808 



COMPOSITAE (composite FAMILY) 



937. A. azureus. 



938. A. Shortii. 



leaves rough, the loicer ovate-lanceolate or oblong, heart-shaped, on long often 

 haii'y petioles; the others lanceolate or linear, sessile, on the branches awl- 

 shaped ; involucre inversely conical. — Copses and prairies, 

 w. N. Y. and Ont. to Minn., Mo., and southw, Sept., Oct. 

 — Involucre much as in A. laevis, but smaller and slightly 

 pubescent. Fig. 937. 



21. A. Sh6rtii Lindl. Stem slender, spreading, nearly 

 smooth, bearing very numerous heads in racemose panicles ; 

 leaves smooth above, minutely pubescent 

 underneath, lanceolate or ovate-lanceolate, 

 elongated, tapering gradually to a sharp 

 point, all but the uppermost more or less 

 heart-shaped at base and on naked petioles, 

 none clasping ; involucre bell-shaped. — 

 Cliffs and banks, w. Pa. to 111., and southw. 

 Aug. -Oct. — A pretty species, 1 m. high; 

 leaves 0.5-1.5 dm. long. Fig. 938. 



22. A. undulatus L. Pale or somewhat hoary with close 

 pubescence ; stem spreading, bearing numerous heads in race- 

 mose panicles ; leaves ovate or ovate- 

 lanceolate, imth wavy or slightly toothed 

 margins, roughish abcjve, doiony under- 

 neath; the lowest heart-shaped, on margined petioles ; the 

 others abruptly contracted into short broadly winged peti- 

 oles which are dilated and clasping at the base, or directly 

 sessile by a heart-shaped base ; involucre olbovoid, the 

 bracts less rigid. — Dry copses, N. B. to Ont., Minn., and 

 southw. Aug.-Nov. Fig. 939. — Very variable in outline 

 of leaves, etc. , upon which characters Professor E. S. Bur- 

 gess proposes many species. 



*+ ++ Leaves for the most part conspicuously serrate; rays 

 pale blue or nearly white. 



23. A. cordifolius L. Stem nearly glabrous, much 

 branched above, the spreading or diverging branches bearing 

 very numerous panic! ed. heads; leaves thin, sharply serrate, 

 minutely scabrous above; the loiver all heart-shaped, on 



generally slender and naked ciliate peti- 

 oles ; the upper chiefly cordate ; bracts 

 of the inversely conical involucre all 

 appressed and tipped icith very short green 

 points, obtuse or acutish. — Woods and 

 thickets, e. Que. to la., s. to Ga. and Mo. 

 Aug. -Oct. — Heads profuse, but rather 

 small. Fig. 940. Var. Furhishiae Fer- 

 nald. Stems, petioles, and lower surfaces 

 of leaves densely villous. — Banks of 

 streams, N. B., Me., and N. H. Var. polycephalus Porter. 

 Most of the upper leaves truncate or narrowed at base. — 

 Range of the typical fonn. 



24. A. Lowrieanus Porter. Kcsembling A. crtrdifolins ; 

 leaves thickish, glaucous beneath, smooth, often grea.sy to the 

 touch, sharply or obscurely serrate ; the Irncer ovate, cordate, 

 on mostly winged petioles. — Open woods and thickets, Ct. to 

 Ont. and N. C. Sept., Oct. Var. lanckolXti s Porter. Most 

 of the lower leaves lanceolate or lance-ovate, truncate or nar- 

 rowed at base. (Ya,Y.lancifolius Porter.) — Similar range. Var. incisus Porter. 

 Leaves all lanceolate, the lower incised. (Var. Bicknellii Porter.) — N. Y. and 

 Pa., local. 



25. A. sagittifolius Wedemeyer. Stem rigid, erect, smooth or slightly 



939. A. undulatus. 



940. A. cordifolius. 



sagittifolius. 



