546 



VIOLACEAE. Vol. II. 



characters more or less intermediate to those O- the parent species, and show marked vege- 

 tative vigor, but impaired fertility; their offspring are often much unlit:e the mother plant 

 and unlike each other, reverting variously to the characters of the two original species. 



Some 200 species, widely distributed. Besides the following, about 35 others occur in the 

 southern and western parts of North America. Viola villosa Walt. {V. Carolina Greene), of the 

 Southern States, may be looked for in southeastern Virginia. Type species : Viola odorata L. 

 * Stemless, the leaves and scapes directly from a eootstock or from runners. 

 t Flowers without marked fragrance ; indigenous. 

 % Petals violet or white. 

 Cleistogamous flowers wanting; petals all beardless. i. V.pedata. 



Cleistogamous flowers present. 



A. Rootstock thick, often stout, without stolons ; lateral petals bearded. 



1. Cleistogamous flowers ovoid on short prostrate peduncles ; their capsules mostly purplish. 

 Leaves (except rarely the earliest) palmately 5-11-lobed or -parted. 



Plants villous-pubescent ; seeds larown. 2. V. palmate. 



Plants nearly or quite glabrous ; seeds buff. 3. V. Stoneana. 



Early and late leaves uncut ; others 3-7-lobed or -parted, villous-pubescent. 4. V. triloba. 

 Leaves all uncut; blades ovate to reniform, cordate, crenate-serrate. 

 Plants nearly or quite glabrous. 



Petals violet-purple ; seeds brown. 



Petioles smooth ; plants of moist soil. 5. V, papilionacea. 



Petioles glandular roughened ; plants of dry soih 6. V. latiuscula. 



Petals pale violet, or nearly white ; seeds buff. 7. V. missouriensis. 



Leaves villous, especially beneath and on petioles ; seeds dark-brown. 8. V. sororia. 

 Leaves hirsutulous above, otherwise glabrous ; seeds buff. 9. V. hirsutula. 



2. Qeistogamous flowers ovoid, on ascending peduncles soon elongate, their capsules purplish ; 



leaves cordate, none cut. 



Leaves pubescent beneath and on petioles. 



Sepals and their auricles ciliolate ; blades broadly ovate, cordate. 10. V. sepfenfrionalis. 



Sepals and auricles not ciliate ; blades at flowering time narrowly ovate. 11. V. novae-angliae. 



Leaves glabrous beneath and on petioles. 12. V, affinis. 



3. Cleistogamous flowers on erect peduncles, their capsules green. 

 Leaves ovate to reniform, cordate, glabrous, uniformly crenate-serrate. 



Cleistogamous flowers ovoid ; spurred petal villous. 



Mature leaves rounded at apex or bluntly pointed ; sepals obtuse. 13, V, nephrophylla. 

 Mature leaves abruptly acuminate; sepals acute. 14. V.retusa. 



Cleistogamous flowers long and slender, spurred petal glabrous. 15. V. cucullata. 



Leaves lobed, or the margins sharply incised or toothed toward the subcordate or truncate base. 

 Spurred petal glabrous, lateral with clavate beard ; leaves lobed. 16. V.viarum, 



Spurred petal villous, lateral with capillary beard. 



Blades of mature leaves ovate-oblong, ciliate, finely pubescent. 17. V.fimbriatula. 



Blades of mature leaves lanceolate, usually glabrous ; petioles long. 18. V, sagittate. 

 Blades of mature leaves broadly ovat.e or deltoid. 



Margin coarsely toothed near base; blades sometimes lobed. 19. V. emarginata. 



Margin sharply toothed toward base or pectinately incised. 20. F. pectinata. 



Blades of mature leaves primarily 3-lobed 01* 3-parted, segments variously cleft. 



Segments 2-3-cleft into linear or oblanceolate lobes; eastern. 21. V. Brittoniana. 

 Segments 3-cleft, the subdivisions often 2-4-lobed ; western. 22. V. pedatifida. 



Middle segment un'-ut, the outer usually 2-4-clef t ; southern. 23. V. septemloba. 



B. Rootstocks slender (thicker and scaly zvith age) ; plants usually from stolons. 

 Petals lilac or pale violet. 



Leaves minutely hairy on the upper surface ; spur large, 3" long. 24. F. Selkirkii. 

 Leaves glabrous throughout ; spur short, i" long. 25. V . palustris. 



Petals white, with dark purple lines on the three lower. 



Cleistogamous capsules ovoid, usually purpHsh ; woodland plants. 



Leaves reniform, lateral petals beardless ; stolons short. 26. V. renifolia. 



Leaves broadly ovate, acute, lateral petals bearded ; seeds obtuse at base. 



27. V, incognita. 

 Leaves ovate, acute or acuminate ; lateral petals beardless, seeds acute at base. 



28. F. blanda. 

 Cleistogamous capsules ellipsoid, always green, peduncles erect ; bogs and wet meadows. 



Leaves broadly ovate or orbicular, cordate, obtuse. 29. V. pollens. 



Leaves oblong to ovate; base slightly cordate to tapering. 30. V. primulifolia. 



Leaves lanceolate or elliptical. 31. F. lanceolata. 



tt Petals bright yellow. 32. V.rotundifolia. 



tt Flowers very fragrant ; introduced. 33. F. odorata. 



** Leafy stemmed; the flowers axillary. 



t Style capitate, beakless, bearded near the summit; spur short; stipules nearly entire, 

 soon scarious. 

 Stems at first short, flowers and leaves from near the base ; later elongating. 34. V.Nuttallii. 

 Stems not leafly below; peduncles from axils of upper leaves. 

 tPetals yellow. 

 Rootstock short, woody, brown, bearing coarse fibrous roots. 35. V. hastata. 



Rootstock long, brittle, whitish, bearing crisp capillary roots. 



Sparingly pubescent ; root-leaves usually 1-3 36. V. eriocarpa. 



Markedly pubescent ; root-leaves usually wanting. 37. V.pubescens. 



ttlnner face of petals white with yellow base, outer face usually violet. 

 Root-leaves and lower stem-leaves reniform, densely hirsutulous beneath. 38. F. rugulosa. 



Root-leaves and lower stem-leaves broadly ovate, acuminate, subglabrous. 39. F. canadensis. 



