[+][+] Stigma small, naked, often beaked or pointed.
[++] Rootstock fleshy and thickened, never filiform nor producing runners; flowers violet or purple (rarely white); lateral petals bearded.
2. V. pedatífida, G. Don. Leaves all palmately or pedately 5–7-parted; divisions 2–3-cleft; lobes linear; otherwise like n. 3. (V. delphinifolia, Nutt.)—Rich prairies, or more often in dry poor land, Ill. to Kan. and Minn.
3. V. palmàta, L. (Common Blue V.) Glabrous to villous-pubescent; early leaves roundish-cordate or reniform and merely crenate, the sides rolled inward when young, the later very various, palmately or pedately or hastately lobed or parted, the segments obovate to linear. (V. cucullata, var. palmata, Gray.)—Moist or dryish, especially sterile, ground; very common.
Var. cucullàta, Gray. Later leaves merely crenate, not lobed. (V. cucullata, Ait.)—Low grounds; common everywhere. Both forms are very variable in the size and shape of the leaves and sepals, and in the size and color of the flowers, which are deep or pale violet-blue or purple, sometimes white or variegated with white.
4. V. sagittàta, Ait. (Arrow-leaved V.) Smoothish or hairy; leaves on short and margined, or the later often on long and naked petioles, varying from oblong-heart-shaped to halberd-shaped, arrow-shaped, oblong-lanceolate or ovate, denticulate, sometimes cut-toothed near the base, the lateral or occasionally all the (rather large purple-blue) petals bearded; spur short and thick; stigma beaked.—Dry or moist sandy places, New Eng. to Minn., and southward. Some forms pass into the last.
[++][++] Rootstocks long and filiform, extensively creeping.
[=] Flowers blue or purple.
5. V. Selkírkii, Pursh. (Great-spurred V.) Small and delicate; the filiform rootstock fibrose-rooted, no runners above ground; smooth, except the round-heart-shaped crenate leaves, which are minutely hairy on the upper surface and have a deep narrowed sinus; spur very large, thickened at the end, almost as long as the beardless pale violet petals.—Damp and shady soil, N. Maine to W. Mass., central N. Y., L. Superior (Robbins), and northward; rare.—Scapes and petioles 1–2´, the leaf ½–1¼´ long, thin; the spur 3´´ long. (Eu.)
6. V. palústris, L. (Marsh V.) Smooth; leaves round-heart-shaped and kidney-form, slightly crenate; flowers (small) pale lilac with purple streaks, nearly beardless; spur very short and obtuse.—Alpine summits of the White Mountains, N. H., and high northward. June. (Eu.)
V. odoràta, L. (Sweet Violet), cultivated in gardens, from Europe, belongs near this group, and is sparingly spontaneous in some places.
[=][=] Flowers white (small, short-spurred), mostly with brown-purple veins; lateral petals bearded or beardless. Species apparently confluent.
7. V. blánda, Willd. (Sweet White V.) Commonly glabrous; leaves round-heart-shaped or kidney-form; petals mostly beardless, the lower strongly veined.—Damp places, everywhere. Flowers faintly sweet-scented.
Var. palustrifórmis, Gray. The larger form; upper surface of the leaves sparsely and finely hairy; petals 5´´ long, oftener bearded, less distinctly veined.—Shaded mossy ground, N. Eng. to Del., and westward.
Var. renifòlia, Gray. Slightly or strongly pubescent with soft spreading hairs; leaves round-reniform; petals usually beardless. (V. renifolia, Gray.)—Maine to Mass., western N. Y., Lake Superior, etc.
8. V. primulæfòlia, L. (Primrose-leaved V.) Smooth or a little pubescent; leaves oblong or ovate, abrupt or somewhat heart-shaped at the base; petals often acute, the lateral ones usually sparingly bearded.—Damp or dry soil, N. Eng. to Fla., toward the coast.
9. V. lanceolàta, L. (Lance-leaved Violet.) Smooth; leaves lanceolate, erect, blunt, tapering into a long-margined petiole, almost entire; petals beardless.—Damp soil; common, especially eastward.
[=][=][=] Flowers yellow.
