1. M. rèpens, L.—Dry woods, creeping about the foot of trees, especially Coniferæ, throughout our range and southward. June, July.—Leaves often variegated with whitish lines. Rarely the two flowers are completely confluent into one, with a 10-lobed corolla.

5. SPERMACÒCE, Dill. Button-weed.

Calyx-tube short; the limb parted into 4 teeth. Corolla funnel-form or salver-form, valvate in the bud. Stamens 4. Stigma or style 2-cleft. Fruit small and dry, 2-celled, 2-seeded, splitting when ripe into 2 carpels, one of them usually carrying with it the partition, and therefore closed, the other open on the inner face.—Small herbs, the bases of the leaves or petioles connected by a bristle-bearing stipular membrane. Flowers small, whitish, crowded into sessile axillary whorled clusters or heads. (Name compounded of σπέρμα, seed, and ακωκή, a point, probably from the pointed calyx-teeth on the fruit.)

1. S. glàbra, Michx. Glabrous perennial; stems spreading (9–20´ long); leaves oblong-lanceolate; heads many-flowered; corolla little exceeding the calyx, bearded in the throat, bearing the anthers at its base; filaments and style hardly any.—River-banks, S. Ohio to Ark., Tex., and Fla. Aug.

6. DIÒDIA, Gronov. Button-weed.

Calyx-teeth 2–5, often unequal. Fruit 2- (rarely 3-) celled; the crustaceous carpels into which it splits all closed and indehiscent. Flowers 1–3 in each axil. Otherwise resembling Spermacoce. Flowering all summer. (Name from δίοδος, a thoroughfare; the species often growing by the wayside.)

1. D. Virginiàna, L. Smooth or hairy perennial; stems spreading (1–2° long); leaves lanceolate or oblong-lanceolate, sessile; corolla white (½´ long), the slender tube abruptly expanded into the large limb; style 2-parted; fruit oblong, strongly furrowed, crowned mostly with 2 slender calyx-teeth.—Low grounds along streams, southern N. J. to Fla., west to Ark. and Tex.

2. D. tères, Walt. Hairy or minutely pubescent annual; stem spreading (3–9´ long), nearly terete; leaves linear-lanceolate, closely sessile, rigid; corolla funnel-form (2–3´´ long, whitish), with short lobes, not exceeding the long bristles of the stipules; style undivided; fruit obovate-turbinate, not furrowed, crowned with 4 short calyx-teeth.—Sandy soil, N. J. to W. Ill., Fla., and Tex.

7. GÀLIUM, L. Bedstraw. Cleavers.

Calyx-teeth obsolete. Corolla 4-parted, rarely 3-parted, wheel-shaped, valvate in the bud. Stamens 4, rarely 3, short. Styles 2. Fruit dry or fleshy, globular, twin, separating when ripe into the 2 seed-like, indehiscent, 1-seeded carpels.—Slender herbs, with small cymose flowers (produced in summer), square stems, and whorled leaves, the roots often containing a red coloring matter. (Name from γάλα, milk, which some species are used to curdle.)

§ 1. Naturalized species; fruit dry.

G. Mollùgo, L. Perennial, smooth throughout; stems erect or diffuse, 2 or 3° long; leaves 8, or 6 on the branchlets, oblanceolate to nearly linear; flowers very numerous in ample almost leafless panicles; fruit smooth.—Roadsides and fields, N. Y. and Penn. (Nat. from Eu.)

G. Ánglicum, Huds. Annual, slender, diffuse, seldom 1° high, glabrous; leaves 5–7, oblanceolate to nearly linear (3´´ long), their margins and the angles of the stem spinulose-scabrous; flowers rather few, cymulose on leafy branches, greenish-white, very small; fruit glabrous, more or less tuberculate.—Roadsides, Bedford Co., Va. (Curtiss). (Nat. from Eu.)

G. tricórne, With. Annual, resembling G. Aparine, rather stout, with simple branches; leaves 6 or 8, oblanceolate, cuspidate-mucronate, the margins and stem retrorsely prickly-hispid; flowers mostly in clusters of 3, dull white; fruits rather large, tuberculate-granulate, not hairy, pendulous.—Fields, eastward. (Nat. from Eu.)

§ 2. Indigenous species; fruit dry.

[*] Annual; leaves about 8 in a whorl; peduncles 1–3-flowered, axillary; fruit bristly with hooked prickles.

1. G. Aparìne, L. (Cleavers. Goose-Grass.) Stem weak and reclining, bristle-prickly backward, hairy at the joints; leaves lanceolate, tapering to the base, short-pointed, rough on the margins and midrib (1–2´ long); flowers white.—Shaded grounds, throughout the continent; probably as an introduced plant eastward.

[*][*] Perennials; leaves in 4's, comparatively large, and broad (narrower in n. 7 and 8), not cuspidate-pointed, more or less distinctly 3-nerved; fruit uncinate-hispid (except in n. 6 and 7).

[+] Peduncles loosely 3–several-flowered; flowers dull purple to yellowish-white.

2. G. pilòsum, Ait. Hairy; leaves oval, dotted, hairy (1´ long), the lateral nerves obscure; peduncles 2–3-forked, the flowers all pedicelled.—Dry copses, R. I. and Vt. to Ill., E. Kan., and southward.

Var. puncticulòsum, Torr. & Gray. Almost glabrous; leaves varying to elliptical-oblong, hispidulous-ciliate.—Va. to Tex.

3. G. Kamtscháticum, Steller. Stems weak, mainly glabrous (1° high); leaves orbicular to oblong-ovate, thin (½–1´ long), slightly pilose; flowers slenderly pedicellate; corolla glabrous, yellowish-white, not turning dark, its lobes merely acute. (G. circæzans, var. montanum, Torr. & Gray.)—Higher mountains of N. Eng., L. Canada, and far westward. (Asia.)

4. G. circæ̀zans, Michx. (Wild Liquorice.) Smooth or downy (1° high); leaves oval, varying to ovate-oblong, mostly obtuse, ciliate (1–1½´ long); peduncles usually once forked, the branches elongated and widely diverging in fruit, bearing several remote flowers on very short lateral pedicels, reflexed in fruit; lobes of the greenish corolla hairy outside, acute or acuminate.—Rich woods, N. Eng. to Minn., south to Fla. and Tex.

