racemed along one side of the erect-spreading or diverging branches ; leaves 

 lanceolate-linear, elongated, the larircr ones remotely serrate in the middle with 

 fine sh.'irp teeth ; scales of the inrohirrp narrowly linear, arute or acullsh, in .3 or 4 

 rows. — Var. frAoii.is has the leaves entire or nearly so, except the lowest, 

 the heads more scattered. — Moist banks : very common. — Stems 2° - 4° 

 high, bushy : heads very numerous, smaller than in the last. Rays white or 

 nearly so. 



21. A. miser, L., Ait. More or If ss hairy, much hTi\nchL'i\ ; the brunches 

 usually divcri^ing, bearing racemose often srallerrd heads; leaves lanceobite or ob- 

 long-lanceolate, tapering or pointed at each end, bharply serrate in the middle • 



