Source: https://chestofbooks.com/flora-plants/Botany-Flora-USA-Canada/Order-XVI-Violaceae-Violets.html
Timestamp: 2019-04-20 00:11:41+00:00

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Genera 15, species 800, mostly inhabitants of the Northern temperate zone. The roots of almost all the Violaceae possess emetic properties, and some are valued in medicine. The Ipecac of the shop is partly the product of certain Brazilian species of Ionidium. Several species of the violet are cultivated for the beauty of their flowers.
i. VIOLA, L. Violet. Pansey. (From the Latin.) Sepals 5, unequal, auricular at base; petals 5, irregular, the broadest spurred at base, the 2 lateral equal, opposite; stamens approximate, anthers connate, two of them with appendages at the back; capsule 1-celled, 3-valved, seeds attached to the middle of the valves.- Low, herbaceous plants. Ped. angular, solitary, 1-flowered, recurved at the summit so as to bear the flowers in a resupinate position. Joints of the rhizome often bearing apetalous flowers.
1 V. rotundifolia Mx. Fig. 305. Lvs. orbicular-ovate, cordate, slightly serrate, nearly smooth, with the sinus closed; petiole pubescent; cal. obtuse. - A small, early violet, found in woods, N. Eng. to Tenn. Lvs. varying from ovate to reniform, mostly round, with a narrow sinus at base. Veins and petioles pubescent. Ped. as long as the leaves, sub-4-sided, bracted in the middle. Petals yellow, marked at base with brown lines. Fls. small. Mar., May.
2 V. lanceolata L. Lvs. smooth, lanceolate, tapering at base into the long petiole obtusish, suberenato. - Found in wet meadows, Can. and U. S. Rhizome creeping. Lvs. varying from lanceolate to linear, and, with the stalk 3 - 5' long. Petioles half-round. Ped. sub-4-sided. Petals white, greenish at base, upper and lateral ones marked with blue lines, generally beardless. Fls. small, those from the lower nodes of the rhizome apetalous. Mar. (S) - May.
3 V. primulaefolia L. Lvs. lance-ovate, abruptly contracted at base and decur-rent on the petiole; petals nearly equal, beardless. - Found in damp soils, Mass. to Ga. and Tenn. Rhizome creeping. Lvs. sometimes subcordate, rather obtuse, crenate, pubescent or nearly smooth. Petals obovate, flat, marked with purple lines at base, generally beardless and obtuse. Fls. small, white, on sub-4-sided stalks. May, in N. Eng.
4 V. blanda Willd. Lvs. cordate, roundish, slightly pubescent; petiole pubescent; petals beardless. - Found in meadows, Can. to Penn. Rhizome slender and creeping. Lvs. close to the earth and sometimes with a rounded sinus so as to appear reniform. Petioles half round. Peduncles sub-4-sided, longer than the leaves. Petals white, greenish at base, upper and lateral ones marked with a few blue lines. Fls. small, fragrant. May (V. clandestina Ph. V. amoena Le Conte).
5 V. palustris L. Lvs. reniform-cordate; stip. broadly ovate, acuminate; stig. margined; sep. ovate, obtuse, spur very short; caps. oblong-triangular. - Summits of the White Mts. About 3' high, pubescent Lvs. crenate, 1' by 3/4. Fls. small, pale blue on peduncles longer than the leaves and bibracteate near the middle. Rhizome creeping, scaly. Jn.
6 V. Selkirkii Goldie. Selkirk's Violet. Lvs. orbicular-cordate, crenately serrate, the sinus deep and nearly closed; spur nearly as long as the petals, thick very obtuse. - Grows on woody bills and mountains, Mass., N. Y., Can., rare. A small, stemless violet 2' high, with small, pale blue fls. conspicuously spurred. Lvs. rather numerous and longer than the peduncles. Petals beardless, the upper one striate with deep blue. May.
7 V. pedata L. Rt. premorse; lvs. pedately 5 - 9-parted, segments linear-lanceolate, entire; stig. large, obtusely truncate, scarcely beaked; spur short, obtuse.- A smooth, beautiful, large-flowered violet, in hilly woods, Can. to Ill. and Fla. Rhizome fleshy, ending abruptly as if cut or bitten off. Lvs. thick, 2-ternately divided into about 7 obtuse, narrow segments. Petioles with long, ciliate stipules at base. Ped. sub-4-angled, much longer than the leaves. Petals pale blue, white at base, all of them beardless and entire. Apr., May.
β. The two upper petals deep violet colored, the others light-blue with much yellow at their bases, as in the garden pansey. Plants smaller, with large flowers. - In Mt Hope Cemetery, Macon, Ga.
8 V. delphinifolia Nutt. Lvs. pedately 7 - 9-parted, with linear, 2 - 3-cleft segments all similar; stig. thick, distinctly beaked. - Prairies and bottoms, Ill., Iowa, Mo. Lvs. often finely divided with many dissected segments, pubescent along the edge, prominently veined beneath. Stip. acuminate, subentire. Ped. a little longer than the leaves. Fls. rather smaller than in the last, of a rich blue; lateral petals bearded. Mar., Apr.

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