5. G. lanceolàtum, Torr. (Wild Liquorice.) Nearly glabrous; leaves (except the lowest) lanceolate or ovate-lanceolate, tapering to the apex (2´ long); corolla glabrous, yellowish turning dull purple, lobes more acuminate; otherwise like the last.—Dry woods, N. Eng. to N. Mich. and Minn.

7. G. Arkansànum, Gray. Similar but lower; leaves lanceolate to linear (1´ long or less), the lateral nerves obscure or none.—S. Mo. and Ark.

[+][+] Leaves narrow; flowers bright white, numerous in a compact panicle.

8. G. boreàle, L. (Northern Bedstraw.) Smooth (1–2° high); leaves linear-lanceolate; fruit minutely bristly, sometimes smooth.—Rocky banks of streams, Maine to Penn., Iowa, Minn., and westward. (Eu., Asia.)

[*][*][*] Leaves in 4's, 5's, or 6's, small, 1-nerved; flowers white; fruit smooth (flowers greenish and fruit hispid in n. 12.)

[+] Leaves pointless.

9. G. trífidum, L. (Small Bedstraw.) Stems weak, ascending (5–20´ high), branching, mostly roughened backwards on the angles; leaves in whorls of 4 to 6, linear or oblanceolate, the margins and midrib rough; peduncles scattered, 1–7-flowered; corolla-lobes and stamens often only 3.—Sphagnous bogs and wet ground, throughout the continent. Exceedingly variable.—Var. pusíllum, Gray, the smallest form; leaves only in 4's, 3–4´´ long, narrow, in age often reflexed; peduncles 1-flowered. In cold bogs, northward.—Var. latifòlium, Torr., the larger and broadest-leaved form; leaves 6 or 7´´ long, often 2´´ wide. From Canada, south and west. (Eu., Asia.)

10. G. concínnum, Torr. & Gray. Stems low and slender (6–12´ high), with minutely roughened angles; leaves all in 6's, linear, slightly pointed, veinless, the margins upwardly roughened; peduncles 2–3 times forked, diffusely panicled; pedicels short.—Dry hills, Penn. to Va., west to Minn., Iowa, and Ark.

[+][+] Leaves cuspidately mucronate or acuminate.

11. G. aspréllum, Michx. (Rough Bedstraw.) Stem much branched, rough backwards with hooked prickles, leaning on bushes (3–5° high); leaves in whorls of 6, or 4–5 on the branchlets, oval-lanceolate, with almost prickly margins and midrib; peduncles short, 2–3 times forked.—Alluvial ground, N. Eng. to N. C., west to Minn., Iowa, and Mo.

12. G. triflòrum, Michx. (Sweet-scented Bedstraw.) Stem (1–3° long) bristly-roughened backward on the angles; leaves elliptical-lanceolate, bristle pointed, with slightly roughened margins (1–2´ long); peduncles 3-flowered, the flowers all pedicelled, greenish; fruit beset with hooked bristles.—Rich woodlands, throughout the continent. Sweet-scented in drying. (Eu.)

§ 3. Perennial; fruit a berry; leaves in 4's, 1-nerved.

13. G. hispídulum, Michx. Hirsute-pubescent, scabrous, or sometimes nearly smooth, 1–2° high, diffusely branched; leaves oblong or oval, mucronate (3–6´´ long), pedicels solitary or commonly 2 or 3 from the small involucral whorl, all naked, or one of them bracteolate; flowers white; berry purple, glabrate.—Dry or sandy soil, southern N. J. to Fla., along the coast.

8. SHERÁRDIA, Dill.

S. arvénsis, L. The only species; sparingly naturalized from Eu.

Order 53. VALERIANÀCEÆ. (Valerian Family.)

Herbs, with opposite leaves and no stipules; the calyx-tube coherent with the ovary, which has one fertile 1-ovuled cell and two abortive or empty ones; the stamens distinct, 1–3, fewer than the lobes of the corolla, and inserted on its tube.—Corolla tubular or funnel-form, often irregular, mostly 5-lobed, the lobes imbricated in the bud. Style slender; stigmas 1–3. Fruit indehiscent, 1-celled (the two empty cells of the ovary disappearing), or 3-celled, two of them empty, the other 1-seeded. Seed suspended, anatropous, with a large embryo and no albumen.—Flowers in panicled or clustered cymes. (Roots often odorous and antispasmodic.)

1. VALERIÀNA, Tourn. Valerian.

Limb of the calyx of several plumose bristles (like a pappus) which are rolled up inward in flower, but unroll and spread as the seed-like 1-celled fruit matures. Corolla commonly gibbous near the base, the 5-lobed limb nearly regular. Stamens 3.—Perennial herbs, with thickened strong-scented roots, and simple or pinnate leaves. Flowers in many species imperfectly diœcious or dimorphous. (A mediæval Latin name of uncertain origin.)

[*] Root spindle-shaped, large and deep (6–12´ long); leaves thickish.

1. V. édulis, Nutt. Smooth, or minutely downy when very young; stem straight (1–4° high), few-leaved; leaves commonly minutely and densely ciliate, those of the root spatulate and lanceolate, of the stem pinnately parted into 3–7 long and narrow divisions; flowers in a long and narrow interrupted panicle, nearly diœcious; corolla whitish, obconical (2´´ long).—Wet plains and prairies, Ohio and Ont. to Iowa, Minn., and westward. June.

[*][*] Root fibrous; leaves thin. (Stems 1–3° high.)

2. V. sylvática, Banks. Smooth or minutely pubescent; root-leaves ovate or oblong, entire, rarely with 2 small lobes; stem-leaves pinnate, with 3–11 oblong-ovate or lanceolate nearly entire leaflets; cyme at first close, many-flowered; corolla inversely conical (3´´ long, rose-color or white).—Wet ground, Newf. to southern N. Y., N. Mich., westward and northward. June.

3. V. pauciflòra, Michx. Smooth, slender, surculose; root-leaves ovate, heart-shaped, toothed, pointed, sometimes with 2 small lateral divisions; stem-leaves pinnate, with 3–7 ovate toothed leaflets; branches of the panicled cyme few-flowered; tube of the (pale pink) corolla long and slender (½´ long).—Woods and alluvial banks, Penn. to S. Ill., Mo., and Tenn. June.

2. VALERIANÉLLA, Tourn. Corn Salad. Lamb-Lettuce.

[*] Corolla bluish; fruit with a corky mass at the back of the fertile cell.

