Genus 31.] 



THISTLE FAMILY. 



363 



18. Aster cordifdlius L,. Common 



Blue Wood Aster. (Fig. 3752.) ' 

 Aster cordifolius L. Sp. PI. 875. 1753. 



Stem glabrous or nearly so, much 

 branched, bushy, i-5 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 / -5 / long, the 

 upper short-petioled or sessile, ovate or 

 lanceolate, smaller; petioles scarcely mar- 

 gined; heads very numerous, small, 2 // ~3 // 

 high, 6 // -o/ / 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 Fernald, 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. 

 More 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, 

 thyreoid, 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 leaf y, 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 andij^ 



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.) 



Asler cordifolius var. laevigatus Porter, Bull. 



Torr. Club, 16:67. 1889. Not A. laevigatus 



Lam. 1783. 

 Aster 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^ // -3 // 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, 5: 325. 1894. 

 A. cordifolius var. lanceolatus Porter, Bull. Torr. Club,i6: 68. 1889. Not A. lanceolaiusWiUd. 1S04. 

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

 Pennsvlvania. 



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

 Asler cordifolius var. incisus Britton, Bull. Torr. Club, 19: 224. 1892. Not A. incisus Fisch. 1S12. 

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

 Southern New York and Pennsylvania. 



