[*][*][*] _Stigma clavate; stem somewhat quadrangular with 2--4 ridges or hairy lines decurrent from some of the leaves._

[+] _Tall and mostly branching, many-flowered; leaves rather large, toothed, not revolute, the lower opposite; seeds papillose._

4. E. coloratum, Muhl. Somewhat h.o.a.ry-p.u.b.escent above or glandular, 1--3 high; leaves lanceolate, sharply serrulate or denticulate, acute, narrowed to conspicuous petioles; flowers pale, more or less nodding; peduncles shorter than the leaves; seeds dark, unappendaged; coma cinnamon-color.--Wet places, common.

5. E. adenocaulon, Haussk. Differs in its more glandular p.u.b.escence above, the often blunter and less toothed leaves abruptly contracted to shorter petioles, flowers erect, paler seeds with a slight prolongation at top, and a merely dingy coma.--Wet places through the Northern States.

6. E. glandulsum, Lehm. Subsimple; p.u.b.escence above not glandular; leaves ovate-lanceolate, mostly abruptly rounded to a sessile base and more glandular-toothed; seeds larger.--Canada to the mountains of N. C.

(_fide_ Haussknecht). (Asia.)

[+][+] _Mostly low, slender and simple (except forms of n. 10); leaves chiefly opposite, less toothed; flowers few, nodding; seeds appendaged at the apex._

[++] _Seeds areolate but not papillose; leaves not revolute._

7. E. anagallidiflium, Lam. Glabrate, a span high or less; leaves erect or ascending, about equalling the internodes, elliptical-oblong to narrowly obovate, entire or the upper denticulate, tapering to short petioles; flowers purple; sepals rather obtuse; capsules glabrous on peduncles exceeding the leaves.--White Mts. and Adirondacks (_fide_ Haussknecht). (Eu.)

8. E. lactiflrum, Haussk. Glabrous except the p.u.b.escent lines, 6--12'

high, with elongated internodes; leaves elliptical or the lowest round-obovate, slightly repand-denticulate, obtuse, tapering into mostly elongated petioles; flowers smaller, white; sepals more acute; seeds more prominently appendaged.--White Mts., and northward (_fide_ Haussknecht). (Eu.)

[++][++] _Seeds papillose-roughened._

9. E. Hornemanni, Reichenb. Glabrate, 8--18' high; leaves mostly horizontal, ovate, the upper acutish, remotely denticulate, abruptly contracted to winged petioles, not revolute; seeds often only slightly roughened, short and shortly appendaged. (E. alpinum, _Man._)--White Mts., dells of the Wisconsin River (_Lapham_), and northward. (Eu.)

10. E. pal.u.s.tre, L. Slender, 1 high or less, often branched, finely p.u.b.escent; leaves erect or ascending, about equalling or longer than the internodes, sessile, linear to linear-lanceolate or elliptic-oblong, obtuse, with revolute margins; capsules p.u.b.escent to nearly glabrous, mostly shorter than the slender peduncles; seeds fusiform, with long beak. (E. pal.u.s.tre, var. lineare, _Man._, in part.)--Penn. to Minn. and the White Mts., north and westward. (Eu.)

4. NOTHeRA, L. EVENING PRIMROSE.

Calyx-tube prolonged beyond the ovary, deciduous; the lobes 4, reflexed.

Petals 4. Stamens 8; anthers mostly linear and versatile. Capsule 4-valved, many-seeded. Seeds naked.--Leaves alternate. Flowers yellow, white or rose-color. (An old name, of unknown meaning, for a species of Epilobium.)