10. V. rotundifòlia, Michx. (Round-leaved Violet.) Leaves round-ovate, heart-shaped, slightly crenate; lateral petals bearded and marked with brown lines; spur very short.—Cold woods, Maine to Minn., and south along the Alleghanies.—Smoothish; leaves 1´ broad at flowering, increasing to 3 or 4´ in the summer, then lying flat on the ground, shining above.
[*][*] Leafy-stemmed; all perennial with short rootstocks.
[+] Low, at first nearly stemless; flowers yellow; stigma concave, bearded.
11. V. Nuttàllii, Pursh. Pubescent or nearly glabrous; leaves ovate to oblong-lanceolate, obtuse, entire or slightly crenate, decurrent on the petiole.—Central Kansas and westward.
[+][+] Stems erect, without root-leaves; stipules entire; spur very short; stigma beakless, pubescent.
[++] Stems naked below; flowers yellow.
12. V. pubéscens, Ait. (Downy Yellow V.) Softly pubescent (6–12´ high); leaves very broadly heart-shaped, toothed, somewhat pointed; stipules ovate or ovate-lanceolate, large; lower petals veined with purple, capsule oblong to globular, glabrous or tomentose.—Woods; common.—Var. scabriúscula, Torr. & Gray, smaller and greener, slightly pubescent (4–10´ high).—R. I. to Ky., and southwestward.
13. V. hastàta, Michx. (Halberd-leaved V.) Nearly glabrous, slender (4–10´ high); stem-leaves halberd-shaped or oblong-heart-shaped, slightly serrate, acute; stipules ovate, small.—Woods, N. Ohio (near Painesville, Miss Shattuck), mountains of Penn., and southward; rare.
[++][++] Stems more leafy and prolonged; flowers white or purplish.
14. V. Canadénsis, L. (Canada V.) Upright (1–2° high); leaves heart-shaped, pointed, serrate; stipules ovate-lanceolate, entire; petals white or whitish inside, the upper ones mostly tinged with violet beneath, the lateral bearded.—Rich woods; common northward and along the Alleghanies. May–Aug.
[+][+][+] Stems erect or spreading (at first nearly acaulescent); stipules fringe-toothed; spur oblong to cylindrical; stigma naked.
15. V. striàta, Ait. (Pale V.) Stems angular, ascending (6–10´ high); leaves heart-shaped, finely serrate, often acute; stipules oblong-lanceolate, large; spur thickish, much shorter than the cream-colored or white petals, the lateral ones bearded, the lower striped with purplish lines; stigma beaked.—Low grounds, W. New Eng. to Minn. and Mo., and southward in the mountains. April–Oct.
16. V. rostràta, Pursh. (Long-spurred V.) Stems ascending (3–6´ high); leaves roundish-heart-shaped, serrate, the upper acute; stipules lanceolate, large; spur slender (½´ long), longer than the pale violet beardless petals; style straight and slender; stigma terminal, beakless.—Shaded hillsides, N. New Eng. to Mich., and southward in the Alleghanies; rather rare. June, July.
17. V. canìna, L., var. Muhlenbérgii, Gray. (Dog V.) Low (3–8´ high), mostly glabrous; stems ascending, mostly simple, from the base at length producing creeping branches; leaves heart-shaped, or the lowest kidney-form, crenate, the uppermost slightly pointed; stipules lanceolate; spur cylindrical, half the length of the light violet petals, the lateral ones slightly bearded; stigma beaked.—Damp or wet shady places; common. May–July. (Eu.)—Var. pubérula, Watson in herb. Finely puberulent; leaves mostly ovate and acutish with a cordate base, often small; flowers small and mostly cleistogamous.—Sandy or stony shores and islands of Lakes Huron and Superior. (Robbins, Engelmann, etc.)—Var. multicaùlis, Gray. Depressed and stoloniferous; flowers mostly cleistogamous; leaves small, suborbicular to reniform.—Ky. to Fla. and Tex.
§ 2. Leaf-bearing throughout from an annual, biennial, or sometimes short-lived perennial root; the stipules large, leaf-like and lyrate-pinnatifid.
V.