V. olitòria, Poll. Fruit flattish, obliquely rhomboidal; empty cells as large as the fertile, contiguous, the thin partition at length breaking up.—Old fields, N. Y. to Penn. and La. (Nat. from Eu.)

[*][*] Corolla white; no corky mass behind the fertile cell.

[+] Fertile cell broader than the empty ones; cross-section of fruit triangular.

1. V. chenopodifòlia, DC. Stems with long internodes and few forks; glomerate cymes few, slender-peduncled; bracts broadly lanceolate; fruit glabrous or pubescent, 2´´ long. (Fedia Fagopyrum, Torr. & Gray.)—Moist grounds, western N. Y. to Minn., south to Va. and Ky.

[+][+] Fertile cell as broad as the empty ones, beaked; cross-section quadrate.

2. V. radiàta, Dufr. Fruit ovate-tetragonal, downy-pubescent (sometimes glabrous); empty cells as thick as the oblong-ovate fertile one, or thicker, a broad shallow groove between them. (Fedia radiata, Michx.)—Low grounds, Penn. to Minn., Tex., and Fla.

3. V. stenocárpa, Krok. Fruit oblong-tetragonal, commonly glabrous; oblong fertile cell thicker than the linear-oblong approximate empty ones. (Fedia stenocarpa, Engelm.)—W. Mo. and E. Kan. to Tex.

[+][+][+] Fertile cell much the narrowest, dorsally 1-nerved; section roundish.

4. V. Woodsiàna, Walp. Fruit 1´´ long or more; fertile cell ovate, tipped with a tooth; empty ones inflated, with oblong depression (sometimes an open cavity) in the middle.—Moist grounds, N. Y. and Penn. to Tex.

Var. umbilicàta, Gray. Empty cells becoming confluent, vesicular by incurvation of the circular margin, forming a deep and round umbilication. (Fedia umbilicata, Sulliv.)—N. Y. to Ohio and southward.

Var. patellària, Gray. Fruit saucer-shaped, emarginate at base and apex, winged by the divergent cells. (Fedia patellaria, Sulliv.)—Same range.

Order 54. DIPSÀCEÆ. (Teasel Family.)

Herbs, with opposite or whorled leaves, no stipules, and the flowers in dense heads, surrounded by an involucre, as in the Composite Family; but the stamens are distinct, and the suspended seed has albumen.—Represented by the following introduced species and by the cultivated Sweet Scabious (Scabiosa atropurpurea).

1. DÍPSACUS, Tourn. Teasel.

1. D. sylvéstris, Mill. (Wild Teasel.) Prickly; leaves lance-oblong; leaves of the involucre slender, longer than the head; bracts (chaff) tapering into a long flexible awn with a straight point.—Roadsides; rather rare. (Nat. from Eu.) Suspected to be the original of

2. D. Fullònum, L., the Fuller's Teasel, which has a shorter involucre, and stiff chaff to the heads, with hooked points, used for raising a nap upon woollen cloth; it has escaped from cultivation in some places. (Adv. from Eu.)

(Addendum) 2. SCABIOSA, Tourn. Scabious.

Characters of Dipsacus, but the green leaves of the involucre and involucels not rigid nor spinescent. (Name from scabies, the itch, from its use as a remedy.)

S. austràlis, Wulf. Perennial, sparsely branched, nearly glabrous, 1½–3° high; leaves narrowly lanceolate to linear, the lower oblanceolate, slightly toothed or entire; heads short-oblong; calyx obtusely short-lobed; corolla pale blue.—Central N. Y. and Penn.; rare. (Adv. from Eu.)

Order 55. COMPÓSITÆ. (Composite Family.)

Flowers in a close head (the compound flower of the older botanists), on a common receptacle, surrounded by an involucre, with 5 (rarely 4) stamens inserted on the corolla, their anthers united in a tube (syngenesious).—Calyx-tube united with the 1-celled ovary, the limb (called a pappus) crowning its summit in the form of bristles, awns, scales, teeth, etc., or cup-shaped, or else entirely absent. Corolla either strap-shaped or tubular; in the latter chiefly 5-lobed, valvate in the bud, the veins bordering the margins of the lobes. Style 2-cleft at the apex (in sterile flowers usually entire). Fruit seed-like (achene), dry, containing a single erect anatropous seed, with no albumen.—An immense family, in temperate regions chiefly herbs, without stipules, with perfect, polygamous, monœcious or diœcious flowers. The flowers with a strap-shaped (ligulate) corolla are called rays or ray-flowers; the head which presents such flowers, either throughout or at the margin, is radiate. The tubular flowers compose the disk; and a head which has no ray-flowers is said to be discoid. When the head contains two sorts of flowers it is said to be heterogamous; when only one sort, homogamous. The leaves of the involucre, of whatever form or texture, are termed scales. The bracts or scales, which often grow on the receptacle among the flowers, are called the chaff; when these are wanting, the receptacle is said to be naked.—The largest order of Phænogamous plants. The genera are divided by the corolla into three series, only two of which are represented in the Northern United States. The first is much the larger.

Systematic Synopsis.

Series I. TUBULIFLORÆ.

Corolla tubular in all the perfect flowers, regularly 5- (rarely 3–4-) lobed, ligulate only in the marginal or ray-flowers, which when present are either pistillate only, or neutral (with neither stamens nor pistil).

Tribe I. VERNONIACEÆ. Heads discoid; the flowers all alike, perfect and tubular, never yellow. Branches of the style long and slender, terete, thread-shaped, minutely bristly-hairy all over.—Leaves alternate or scattered.

1. Elephantopus. Heads 3–5-flowered, several crowded together into a compound head. Involucre of 8 scales. Pappus of several chaffy bristles.

2. Vernonia. Heads several–many-flowered, separate. Involucre of many scales. Pappus double, the inner capillary, the outer of minute chaffy bristles.

[*] Pappus a row of hard scales.

3. Sclerolepis. Head many-flowered. Scales of the involucre equal. Leaves whorled.

[*][*] Pappus of slender bristles.

[+] Achene 5-angled; bristles of the pappus roughish.

4. Mikania. Flowers and involucral scales only 4. Stems twining.

5. Eupatorium. Involucre of more than 4 scales and the flowers few or many. Stems not twining.

[+][+] Achene 10-ribbed; involucral scales striate-nerved.