-- 1. _Stigma-lobes linear, elongated (except in n. 7); calyx-tube linear, slightly dilated at the throat; anthers linear._

[*] _Caulescent annuals or biennials; flowers erect in the bud, nocturnal, yellow, the calyx-tips free; capsules sessile, coriaceous; seeds in two rows in each cell._

[+] _Flowers in a leafy spike; capsules stout, oblong, slightly narrowed above._

1. . biennis, L. (COMMON EVENING PRIMROSE.) Rather stout, erect (1--5 high), usually simple, more or less p.u.b.escent and hairy; leaves lanceolate to oblong- or rarely ovate-lanceolate (2--6' long), acute or ac.u.minate, repandly denticulate, the lowest petioled; calyx-tube 1--2'

long, the tips of the sepals contiguous; petals --' long; capsule more or less p.u.b.escent or hirsute.--Throughout the U. S.--Var. CRUCIaTA, Torr. & Gray, with small narrow petals, appears to be merely a rare garden (?) sport. E. Ma.s.s.

Var. grandiflra, Lindl., has petals as long as the calyx-tube (1--2'

long).--Same range as the type, but not so common east.

2. . Oakesiana, Robbins. Annual, more slender, not hairy, the p.u.b.erulence mainly appressed; calyx-tips not contiguous at base; otherwise nearly as in the typical form of the last. (. biennis, var.

Oakesiana, _Gray._)--Dry places, E. Ma.s.s., R. I., and Conn.

[+][+] _Flowers in a leafy spike or axillary; capsules linear._

3. . rhombipetala, Nutt. Rarely branching, appressed-p.u.b.erulent and subcanescent; leaves narrowly lanceolate, ac.u.minate, denticulate, the lowest attenuate to a petiole and rarely pinnatifid, diminishing upward into the close, elongated, conspicuously bracted spike; calyx silky-canescent (tube 1' long); petals rhombic-ovate (6--10'

long).--Ind. to Minn. and Ark.

4. . humifusa, Nutt. Stems dec.u.mbent or ascending (--2 long); _h.o.a.ry-p.u.b.escent with short dense appressed hairs; leaves_ narrowly lanceolate or oblanceolate (--1' long), _sparingly repand-dentate or entire_, the radical leaves pinnatifid, the floral not reduced; capsule --1' long, silky, curved; seeds smooth.--On the sea-coast, N. J. to Fla.

5. . sinuata, L. Stems ascending or dec.u.mbent, simple or branched (1 high or more), _more or less strigose-p.u.b.escent_ and p.u.b.erulent; _leaves_ oblong or lanceolate (1--2' long), _sinuately toothed or often pinnatifid_, the floral similar; capsule 1--1' long; _seeds strongly pitted_.--N. J. to Fla., west to E. Kan. and Tex. Very variable.

[*][*] _Caulescent perennial; flowers axillary, nodding in the bud, white turning rose-color; capsules sessile, linear; seeds in a single row._

6. . albicaulis, Nutt. Stems erect (--4 high), simple or branched, white and often shreddy, glabrous or p.u.b.erulent; leaves linear to oblong-lanceolate (1--3' long), entire or repand-denticulate, or sinuate-pinnatifid toward the base; calyx-tips free, throat naked; pods --2' long, often curved or twisted; seeds lance-linear, smooth.--W. Minn. to N. Mex., and westward.

[*][*][*] _Caulescent; flowers diurnal, yellow and erect in the bud (except in n. 11); capsules obovate or clavate, quadrangular, the valves ribbed and the angles more or less strongly winged (except in n. 7)._

7. . liniflia, Nutt. Annual or biennial, erect, very slender, simple or diffuse (6--15' high), glabrous, the branchlets and capsules p.u.b.erulent; radical leaves oblanceolate, _cauline linear-filiform_ --1'

long; spikes loosely flowered; corolla 2--3" long; _stigmas short; capsules_ obovate to oblong-clavate, 2--3" long, _not winged_, nearly sessile.--Ill. to E. Kan., La., and Tex.

8. . pumila, L. Biennial, p.u.b.erulent, 1--2 high; _leaves_ mostly glabrous, _entire_, obtuse, the radical spatulate, the _cauline narrowly oblanceolate_; _flowers loosely spiked_; corolla 4--12" long; _capsule glabrous_, oblong-clavate, 3--6" long, sessile or on a short pedicel, _slightly winged_. (Incl. . chrysantha, _Michx._)--Dry fields, N. Scotia to N. J., west to Minn. and Kan. June.

