Genus 31.] 



THISTLE FAMILY. 



363 



18. Aster cordifolius L. Common 

 Blue Wood Aster. (Fig. 3752.) ' 



As/er cordifolius L. Sp. PI. 875. 1753. 



Stem glabrous or nearly so, much 

 branched, bush^-, i°-$° high. Leaves 

 thin, rough, more or less pubescent with 

 scattered hairs above and on the veins 

 beneath, sharply serrate, acuminate, the 

 lower and basal ones slender-petioled, 

 broadly ovate-cordate, 2'-$' long, the 

 upper short-petioled or sessile, ovate or 

 lanceolate, smaller; petioles scarcely mar- 

 gined; heads very numerous, small, 2"-^" 

 high, i)"-9" broad, handsome; involucre 

 turbinate to cylindric, its bracts oblong- 

 linear, obtuse or obtusish, green-tipped, 

 appressed; rays 10-20, 3"-4" long, violet 

 or blue, sometimes pale (rarely white); 

 pappus whitish. 



Woods and thickets. New Brunswick to 

 Minnesota. Georgia and Missouri. Sept.- 

 Dec. 



Aster cordifolius Furbishiae Kernald. Proc. Portland Soc. Nat. Hist. 2: 129. 1897. 



Similar; stem and petioles densely villous, the leaves somewhat so beneath. Northern Maine. 

 Aster cordifolius polycephalus Porter, Bull. Torr. Club, 21: 120. 1804. 



Jlore robust and more branched than the type; leaves smaller, often rough only when dry, the 

 upper ones sessile, ovate; panicle large; heads usually smaller, very numerous; rays deep blue, or 

 paler. Massachusetts and eastern Pennsylvania to Virginia, 



Aster cordifolius alvearius Burgess. 



Leaves thin, usually smoothish. cordate, triangular-lanceolate, or broader; inflorescence dense, 

 thyrsoid. not leafy, in form resembling that of the lilac; bracts linear, acute; heads medium sized; 

 rays blue. On shaded banks, Massachusetts to North Carolina and Tennessee. 



Aster cordifolius pedicellatus Burgess. 



Stem leafy, often 4° high; leaves thin, the lower ovate, cordate, the upper ovate-lanceolate, or 

 those of the branches elliptic and subentire; inflorescence loosely pyramidal, often 2° high and \M° 

 broad, its ultimate branchlets long and often naked; heads large, 9" broad, or more, often 5" high; 

 rays chiefly purple-blue; bracts obtuse. In moist wood borders, Ontario to Virginia and Kentucky. 



19. Aster Lowrieanus Porter. 

 Lowrie's Aster. (Fig. 3753.) 



Aster cordifolius var. laei'igaltis Porter, Bull. 

 Torr. Club, lO: 67, 1889, Nol A. laevigatus 

 Lam, 1783, 

 As/er Lowrieanus Porter, Bull. Torr. Club, 21: 

 121. 1894. 



Glabrous, or very nearly so throughout; 

 stem branched, i°-4° high. Leaves thickish, 

 firm, a little succulent, the basal slender-peti- 

 oled, ovate to ovate-lanceolate, cordate, acute 

 or obtusish, serrate, 2'-6' long, those of the 

 stem ovate to oblong, often cordate, con- 

 tracted into winged petioles, the uppermost 

 lanceolate; heads usually not very numer- 

 ous, 2}i"-2," high, loosely panicled; involu- 

 cre turbinate, its bracts obtuse or obtusish, 

 appressed; rays light blue, 3"-4" long, but 

 variable in length. 



In woods, Connecticut and southern New 

 York to Pennsylvania, Ohio, Virginia and Ken- 

 tucky. Sept.-Oct. 

 Aster Lowrieanus lancifolius Porter. Mem. Torr. Club, $: 325. 1894. 

 A. cordifolius var. lanceola/tis Porter. Bull. Torr. Club,i6:68. 1889. Not^. lanceola/usWind. 1804. 

 Leaves lanceolate, appressed-serrate, only the basal ones cordate. Southern New York and 

 Pennsylvania. 



Aster Lowrieanus Bicknellii Porter, Mem, Torr, Club, 5: 325, 1894. 

 As/er cordifolius var. iiicisiis TirMon, Bull, Torr. Club, 19: 224, 1892, Not A.tuciSus Fisch. 1812. 

 Leaves all lanceolate, all sharply serrate, or the lowest incised, usually none of them cordate. 

 Southern New York and Pennsylvania. 