6. Kuhnia. Pappus very strongly plumose. Scales of the involucre few.

7. Brickellia. Involucral scales in several series. Pappus merely scabrous.

8. Liatris. Pappus plumose or only barbellate. Corolla red-purple, strongly 5-lobed. Heads spicate or racemose, the involucre well imbricated.

9. Trilisa. Pappus minutely barbellate. Corolla rose-purple. Heads corymbed or panicled, the involucre little imbricated.

Tribe III. ASTEROIDEÆ. Heads discoid, the flowers all alike and tubular; or else radiate, the outer ones ligulate and pistillate. Anthers not caudate at base. Branches of the style in the perfect flowers flat, smooth up to where the conspicuous marginal stigmatic lines abruptly terminate, and prolonged above this into a flattened lance-shaped or triangular appendage which is evenly hairy or pubescent outside.—Leaves alternate. Receptacle naked (destitute of chaff) in all our species.

[*] 1. Ray-flowers yellow (in one species of Solidago whitish), or sometimes none at all.

[+] Pappus of not numerous slender bristles. Heads radiate. Involucre of firm scales with greenish tips, commonly coated with resin. West of the Mississippi.

10. Gutierrezia. Heads small, numerous. Ray and disk-flowers 3 or 4 each, all fertile. Pappus of several short chaffy scales. Suffrutescent; leaves very narrow.

11. Amphiachyris. Heads small. Ray-flowers 5–10; pappus coroniform. Disk-flowers infertile; pappus of several bristle-like scales. Annual; leaves very narrow.

12. Grindelia. Heads large, many-flowered. Flowers all fertile. Pappus of 2–8 rigid caducous awns. Coarse herbs with toothed leaves.

[+][+] Pappus (at least of the disk) of copious slender or capillary bristles.

[=] Pappus double.

13. Heterotheca. Resembling Chrysopsis, but the achenes of the ray thicker than those of the disk and without pappus or nearly so. Western.

14. Chrysopsis. Heads many-flowered; rays numerous. The outer pappus of very small chaffy bristles, much shorter than the inner of copious capillary bristles.

[=][=] Pappus simple.

15. Aplopappus. Heads many-flowered, many-radiate. Involucre hemispherical. Pappus of many unequal bristles. Western.

16. Bigelovia. Heads 3–4-flowered; rays none. Receptacle awl-shaped. Pappus a single row of capillary bristles.

17. Solidago. Heads few–many-flowered; rays 1–16. Pappus of numerous slender and equal capillary bristles.

18. Brachychæta. Heads 8–10-flowered, clustered; rays 4 or 5. Pappus a row of minute bristles shorter than the achene.

[*] 2. Ray-flowers white, blue, or purple, never yellow.

[+] Pappus none or very short, with or without a few awns.

[++] Receptacle conical. Awns none.

19. Bellis. Achenes marginless, flattened; pappus none. Involucral scales equal.

20. Aphanostephus. Achenes prismatic; pappus coroniform. Outer scales shorter.

21. Chætopappa. Achenes fusiform; pappus of 5 or fewer thin chaff and alternating awns. Western.

22. Boltonia. Achenes very flat, thick-winged; pappus of short bristles and usually 2–4 awns.

[+][+] Pappus of a single row of awns or coarse rigid bristles, or in the ray scale-like.

23. Townsendia. Low or stemless, with linear-spatulate leaves and large aster-like flowers.

[+][+][+] Pappus of numerous long and capillary bristles; receptacle flat.

24. Sericocarpus. Heads 12–20-flowered; rays 4 or 5. Involucre oblong or club-shaped, imbricated, cartilaginous. Achenes short, narrowed downward, silky.

25. Aster. Heads many-flowered, on leafy peduncles. Involucral scales unequal, loosely or closely imbricated. Achenes flattish; pappus simple (rarely double), copious.

26. Erigeron. Heads many-flowered, on naked peduncles. Involucre of narrow equal scales, little imbricated. Achenes flattened; pappus simple and rather scanty, or with some outer minute scales.

[*] 3. Rays none. Heads diœcious (all pistillate or all staminate).

27. Baccharis. Heads many-flowered. Pappus capillary. Smooth glutinous shrubs.

Tribe IV. INULOIDEÆ. Heads discoid (radiate only in Inula), the pistillate flowers mostly filiform and truncate. Anthers sagittate, the basal lobes attenuate into tails. Style-branches with unappendaged obtuse or truncate naked tips. Pappus capillary or none.

[*] 1. Receptacle naked. Involucre not scarious, imbricated. Not woolly.

28. Pluchea. Heads containing a few perfect but sterile flowers in the centre, and many pistillate fertile ones around them. Pappus capillary.

[*] 2. Receptacle chaffy. Involucral scales few, mostly scarious. Low floccose-woolly annuals; flowers as in n. 28.

29. Evax. Receptacle convex. Achenes obcompressed. Pappus none. Western.

30. Filago. Receptacle subulate. Achenes terete. Outer flowers without pappus.

[*] 3. Receptacle naked. Involucral scales many, scarious. Floccose-woolly herbs.

31. Antennaria. Heads diœcious. Pappus of sterile flowers club-shaped, of the fertile united at base and deciduous together.

32. Anaphalis. Heads diœcious or nearly so. Pappus not thickened above nor at all united at base.

33. Gnaphalium. Heads all fertile throughout. Pappus all capillary.

[*] 4. Corollas all somewhat broadly tubular and lobed. Involucre not scarious. Receptacle naked. Pappus none.

34. Adenocaulon. Head few-flowered and scales few; outer flowers pistillate. Somewhat woolly.

[*] 5. Heads radiate. Receptacle naked. Involucre herbaceous. Pappus copious.

35. Inula. Heads large, many-flowered. Flowers yellow. Stout perennial.

Tribe V. HELIANTHOIDEÆ. Heads radiate or discoid. Involucre not scarious (nut-like in fruit in n. 43, 44). Receptacle chaffy. Pappus never capillary, sometimes none. Anthers not caudate. Style-branches truncate or hairy-appendaged.

[*] 1. Heads radiate (obscurely so in n. 41, sometimes discoid in n. 36), the ray pistillate and fertile, the disk perfect but sterile.

[+] Achenes turgid, triangular-obovoid; pappus none.

36. Polymnia. Involucral scales in 2 rows, the 5 outer leaf-like, the inner small.

[+][+] Achenes flattened dorsally (obcompressed).

