ROSE FAMILY 429 



Styles lateral; ovules ascending, amphitropous. 



Undershrubs; achenes pubescent. 30. P.fruticosa. 



Herbs ; achenes glabrous. 



Petals yellow; receptacle not enlarged in fruit. 



Stems and petioles pubescent with ultimately spreading hairs; achenes with a deep dorsal groove. 



31. P. Anserina. 



Stems and petioles glabrous or nearly so; achenes without a groove. 32. P. pacifica. 



Petals red-purple, acute; receptacle somewhat enlarged and spongy in fruit. 33. P. palustris. 

 Styles basal; ovule ascending; orthotropous; perennial herbs with pinnate leaves. 

 Styles fusiform, less than twice as long as the ovaries. 



Seeds smooth, shining, light brown, oblong-ovoid, about twice as long as broad; petals cream-white. 

 Petals scarcely longer or usually shorter than the sepals. 



Stems leafy, stout, glandular-villous; flowers many in a narrow crowded cymose panicle. 



34. P. Convallana. 



Stems subscapose, the stem leaves few and reduced; flowers few in open cymes. 



35. P. Hansemi. 



Petals well exceeding the sepals. 



Sepals lanceolate or ovate-lanceolate; bractlets lanceolate to linear. 36. P. ashlandica. 



Sepals broadly ovate; bractlets elliptic to oval. 37. P. pumila. 



Seeds finely reticulate or veined, dull dark brown, obliquely and broadly ovoid, often nearly as broad as 

 long; stems leafy, glandular-villous. 

 Petals not reflexed in anthesis; seeds reticulate, sometimes obscurely so. 



Petals yellow; sepals mainly ovate-lanceolate-acute. 38. P. glandulosa. 



Petals cream-white; sepals rounded or obtuse at apex. 39. P. W rangelliana. 



Petals reflexed in anthesis, yellow; seeds conspicuously veined. 40. P. reflexa. 



Styles filiform or nearly so, more than twice the length of the ovaries. 41. P. rhomboidea. 



1. Potentilla procumbens Sibth. Wood Cinquefoil. Fig. 2415. 



Tormentilla reptans L, Sp. PI. 500. 1753. Not P. reptans L. 

 Potentilla procumbens Sibth. Fl. Oxon. 162. 1794. 

 Potentilla nemoralis Nestl. Mon. Pot. 65. 1816. 



Stems slender, prostrate and often rooting at the nodes, strigose or glabrate. Stipules oblong- 

 lanceolate, usually entire ; leaves digitally 5-foliolate, the petioles 3-10 cm. long ; leaflets cuneate 

 to oblanceolate, obtuse or rounded at the apex, 1-3 cm. long, crenate or dentate appressed- 

 pubescent on both surfaces or glabrate in age ; bractlets ovate or elliptical, 5-10 mm. long, usually 

 well exceeding the ovate sepals ; petals 4, obcordate, 6-10 mm. long. 



Widely distributed over Europe, naturalized in Labrador, Nova Scotia, California, and Oregon. April-July. 



2. Potentilla paradoxa Nutt. Bushy Cinquefoil. Fig. 2416. 



Potentilla paradoxa Nutt. ex Torr. & Gray, Fl. N. Amer. 1 : 437. 1840. 



Annual or biennial with decumbent or erect, simple or bushy stems, sparsely pubescent 3-6 

 dm high. Stipules ovate-lanceolate, usually entire, ciliate; leaves petioled, pinnately 7-11- 

 foliolate ; leaflets obovate or oblong, 1-2 cm. long, deeply crenate, in age glabrous ; flowers in 

 leafy-bracted cymes ; hypanthium sparingly hairy, 7-9 mm. broad ; bractlets about equaling the 

 oblong-ovate sepals, 3-4 mm. long; petals obovate-cuneate, slightly exceeding the sepals; achenes 

 with a thick corky swelling on the inner side. 



In sandy bottom land, Transition Zone; Ontario and New York to New Mexico and eastern Washington. 

 Type locality : banks of the Ohio River. May-July. 



3. Potentilla rivalis Nutt. River Cinquefoil. Fig. 2417. 



Potentilla rivalis Nutt. ex Torr. & Gray, Fl. N. Amer. 1 : 437. 1840. 

 Tridophyllum rivale Greene, Leaflets Bot. Obs. 1 : 189. 1905. 



Stems erect, simple below, branched above, 3-6 dm. high, finely villous-hirsute and somewhat 

 viscid, leafy. Lower leaves pinnately 5-foliolate, and the upper leaflet often ternate; leaflets Z-5 

 cm long, obovate, with coarse ovate teeth ; cyme with ascending branches, leafy ; flowers short- 

 pedicelled ; hypanthium hirsute, about 5 mm. broad ; bractlets oblong, about 3 mm. long ; sepals 

 ovate, acute, 3-4 mm. long ; petals yellow, cuneate, much shorter than the sepals ; stamens about 

 10; achenes smooth. 



Moist bottom lands, Transition and Sonoran Zones; British Columbia to southern California, east to Sas- 

 katchewan and Mexico. Type locality: Lewis River, collected by Nuttall. April-Sept. 



4. Potentilla millegrana Engelm. Diffuse Cinquefoil. Fig. 2418. 



Potentilla millegrana Engelm. ex Lehm. Ind. Sem. Hamb. 1849: Add. 12. 1849. 

 Potentilla rivalis var. millegrana S. Wats. Proc. Amer. Acad. 8: 553. 1873. 

 Potentilla leucocarpa Rydb. in Britt. & Brown, 111. Fl. 2: 212. 1897. 



Stems usually diffusely branched, weak and decumbent, 15-30 cm. high, soft villous-pubescent 

 or glabrate Leaves 3-foliolate, more or less pubescent; leaflets oblong-cuneate, 1-6 cm. long, 

 thin, deeply serrate; cyme spreading, its leaves bractlike; hypanthium soft-pubescent, 4-5 mm. 

 broad ; bractlets and sepals oblong-ovate, 3-4 mm. long ; petals pale yellow, about half the length 

 of the sepals ; stamens usually 10 ; achenes smooth, light colored. 



Sandy bottom lands, mainly Transition Zone; Washington and Manitoba to California, Illinois, and New 

 Mexico. Type locality: St. Louis, Missouri. April-Oct. 



