50. A. acuminàtus, 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-lanceolate, 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 paleæ.
51. A. nemoràlis, Ait. Minutely roughish-pubescent; stem slender, simple or corymbose at the summit, very leafy (1–2° high); leaves small (1–1½´ 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. tenuifòlius, L. Very glabrous; stem often zigzag, simple or forked, 6´–2° high; heads rather large, terminal; leaves few, long-linear, tapering 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. OXYTRIPÒLIUM. Involucre as in § 6; pappus simple, fine and soft; glabrous annuals, bearing numerous small heads and with narrow entire leaves.
53. A. subulàtus, 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 beyond 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. CONYZÓPSIS. 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. angústus, Torr. & Gray. Branching, 6–20´ high, nearly glabrous; 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. ERÍGERON, L. Fleabane.
Heads many-flowered, radiate, mostly flat or hemispherical; the narrow rays very numerous, pistillate. Involucral scales narrow, equal and little imbricated, never coriaceous, foliaceous, nor green-tipped. Receptacle flat or convex, naked. Achenes flattened, usually pubescent and 2-nerved; pappus a single row of capillary bristles, with minuter ones intermixed, or with a distinct short outer pappus of little bristles or chaffy scales.—Herbs, with entire or toothed and generally sessile leaves, and solitary or corymbed naked-pedunculate heads. Disk yellow; ray white or purple. (Name from ἦρ, spring, and γέρων, an old man, suggested by the hoariness of some vernal species.)
§ 1. CÆNÒTUS. Rays inconspicuous, in several rows, scarcely longer than the pappus; pappus simple; annuals.