37. Silphium. Achenes wing-margined, in several rows; pappus none or 2 teeth. Scales thick, in several rows.

39. Chrysogonum. Achenes wingless, about 5; pappus a one-sided 2–3-toothed crown. Inner scales 5, chaff-like, the 5 outer longer and leaf-like.

40. Engelmannia. Achenes wingless, 8–10; pappus a scarious hispid crown. Outer scales (about 10) leaf-like, inner coriaceous with green tips. Western.

41. Parthenium. Rays 5, very short, persistent. Pappus of 2 small scales. Involucral scales short, roundish, in 2 rows.

[*] 2. Fertile flowers 1–5, the corolla none or reduced to a tube; staminate corolla funnel-form. Pappus none.

[+] Heads with 1–5 pistillate flowers. Receptacle chaffy.

42. Iva. Achenes short, thick. Involucre of few roundish scales.

[+][+] Heads of two sorts on the same plant, the upper staminate with an open cup-shaped involucre, the lower pistillate, of 1–4 flowers in a closed bur-like involucre.

43. Ambrosia. Scales of staminate involucre united. Fruit 1-seeded.

44. Xanthium. Scales of staminate involucre distinct. Fruit 1–4-celled, 1–4-beaked.

[*] 3. Heads radiate, or rarely discoid; disk-flowers all perfect and fertile. Anthers blackish. Pappus none, or a crown or cup, or of one or two chaffy awns, never capillary, nor of several uniform chaffy scales.—Leaves more commonly opposite.

[+] Involucre double; the outer forming a cup.

45. Tetragonotheca. Outer involucre 4-leaved. Achenes obovoid; pappus none.

[+][+] Involucre of one or more rows of separate scales.

[++] Chaff of the flat receptacle bristle-shaped.

46. Eclipta. Ray short. Involucral scales 10–12, in two rows, herbaceous.

[++][++] Chaff scale-like, embracing or subtending the achenes.

[=] Receptacle high, conical or columnar in fruit. Pappus none or a short crown.

47. Heliopsis. Rays fertile. Achenes 4-sided. Leaves opposite.

48. Echinacea. Rays rose-colored, pistillate, sterile. Achenes short, 4-sided. Chaff spinescent.

49. Rudbeckia. Rays neutral. Achenes 4-sided, flat at the top, marginless.

50. Lepachys. Rays few, neutral. Achenes flattened laterally and margined.

[=][=] Receptacle flat to convex. Achenes not winged nor very flat.

51. Borrichia. Achenes 3–4-angled; pappus a short 4-toothed crown. Shrubby.

52. Helianthus. Achenes flattened, bearing 2 very deciduous chaffy pointed scales.

[=][=][=] Receptacle convex (rarely conical). Achenes flat-compressed laterally, winged or wingless, 2-awned. Leaves decurrent.

53. Verbesina. Involucral scales closely imbricated in 2 or more rows.

54. Actinomeris. Scales few, soon deflexed. Achenes obovate, squarrosely spreading.

[*] 4. Rays few, neutral, or wanting. Achenes obcompressed, i.e., flattened parallel with the scales of the involucre (rarely terete). Involucre double; the outer spreading and often foliaceous. Receptacle flat. Leaves opposite.

55. Coreopsis. Pappus of 2 (or rarely more) scales, teeth, or awns, which are naked or barbed upward, sometimes obsolete or a mere crown.

56. Bidens. Pappus of 2 or more rigid and persistent downwardly barbed awns or teeth.

57. Thelesperma. Inner involucre connate to the middle. Achenes terete. Awns retrorsely bearded.

[*] 5. Heads radiate or discoid; disk-flowers all perfect and fertile. Achenes turbinate, 5-angled; pappus of several chaffy scales.

[+] Leaves alternate, entire. Disk-flowers purplish.

58. Baldwinia. Rays numerous, long, neutral. Involucre much imbricated. Receptacle deeply honey-combed.

59. Marshallia. Rays none. Involucre of narrow leafy equal scales. Receptacle chaffy.

60. Galinsoga. Rays few, short, pistillate, whitish. Involucre of 4–5 thin ovate scales. Receptacle chaffy.

Tribe VI. HELENIOIDEÆ. Nearly as Tribe V., but receptacle not chaffy (somewhat so in n. 64). In our genera, the disk-flowers perfect and fertile; the pappus a row of several chaffy scales (bristly-dissected in n. 65); the involucre hardly at all imbricated (partly scarious in n. 61).

[*] Involucral scales distinct, not glandular-punctate.

61. Hymenopappus. Rays none. Receptacle flat. Involucre colored. Western.

62. Actinella. Rays fertile, 3-toothed. Receptacle elevated. Involucre appressed. Western.

63. Helenium. Rays fertile or sterile, 3–5-cleft. Receptacle elevated. Involucre small, reflexed. Leaves decurrent.

64. Gaillardia. Ray 3-toothed, or none. Receptacle usually beset with fine fimbrillate chaff. Outer involucral scales loose and leafy. Pappus-chaff tipped with the projecting midvein. Western.

[*][*] Dotted with oil-glands. Involucral scales united into a cup.

65. Dysodia. Pappus a row of chaffy scales dissected into many bristles.

Tribe VII. ANTHEMIDEÆ. Distinguished from the last two tribes by the more or less dry and scarious imbricated scales of the involucre. Heads radiate (ray mostly white) or discoid, the perfect flowers sometimes sterile and the pistillate rarely tubular. Achenes small; pappus a short crown or none.—Mostly strong-scented; leaves alternate.

[*] Receptacle chaffy, at least in part. Heads radiate, many-flowered.

66. Anthemis. Achenes terete, angled or ribbed. Heads hemispherical, rather large.

67. Achillea. Achenes obcompressed. Heads small, campanulate or obovate.

[*][*] Receptacle naked.

[+] Heads rather large, pedunculate, radiate or rarely rayless.

68. Matricaria. Receptacle conical. Rays pistillate or none. Pappus crown-like or none.

69. Chrysanthemum. Receptacle flattish. Rays many, pistillate. Pappus none.

[+][+] Heads mostly small, discoid, corymbed or paniculate.

70. Tanacetum. Heads corymbed. Achene with broad summit; pappus a short crown.

71. Artemisia. Heads in panicled spikes or racemes. Achenes with narrow summit; pappus none.

Tribe VIII. SENECIONIDEÆ. Heads radiate or discoid, the involucre little or not at all imbricated, not scarious. Receptacle naked. Anthers tailless. Pappus capillary.

