800 VIOLACEAE 



FAMILY 11. VIOLACEAE DC. 1 VIOLET FAMILY. 



Herbs, or in tropical regions occasionally shrubs or trees, with simple alter- 

 nate or basal stipulate leaves, and perfect usually irregular solitary or clustered 

 flowers. Sepals and petals 5, the latter hypogynous, imbricated in the bud, the 

 lowermost often spurred. Stamens 5, the anthers erect, syngenesious or con- 

 nivent. Gynoecium 3-carpellary. Ovary 1-celled, enclosing numerous ovules 

 on the 3 parietal placentae and becoming in fruit a loculicidal capsule. Seeds 

 anatropous. 



Sepals auriculate at base. 1. VIOLA. 

 Sepals not auriculate at base. 



Anthers syngenesious : upper and lateral petals nearly equal. 2. CUBELIUM. 



Anthers connivent : upper and lateral petals markedly unequal. 3. CALCEOLARIA. 



1. VIOLA L. 



Leafy-stemmed or acaulesceiit and scapose herbs, with usually prominent stipules and 

 solitary axillary flowers, often succeeded in the late season by apetalous or cleistogamous 

 freely fruit-producing flowers. Petals spreading, the lowermost saccate or spurred. 

 Stamens 5, the lowermost two appendaged. Capsule 3-valved, elastically dehiscent. 



I. Acaulescent : flowers scapose. 

 Plants not stoloniferous. 



Leaf-blades lobed or parted (except in V. palmetto, asarifolia). 



Cleistogamous flowers wanting : petals beardless. FED ATA E. 1. V. pcdata. 



Cleistogamous flowers present : petals bearded. HETEROPHYLLAE. 

 Plants always more or less pubescent. 



Leaf-blade with the central lobe the largest. 2. V. palmata. 



Leaf-blade with the two outer lobes the largest. 3. V. falcata. 



Plants comparatively glabrous, or with slight traces of pubescence. 

 Lobes extending to the center of the leaf-blade. 



Scapes surpassing the leaves : blades of the latter pedately 5-7- 



lobed. 4. V. septemloba. 



Scapes not surpassing the leaves : blades variously 3-lobed. 5. V. vicinatts. 



Lobes very shallow. 



Leaf-blades subsinuately toothed or parted. 6. V. subsinuata. 



Leaf-blad es somewhat palmately 5-lobed. 7. V. hdcrophylla. 



Leaf-blades merely crenate or dentate, cordate-ovate in outline, none lobed. 



COMMUNES. 



Plants small (less than 1 dm. high). 

 Leaf-blades reniform-orbicular. 



Corolla reddish purple : spur small. 8. V. villosa. 



Corolla blue : spur large and broadly saccate. 9. V. Carolina. 



Leaf-blades deltoid-triangular. 



Petioles slightly exceeding the blades. 10. V. Langloisii. 



Petioles usually twice as long as the blades. 11. V. Alabamensis. 



Plants large (more than 1 dm. high). 



Leaves not cucullate ; blades attenuate at apex. 12. V. affinis. 



Leaves cucullate ; blades abruptly acute. 



Corolla deep purple : scapes exceeding the leaves. 13. V. papilionac<a. 



Corolla pale purple : scapes not exceeding the leaves. 14. V. Mieeouriensit, 



Leaf-blades crenate, dentate, or somewhat incised at the base, ovate-sagit- 

 tate or ovate-lanceolate. SAGITTATAE. 



Plants distinctly villous 15. V. Jimbnatula. 



Plants glabrate or only ciliate. 



Leaf-blades sagittate-lanceolate. 16. V. sagittata. 



Leaf-blades broader. 



Leaf-blades oblong-elliptical. 17. V. amorphophytta. 



Leaf-blades deltoid-triangular. 18. V. emarginata. 



Plants stoloniferous. 



Introduced species : corolla purple. ODORATAE. 19. V. odorata. 



Native species : corolla not purple. 



Corolla yellow. ORBICULATAE. 20. V. rotundifolia. 



Corolla white. BLANDAE. 



Leaf-blades from broadly ovate to orbicular : cleistogenes deflexed. 



Upper and lateral petals twice as long as broad : petioles not spotted. 21. V. blanda. 

 Upper and lateral petals thrice as long as broad : petioles red- 

 spotted. 22. V. LeOmteana. 

 Leaf-blades from narrowly oval to linear : cleistogenes erect. 



Leaf-blades oval or ovate-oblong. 23. V. primulaefoha. 



Leaf-blades from lanceolate to linear-lanceolate. 



Corolla 2 cm. broad. 24. V. dcnticulosa. 



Corolla less than 1.5 cm. broad. 



Blade and petiole distinct, of nearly equal length. 25. V. lanccolata. 



Blade and petiole coalescent. 26. V. vittata. 



II. Caulescent, leafy-stemmed : flowers axillary. 

 A. Corolla yellow. HASTATAE. 



a. Rootstock tuberous, white and succulent. 27. V. hastata. 



1 Contributed by Mr. Charles Louis Pollard. 



