196 COMPOSITE. (COMPOSITE FAMILY.) 



******* Leave,', entire, those of the stem sessile, the base ificn clasping: head* 

 solitary terminating the branches or somewhat corymbcd, large or middle-sized, showy ; 

 scales of the involucre very numerous, with loose and spreading or recurved mostly 

 fdiatxous tips, usually more or less glandular or viscid, as are the branchlets, Sfc. 

 *- Involucre imbricated, the scales in several or many ranks. 



29. A. grailtliflorus, L. Rough with minute hispid hairs ; stems slender, 

 loosely much-branched (l-3 high); leaves very small (' -1' long), oblong- 

 linear, obtuse, rigid ; the uppermost passing into scales of the hemispherical 

 Bquarrose many-ranked involucre; rays bright violet (!' long) ; achem'a hairy. 

 Dry open places, Virginia and southward. Heads large and very showy. 



30. A. Obloaigifolilis, Nutt. Minutely glandular-puberulent, much 

 branched above, rigid, paniculate-corymbose (1- 2 high) ; leaves narrowly ob- 

 long or lanceolate, mucronate-poimed, partly clasping, thickish (l'-2'long by 

 2" -5" wide); scales of the involucre broadly linear, appressed at the base, 

 ra/s violet-purple; achcnia canescent. Banks of rivers, from Penn. (Hunting- 

 do a County, Porter!} and Virginia to Wisconsin and Kentucky. Flowers not 

 half as large as those of the next. 



A. ABIETIIYSTINUS, Nutt., of Eastern Massachusetts, is a still wholly obscure 

 species. 



- - Involucre of many very slender equal scales appearing like a single row. 



31. A. Novro-AngliC, L. Stem stout, hairy (3 -8 high), corymbeu 

 at the summit ; leaves very numerous, lanceolate, entire, acute, auriculaterdasping, 

 clothed with minute pubescence: scales of the involucre linear-aui-shapcd, loose, glan- 

 dular-viscid, as well as the branchlets ; rays violet-purple, sometimes rose-purple 

 (A. roseus, Desf.), very numerous; achcnia hairy. Moist grounds ; common. 

 Heads large, corymbed. 



******** Head and imbricated involucre with leafy tips as in the preceding 

 group ; but the foliage as in * * *. 



32. A. mioimiliis, Engelm. Somewhat hoary-pubescent ; stems slendei 

 (oo -40 high), simple or racemose-branched above; leaves ovate or ovate-lance- 

 olate, pointed, entire or nearly so, the lower cordate and long-petiolcd, the upper 

 small and almost sessile; scales of the hemispherical involucre imbricated in 

 several rows, oppressed, with linear spreading leafy tips; achenia smooth. 

 Limestone dill's, W. Illinois (and Missouri), Engdmann. Heads as large as 

 those of No. 30 : rays violet-purple. 



f 4. ORITR6PHIUM, Kunth. Scales of the involucre narrow, nearly equal and 

 almost in a single row, more or less herbaceous : pappus of soft and uniform capil- 

 lary bristles : inaxtlij loir perennials, bearing solitary or few hids. 



33. A. gramillifolillS, Pursh. Slightly pubescent, slender (6'-12' 

 high) ; leaves very numerous, narrowly linear; branches prolonged into slendei 

 naked peduncles, bearing solitary small heads; rays rose-purple or whitish. 

 New Hampshire, about the White Mountains (Mr. Eddy in herb. Titckerman'i 

 L. Superior, and northward. 



$ 5. ORTH6MEKIS, TOIT. & Gr. Scales of the incohcre regularly imbricated, 

 unequal, often carinate, with membra naccvus margins, entirily destitute oj herbaceous 

 tips ' pappu* -)f soft and \\nequal capillary bristles. 