[*] Heads monœcious or subdiœcious, the perfect flowers mostly sterile, and the small (ligulate or tubular) ray-flowers in more than one row (at least in the fertile heads). Style-branches obtuse, not appendaged nor hispid. Leaves all radical.

72. Tussilago. Head solitary, yellow-flowered, monœcious.

73. Petasites. Heads corymbed, subdiœcious. Flowers white or purplish.

[*][*] Flowers all fertile. Style-branches truncate or capitellate, often appendaged. Involucral scales connivent-erect.

[+] Leaves opposite.

74. Arnica. Heads showy. Pappus rather rigid, scabrous.

[+][+] Leaves alternate. Pappus soft-capillary, copious.

75. Senecio. Heads usually radiate. Corollas yellow, 5-toothed.

76. Cacalia. Heads discoid. Corollas white or cream-colored, 5-cleft.

77. Erechtites. Heads discoid. Flowers whitish, the outer pistillate with filiform corollas.

[*] Achenes attached by the base. Flowers all alike.

[+] Leaves not prickly. Style-branches partly distinct. Filaments glabrous.

78. Arctium. Involucral scales hooked at the tip. Pappus of short rough bristles.

[+][+] Leaves prickly. Style-branches coherent, usually a pubescent ring below.

79. Cnicus. Pappus bristles plumose. Receptacle densely bristly.

80. Carduus. Pappus-bristles not plumose. Receptacle densely bristly.

81. Onopordon. Pappus-bristles not plumose. Receptacle deeply honeycombed.

[*][*] Achenes attached obliquely. Marginal flowers often enlarged and ray-like.

82. Centaurea. Involucral scales appendaged. Pappus double and bristly, or very short or none.

Series II. LIGULIFLORÆ.

Tribe X. CICHORIACEÆ.

Corolla ligulate in all the flowers of the head, and all the flowers perfect.—Herbs, with milky juice. Leaves alternate.

[*] Pappus none.

83. Lampsana. Involucre cylindrical, of 8 scales in a single row, 8–12-flowered.

[*][*] Pappus chaffy, or of both chaff and bristles.

84. Krigia. Involucre simple, not calyculate. Pappus of both chaff and bristles.

85. Cichorium. Involucre double. Pappus a small crown of many bristle-form scales.

[*][*][*] Pappus plumose.

86. Tragopogon. Involucre simple, not calyculate. Achenes long-beaked. Stems leafy.

87. Leontodon. Involucre calyculate. Achenes fusiform. Leaves radical.

88. Picris. Outer involucral scales spreading. Achenes terete. Stems leafy.

[*][*][*][*] Pappus composed entirely of capillary bristles, not plumose.

[+] Achenes not flattened, columnar or terete, often slender.

[++] Achenes not beaked.

[=] Flowers yellow or orange.

89. Hieracium. Involucre imbricated. Pappus tawny. Pilose perennials.

90. Crepis. Involucral scales in one row. Pappus white, soft. Not pilose.

[=][=] Flowers white or cream color or pinkish. Involucre calyculate.

91. Prenanthes. Achenes short, blunt. Pappus tawny or brown. Stems leafy and heads often nodding.

92. Lygodesmia. Achenes long, tapering. Pappus white. Stems nearly leafless; heads erect. Western.

[++][++] Achenes beaked (sometimes beakless in n. 93). Flowers yellow.

93. Troximon. Scapose. Involucre loosely imbricated. Achenes 10-ribbed.

94. Taraxacum. Scapose. Involucre calyculate. Achenes 4–5-ribbed.

95. Pyrrhopappus. Scapose or branched. Pappus reddish, the base surrounded by a soft villous ring.

96. Chondrilla. Stem branching, leafy. Involucre few-flowered, calyculate. Pappus white.

[+][+] Achenes flat or flattish. Pappus white, fine and soft. Involucre imbricated. Leafy-stemmed, with panicled heads.

97. Lactuca. Achenes more or less beaked. Flowers yellow or purplish.

98. Sonchus. Achenes flattish, not at all beaked. Flowers yellow.

Artificial Key to the Genera of the Tubulifloræ.

§ 1. Rays or ligulate flowers none; corollas all tubular (or rarely none).

[*] 1. Flowers of the head all perfect and alike.

Pappus composed of bristles:

Double, the outer of very short, the inner of longer bristles No. 2

Simple, the bristles all of the same sort.

Heads few-flowered, themselves aggregated into a compound or dense cluster 1

Heads separate, few-flowered or many-flowered.

Receptacle (when the flowers are pulled off) bristly-hairy 78, 79, 80

Receptacle deeply honeycomb-like 81

Receptacle naked.

Pappus of plumose or bearded stiff bristles. Flowers purple 8

Pappus of very plumose bristles. Flowers whitish 6

Pappus of slender but rather stiff rough bristles 4, 5, 7, 9, 16

Pappus of very soft and weak naked bristles 76, 77

Pappus composed of scales or chaff.

Receptacle naked. Leaves in whorls 3

Receptacle naked. Leaves alternate, dissected 61

Receptacle bearing chaff among the flowers 59, 64

Pappus of 2 or few awns or teeth 53, 57, barbed in 55, 56

Pappus none, or a mere crown-like margin to the fruit 36, 68, 71

[*] 2. Flowers of two kinds in the same head.

Marginal flowers neutral and sterile, either conspicuous or inconspicuous 82

Marginal flowers pistillate and fertile.

Receptacle elongated and bearing broad chaff among the flowers 29, 30

Receptacle convex, chaffy. Achene flat, 2-awned 52

Receptacle naked or bearing no conspicuous chaff.

Pappus of capillary bristles. Involucre imbricated 28, 32, 33

Pappus of capillary bristles. Involucre merely one row of scales 26, 73, 77

Pappus a short crown or none.

Achenes becoming much longer than the involucre 34

Achenes not exceeding the involucre 42, 70, 71

[*] 3. Flowers of two kinds in separate heads, the one pistillate, the other staminate.

Heads diœcious; in both kinds many-flowered. Pappus capillary 27, 31, 32, 79

Heads monœcious; the fertile 1–2-flowered and closed. Pappus none 43, 44

§ 2. Rays present; i.e. the marginal flowers or some of them with ligulate corollas.