9. . fruticsa, L. (SUNDROPS.) Biennial or perennial, erect, often tall and stout (1--3 high), villous-p.u.b.escent or p.u.b.erulent or nearly glabrous; leaves oblong- to linear-lanceolate, _mostly denticulate; raceme corymbed or loose_; petals 9--12" long; _capsule subsessile or with a pedicel shorter than itself_, prominently ribbed and _strongly winged_.--Common and very variable.

Var. linearis, Watson. Leaves linear to linear-lanceolate; capsule usually shorter than the pedicel, rather less broadly winged. (.

linearis of _Man._, in part. . riparia, _Nutt._)--Conn. to Fla., west to Mo. and La.

Var. humifusa, Allen. Low, dec.u.mbent, somewhat woody, diffusely branched, p.u.b.erulent; branches slender, flexuous; leaves narrow; flowers few, small; capsules p.u.b.escent, about equalling the pedicel. (.

linearis of _Man._, in part.)--Suffolk Co., L. Island.

10. . glauca, Michx. Perennial, erect (2--3 high), _glabrous and glaucous; leaves ovate to ovate-oblong_ (2--4' long), repand-denticulate; _flowers in short leafy corymbs; petals 9--15"

long; capsule_ glabrous, ovoid-oblong, _very broadly winged_, usually abruptly contracted into a pedicel equalling or shorter than itself.--Mountains of Va. to Ala., west to Ky. and E. Kan.

11. . specisa, Nutt. Perennial, erect or subdec.u.mbent, finely p.u.b.escent; leaves oblong-lanceolate to linear, repand-denticulate, or more or less deeply sinuate-pinnatifid; _flowers large, white or rose_; capsule clavate-obovate, strongly 8-ribbed, rigid, acute, stoutly pedicelled.--Mo. to Kan. and Tex.

[*][*][*][*] _Capsule oblong to ovate or orbicular, broadly winged, rigid and sessile._

[+] _Acaulescent or nearly so; flowers white or rose-color._

12. . triloba, Nutt. Biennial or perennial, nearly glabrous; leaves 2--10' long, somewhat ciliate, long-petioled, runcinate-pinnatifid or oblanceolate and only sinuate-toothed; calyx-tips free, the tube slender (2--4' long); petals 6--12" long; capsule ovate, --1' long, strongly winged, net-veined.--Ky. to Miss. and Tex., west to the Pacific.

Var. (?) parviflra, Watson. Flowers very small (1--2' long), fertilized in the bud and rarely fully opening; fruit abundant, forming at length a densely crowded hemispherical or cylindrical ma.s.s nearly 2' in diameter and often 2--3' high.--Plains of Kan. and Neb.

[+][+] _Low caulescent perennials; flowers axillary, yellow._

13. . Missouriensis, Sims. Stems dec.u.mbent; p.u.b.escence short and silky, closely appressed, sometimes dense or wholly wanting; leaves thick, oval to linear, mostly narrowly lanceolate (2--5' long), ac.u.minate, entire or repand-denticulate; calyx-tube 2--5' long; petals broad, 1--2' long; capsules...o...b..cular, very broadly winged (1--3' long).--Mo. and Kan. to Tex.

14. . Fremontii, Watson. h.o.a.ry with appressed silky p.u.b.escence; leaves linear, pointed, entire; calyx-tube 1--2' long; petals --1' long; capsule h.o.a.ry, oblong, narrowed at base, 9" long.--Central Kan.

-- 2. _Stigma discoid; calyx-tube more broadly dilated above; anthers oblong-linear; capsule mostly sessile, linear-cylindric; perennial, somewhat woody, with axillary yellow flowers._

15. . Hartwegi, Benth., var. lavandulaeflia, Watson. Stems numerous from a woody base, 3--6' high; _leaves numerous, h.o.a.ry-p.u.b.erulent_, mostly linear, --1' long; _calyx-tube 1--2' long_; capsule 8--10"

long.--Central Kan. to Col. and N. Mex.