264 COMPOSITE. (COMPOSITE FAMILY.) 



49. A. ptarmicoides, Torr. & Gray. Smooth or roughish ; stems clus- 

 tered (6 - 20' high), simple ; leaves linear-lanceolate, acute, rigid, entire, tapering 

 to the base, 1 -3-nerved, with rough margins (2-4' long) ; heads small, in a 

 flat corymb; scales imbricated in 3 or 4 rows, short; rays white (2-4" long). 

 Dry rocks, W. New Eng. to Minn., along the Great Lakes, and northward. 

 Aug. Var. LUTESCENS, Gray; rays small, pale yellow. N. 111. and Sask. 



50. A. acuminatUS, Michx. Somewhat hairy; stem (about 1 high) 

 simple, zigzag, panicled-corymbose at the summit ; peduncles slender ; leaves 

 oblong-lanceolate, conspicuously pointed, coarsely toothed above, wedge-form and 

 entire at the base ; involucral scales few and loosely imbricated, linear-lanceo- 

 late, pointed, thin (3-5" long); heads few or several; rays 12-18, white, or 

 slightly purple. Cool rich woods; S. Lab. to Penn., and southward along 

 the Alleghanies. Aug. There is a depauperate narrow-leaved variety on 

 the White Mountains. A monstrous form occurs in Maine, having a chaffy 

 receptacle and the flowers turned to tufts of chaffy paleae. 



51. A. nemoralis, Ait. Minutely roughish-pubescent ; stem slender, 

 simple or corymbose at the summit, very leafy (1-2 high) ; leaves small (1 - 

 1^' long), rather rigid, lanceolate, nearly entire, with revolute margins ; scales of 

 the inversely conical involucre narrowly linear-lanceolate, the outer passing 

 into awl-shaped bracts ; rays lilac-purple, elongated. Bogs and swamps, N. J. 

 to Newf. and Hudson's Bay. Sept. 



52. A. tenuifblius, L. Very glabrous; stem often zigzag, simple or 

 forked, 6' -2 high; heads rather large, terminal ; leaves few, long-linear, ta- 

 pering to both ends, rather thick and fleshy, entire, the upper subulate, pointed; 

 involucre top-shaped, the scales subulate-lanceolate with attenuate acute points ; 

 rays large, numerous, pale purple. (A. flexuosus, Nutt.) Salt marshes, 

 Mass, to Fla. Sept. 



7. OXYTRIP6LIUM. Involucre as in 6; pappus simple, fine and soft; 

 glabrous annuals, bearing numerous small heads and with narrow entire leaves. 



53. A. SUbulatUS, Michx. Stem 6 - 24' high ; leaves linear-lanceolate, 

 pointed, flat, on the branches awl-shaped ; scales of the oblong involucre linear- 

 awl-shaped, in few rows ; rays somewhat in two rows, short, not projecting be- 

 yond the disk, more numerous than the disk-flowers, purplish. (A. linifolius. 

 of previous ed.) Salt marshes on the coast, Maine to Va. Aug. - Oct. 



8. CONYZ6PSIS. Scales of the campanulate involucre in 2 or 3 rows, nearly 

 equal, linear, the outer foliaceous and loose ; pappus copious, very soft ; rays 

 very short or without ligules / low annuals with numerous rather small heads. 



54. A. anglistus, Torr. & Gray. Branching, 6-20' high, nearly gla- 

 brous ; leaves linear, entire, more or less short-ciliate ; ray-flowers reduced to a 

 tube much shorter than the elongated style. Minn, to Sask. and westward, 

 spreading east to Chicago, etc. (Siberia.) 



26. ERIGERON, L. FLEABANE. 



Heads many-flowered, radiate, mostly flat or hemispherical; the narrow 

 rays very numerous, pistillate. Involucral scales narrow, equal and little im- 

 bricated, never coriaceous, foliaceous, nor green-tipped. Receptacle flat or 

 convex, naked. Achenes flattened, usually pubescent and 2-nerved ; pappus a 