[*] 1. Pappus of capillary bristles, at least in the disk. (Rays all pistillate.)

Rays occupying several rows 26, 72, 73

Rays in one marginal row, and

White, purple or blue, never yellow 17, 24, 25, 26, 73

Yellow, of the same color as the disk.

Pappus (at least in the disk) double, the outer short and minute 13, 14

Pappus simple.

Scales of the involucre equal and all in one row. Leaves alternate 75

Scales of the involucre in two rows. Leaves opposite 74

Scales of the involucre imbricated. Leaves alternate 10, 11, 15, 17, 35

[*] 2. Pappus a circle of awns or rigid bristles (at least in the disk).

Ray yellow, awns few (2–8) 12

Ray rose-color 23

[*] 4. Pappus a circle of thin chaffy scales or short chaffy bristles.

Heads several-flowered. Receptacle chaffy 60

Heads 8–10-flowered. Receptacle naked 18

Heads many-flowered. Receptacle deeply honeycombed 58

Heads many-flowered. Receptacle naked 62, 63

Heads many-flowered. Receptacle chaffy 64

[*] 5. Pappus none, or a cup or crown, or of 2 or 3 awns, teeth, or chaffy scales corresponding with the edges or angles of the achene, often with intervening minute bristles or scales.

[+] Receptacle naked.

Achene flat, wing-margined. Pappus of separate little bristles and usually 2–4 awns 22

Achene flat, marginless. Pappus none. Receptacle conical 19

Achene terete or angled. Pappus none. Receptacle flattish 69

Achene angled. Pappus a little cup or crown (or none). Receptacle conical 20, 68

Achene fusiform. Pappus of few scales, usually with alternating awns 21

[+][+] Receptacle chaffy.

Rays neutral (rarely pistillate but sterile); the disk-flowers perfect and fertile.

Receptacle mostly elevated (varying from convex to columnar), and

Chaffy only at the summit; the chaff deciduous. Pappus none 66

Chaffy throughout. Achene flattened laterally if at all 48, 49, 50, 52, 54

Receptacle flat or flattish. Achene flattened, parallel with the scales or chaff 55, 56

Receptacle flat. Achene terete, 2-awned 57

Rays pistillate and fertile; the disk-flowers also perfect and fertile.

Achene much flattened laterally, 1–2-awned 53

Achene flattened parallel with the scales and chaff. Pappus none 67

Achene 3–4-angular, terete or laterally flattish, awnless.

Receptacle convex or conical. Leaves alternate, dissected 66

Receptacle conical. Leaves opposite, simple.

Achene obovoid. Involucre a leafy cup 45

Achene 4-angular. Involucre of separate scales 47

Receptacle flat. Leaves opposite and simple 46, 51

Rays pistillate and fertile; the disk-flowers staminate and sterile (pistil imperfect).

Receptacle chaffy 36–41

1. ELEPHÁNTOPUS, L. Elephant's-foot.

Heads discoid, 2–5-flowered, several together clustered into a compound pedunculate head; flowers perfect. Involucre narrow, flattened, of 8 oblong dry scales. Achenes 10-ribbed; pappus of stout bristles, chaffy-dilated at the base.—Perennials, with alternate leaves and purplish flowers. (Name composed of ἔλεφας, elephant, and ποῦς, foot.)

[*] Stem leafy; upper leaves very like the basal.

1. E. Caroliniànus, Willd. Somewhat hairy, corymbose, leafy; leaves ovate-oblong, thin.—Dry soil, Penn. to Ill. and Kan., and southward.

[*][*] Stem scape-like, with a few bract-like leaves or naked.

2. E. tomentòsus, L. Somewhat hairy; basal leaves obovate to narrowly spatulate, silky and prominently veined beneath; heads large; pappus-scales attenuate.—Va., Ky., and southward.

3. E. nudàtus, Gray. Strigose-puberulent; basal leaves thin, green, spatulate-obovate or oblanceolate, not prominently veined beneath; heads smaller; pappus scales broadly deltoid.—Del. and southward.

Heads discoid, 15–many-flowered, in corymbose cymes; flowers perfect. Involucre shorter than the flowers, of many much imbricated scales. Receptacle naked. Achenes cylindrical, ribbed; pappus double, the outer of minute scale-like bristles, the inner of copious capillary bristles.—Perennial herbs, with leafy stems, alternate and acuminate or very acute leaves and mostly purple flowers. Species very difficult. (Named for Wm. Vernon, an early English botanist who travelled in this country.)

[*] Heads large, 50–70-flowered.

1. V. Arkansàna, DC. Tall, rather glabrous; leaves linear-lanceolate, retrorsely denticulate; involucre very squarrose, the scales with long filiform tips.—Mo., Kan., and southward.

[*][*] Heads ½´ high or less, 15–40-flowered.

[+] Leaves narrowly linear, glabrous, veinless, mostly entire.

2. V. Jamèsii, Torr. & Gray. Low, nearly glabrous; heads few-flowered; scales obtuse or acute.—Plains of Neb. and southward.

[+][+] Leaves broader, mostly sharply denticulate or rigidly serrate, veined.

3. V. fasciculàta, Michx. Leaves linear to oblong-lanceolate; heads many, crowded; scales close, obtuse or the uppermost mucronate; achene smooth.—Low grounds, Ohio and Ky. to Dak., and southward. Aug.

4. V. altíssima, Nutt. Usually tall; leaves lanceolate or lance-oblong; cyme loose; scales close, obtuse or mucronate; achenes hispidulous on the ribs.—Low grounds, W. Penn. to Ill., and southward.—Heads variable, 2–4´´ high and the scales in few or many ranks; the var. grandiflòra, Nutt., with large heads, the involucre of 35–40 scales in many ranks.

5. V. Noveboracénsis, Willd. Rather tall; leaves long-lanceolate to lance-oblong; cyme open; involucre usually purplish; scales ovate and lance-ovate tipped with a slender cusp or awn.—Low grounds near the coast, Maine to Va., west to Minn., E. Kan., and southward. Aug.

Var. latifòlia, Gray. Leaves broader; heads few; scales merely acute or acuminate.—Penn. to Ohio and southward.

6. V. Baldwínii, Torr. Tomentulose; heads small, at first globose; leaves lance-oblong or -ovate; involucre hoary-tomentose, greenish, squarrose, the scales acute or acuminate.—Prairies and barren hills; E. Mo. to Kan. and Tex. July, Aug. Passes into n. 4.

