VIOLACEAE (VIOLET FAMILY) 321 



Plants larger, erect or suberect. 



Leaves, petioles, and peduncles green and glabrate . 6. V. erectifolia. 

 Leaves, petioles, and peduncles somewhat white-hir- 

 sute 7. V. linguaefolia. 



Flowers not yellow. 



Acaulescent; flowers scapose. 



Flowers white 8. V. blanda. 



Flowers blue, lilac, or violet. 



Stoloniferous . . . . . . . 9. V. palustris. 



Producing no stolons. 



All the leaves obtuse ....... 10. V. nephrophylla. 



The later leaves trigonous-acute . . . . 11. V. retusa. 



Caulescent; flowers axillary. 



Stipules entire, mostly scarious . . . . . 12. V. canadensis. 



Stipules fimbriate or incised. 

 Leaves glabrous. 



Dwarf, alpine plants 13. V. bellidifolia. 



Larger, plants of the mountain valleys . . .14. V. adunca. 

 Leaves puberulent. 



Stipules more or less fimbriate. 



Petioles glabrous ....... 15. V. odontophora. 



Petioles retrorse-pubescent ..... 16. V. montanensis. 



Stipules more or less laciniate 17. V. subvestita. 



Annual or short-lived perennial; stipules leaf-like .... 18. V. Rafinesquii. 



1. Viola pedatifida Don, Card. Diet. 1: 320. 1831. Acaulescent, the 

 leaves and scapes from short, thick, vertical rootstocks: leaves pedately dis- 

 sected or flabellately palmate or ternate, the segments ternately or pinnately 

 divided into broadly linear segments, minutely pubescent or glabrate: scapes 

 and leaves subequal, 1-2 dm. high: flowers blue or shading toward white; the 

 lateral petals bearded: capsules about 10 mm. long, those from the abundant 

 cleistogamous flowers short-peduncled. V. delphinifolia. (V. biternata 

 Greene, PI. Baker. 3: 12. 1901; V. Sheltonii Rydb. Fl. Col., not Torr.) From 

 the Rocky Mountains to the Mississippi. 



2. Viola biflora L. Sp. PI. 936. 1753. Stems 2 or more from a short vertical 

 rootstock, 1-2 dm. long, weak, ascending, about 2-leaved, and 1- or 2-flowered 

 at summit: leaves nearly glabrous, round-reniform, with narrow sinus, 2-3 cm. 

 broad; stipules green and entire: flowers small: sepals linear-oblong: petals 

 yellow with dark purple-brown striae, spur short. -Colorado; seemingly the 

 same as the old-world form. 



3. Viola atriplicifolia Greene, Pitt. 3: 38. 1896. Dwarf, the whole stem 

 including the petioles and longer peduncles about 5 cm. high: herbage cin- 

 ereously puberulent, leaf-margins not ciliate; petioles 3-4 cm. long; the lamina 

 mostly less than 12 mm. long, that of the lowest leaf broader than long, all 

 truncate at base and angularly but not deeply 5-7-lobed, or the uppermost 

 3-lobed and hastate: flowers small, yellow, the upper pair of petals red-purple 

 externally. Dry hills, Yellowstone National Park. 



3a. Viola atriplicifolia Thorii A. Nels. Nearly glabrous and the leaves 

 merely coarsely dentate. (V . Thorii A. Nels. Bull. Torr. Bot. Club 27: 193. 

 1900.) Mountains of Yellowstone Park, Montana, and probably westward. 



4. Viola Nuttallii Pursh, Fl. Am. Sept. 1: 174. 1814. Roots semifleshy, 

 often branched or fascicled: stems several, short, spreading: leaves oblong- 

 lanceolate to nearly linear, 3-6 cm. long, tapering to the margined petiole 

 which usually exceeds the blade, more or less puberulent, entire or obscurely 

 repand-denticulate: peduncles mostly shorter than the leaves: sepals lanceo- 

 late, acuminate: petals yellow, 8-12 mm. long, glabrous or slightly bearded: 

 stigma bearded: capsule subglobose. From the Rocky Mountain plains into 

 Nebraska and Kansas. 



5. Viola vallicola A. Nels. Bull. Torr. Bot. Club 26: 128. 1899. Low, cau- 

 lescent, glabrous or puberulent, from a short rootstock with fascicled fleshy 

 roots: stems few, short or at length 10-15 cm. long: leaves entire, ovate, 

 mostly obtuse, the base rounded or (in the broadest) subcordate, 2-5 cm. 

 long, on petioles as long or longer: peduncles mostly shorter than the leaves: 

 sepals lanceolate: petals yellow, streaked with purple, 10-14 mm. long: cap- 

 sules oval with many large ovoid seeds. (V. physalodes Greene, PL Baker. 

 3: 12. 1901.) Moist mountain valleys; Dakota and Colorado. 



ROCKY MT. BOT. 21 