3. SCLERÓLEPIS, Cass.

Head discoid, many-flowered; flowers perfect. Involucral scales linear, equal, in 1 or 2 rows. Receptacle naked. Corolla 5-toothed. Achenes 5-angled; pappus a single row of 5 almost horny oval and obtuse scales.—A smooth perennial, with simple stems, rooting at the base, linear entire leaves in whorls of 4–6, and a terminal head of flesh-colored flowers. (Name composed of σκληρός, hard, and λεπίς, a scale, from the pappus.)

1. S. verticillàta, Cass.—In water; pine barrens, New Jersey and southward. Aug.

Heads discoid, 4-flowered. Involucre of 4 scales. Receptacle small. Flowers, achenes, etc., as in Eupatorium.—Twining perennials, climbing bushes, with opposite commonly heart-shaped and petioled leaves, and corymbose-panicled flesh-colored flowers. (Named for Prof. Mikan, of Prague.)

1. M. scándens, L. Nearly smooth, twining; leaves somewhat triangular-heart-shaped or halberd-form, pointed, toothed at the base.—Copses along streams, E. New Eng. to Ky., and southward. July–Sept.

5. EUPATÒRIUM, Tourn. Thoroughwort.

Heads discoid, 3–many-flowered; flowers perfect. Involucre cylindrical or bell-shaped, of more than 4 scales. Receptacle flat or conical, naked. Corolla 5-toothed. Achenes 5-angled; pappus a single row of slender capillary barely roughish bristles.—Erect perennial herbs, often sprinkled with bitter resinous dots, with generally corymbose heads of white, bluish, or purple blossoms, appearing near the close of summer. (Dedicated to Eupator Mithridates, who is said to have used a species of the genus in medicine.)

§ 1. EUPATORIUM proper. Receptacle flat.

[*] Heads cylindrical, 5–15-flowered; the purplish scales numerous, closely imbricated in several rows, of unequal length, slightly striate; stout herbs, with ample mostly whorled leaves, and flesh-colored flowers.

1. E. purpùreum, L. (Joe-Pye Weed. Trumpet-Weed.) Stems tall and stout, simple; leaves 3–6 in a whorl, oblong-ovate or lanceolate, pointed, very veiny, roughish, toothed; corymbs very dense and compound.—Varies greatly in size (2–12° high), etc., and with spotted or unspotted, often dotted stems, etc.,—including several nominal species.—Low grounds; common.

Var. amœ̀num, Gray. Low; leaves fewer, ovate or oblong; heads few, 3–5-flowered.—Mountains of Va. and N. Y.

[*][*] Heads 3–20-flowered; involucre 8–15 more or less imbricated and unequal scales, the outer ones shorter; flowers white.

[+] Leaves all alternate, mostly dissected; heads panicled, very small, 3–5-flowered.

2. E. fœniculàceum, Willd. (Dog-Fennel.) Smooth or nearly so, paniculately much-branched (3–10° high); leaves 1–2-pinnately parted, filiform.—Va., near the coast, and southward. Adv. near Philadelphia.

[+][+] Leaves long-petioled, the upper ones alternate; heads 12–15-flowered, in compound corymbs.

3. E. serótinum, Michx. Stem pulverulent-pubescent, bushy-branched (3–7° high); leaves ovate-lanceolate, tapering to a point, triple-nerved and veiny, coarsely serrate (3–6´ long); involucre very pubescent.—Alluvial ground, Md. to Minn., E. Kan., and southward.

[+][+][+] Leaves sessile or nearly so, with a narrow base, mostly opposite; heads mostly 5-flowered.

[=] Involucral scales with white and scarious acute tips.

Var. subvenòsum, Gray. Less rough; leaves 1–2´ long, finely toothed and less veiny.—Long Island and N. J.

5. E. leucólepis, Torr. & Gray. Minutely pubescent, simple (1–2° high); leaves linear-lanceolate, closely sessile, 1-nerved, obtuse, minutely serrate, rough both sides; corymb hoary.—Sandy bogs, Long Island, N. J., and southward.

[=][=] Scales not scarious or obscurely so, obtuse, at length shorter than the flowers.

6. E. hyssopifòlium, L. Minutely pubescent (1–2° high); leaves narrow, linear or lanceolate, elongated, obtuse, 1–3-nerved, entire, or the lower toothed, often crowded in the axils, acute at the base.—Sterile soil, Mass. to Va., E. Ky., and southward.

Var. laciniàtum, Gray. Leaves irregularly and coarsely toothed or laciniate.—Penn., Ky., and southward.

7. E. semiserràtum, DC. Minutely velvety-pubescent, branching (2–3° high); leaves lanceolate or oblong, triple-ribbed and veiny, serrate above the middle, tapering to the base, the lower slightly petioled; heads small. (E. parviflorum, Ell.)—Damp soil, Va. to Ark., and southward.—Leaves sometimes whorled in threes, or the upper alternate.

8. E. altíssimum, L. Stem stout and tall (3–7° high), downy; leaves lanceolate, tapering at both ends, conspicuously 3-nerved, entire, or toothed above the middle, the uppermost alternate; corymbs dense; scales of the involucre obtuse, shorter than the flowers.—Dry soil, Penn. to Minn. and Ky.—Leaves 3–4´ long, somewhat like those of a Solidago.

[+][+][+][+] Leaves sessile or nearly so, with a broad base, opposite or in threes; heads pubescent.

[=] Heads 5–8-flowered; leaves not clasping.

9. E. teucrifòlium, Willd. Roughish-pubescent (2–8° high); leaves ovate-oblong and ovate-lanceolate, obtuse or truncate at base, slightly triple-nerved, veiny, coarsely toothed or incised toward the base, the lower shortly petioled, the upper alternate; branches of the corymb few, unequal; scales of the involucre oblong-lanceolate, at length shorter than the flowers.—Low grounds, Mass. to Va., and southward near the coast.

10. E. rotundifòlium, L. Downy-pubescent (2° high); leaves roundish-ovate, obtuse, truncate or slightly heart-shaped at the base, deeply crenate-toothed, triple-nerved, veiny, roughish (1–2´ long); corymb large and dense; scales of the (5-flowered) involucre linear-lanceolate, slightly pointed.—Dry soil, R. I. to Va., near the coast, and southward.