ROSE FAMILY 421 



long, longer than the linear bractlets ; petals obcordate, unguiculate, exceeding the sepals ; pistils 

 3-6 ; styles glandless, long-persistent. 



Barren slopes, Transition and Canadian Zones; Coast Ranges of southwestern Oregon. Type locality: sum- 

 mit of the Coast Range, Curry County, Oregon. May-Aug. 



16. Horkelia daucifolia (Greene) Rydb. Carrot-leaved Horkelia. Fig. 2394. 



Potentilla daucifolia Greene, Pittonia 1 : 160. 1888. 



Potentilla congcsta var. lobata t.emmon, Bull. Torrey Club 16: 211. 1889. 



Horkelia daucifolia Rydb. Bull. Torrey Club 25: 55. 1898. 



Horkelia caruifolia Rydb. ex Howell, El. N.W. Amer. 1 : 181. 1898. 



Stems mostly simple from a short caudex, about 3 dm. high, glandular-pubescent throughout 

 and pilose with long fine hairs. Leaflets of basal leaves 8-12 pairs, 1-3 cm. long, divided to near 

 the base into linear segments, silky-pilose ; stipules of basal leaves twice dissected into narrowly 

 linear segments; hypanthium 4-5 mm. broad, silky-pilose; sepals 4-5 mm. long, triangular- 

 lanceolate, a little longer than the linear bractlets. 



Dry, barren ground, Arid Transition Zone; Rogue River Valley, Oregon, to Shasta Valley, California. Type 

 locality: Klamath and Shasta Valleys, California. May-Aug. 



17. Horkelia congesta Dougl. Dense-flowered Horkelia. Fig. 2395. 



Horkelia congesta Dougl. ex Hook. Bot. Mag. 56: pi. 2880. 1829. 

 Horkelia hirsuta Lindl. Bot. Reg. 23: under pi. 1997. 1837. 

 Sibbaldia congesta D. Dietr. Syn. PI. 2: 1020. 1840. 

 Potentilla congesta Baillon, Hist. PI. 1: 369. 1867-9. 



Stems slender from a short caudex, 3-4 dm. high, hirsute toward the base. Leaflets of basal 

 leaves 4-5 pairs, linear-oblong, 10-15 mm. long, deeply 2-3-toothed at apex, silky-villous, pale 

 green and thin; stipules filiform-divided; hypanthium sparingly silky-villous without, glabrous 

 within, 5 mm. broad; sepals ovate-acuminate, 2-3 mm. long, exceeding the linear-filiform bract- 

 lets ; petals broadly obovate, cream-colored, nearly 4 mm. long ; filaments all lanceolate. 



Dry open places, Transition Zones; Willamette Valley south to Josephine County, Oregon. Type locality: 

 Umpqua River, Oregon. May-July. 



18. Horkelia tridentata Torr. Three-toothed Horkelia. Fig. 2396. 



Horkelia tridentata Torr. Pacif. R. Rep. 4: 84. 1857. 



Horkelia Tilingii Regel, Act. Hort. Petrop. 1: 153. 1871. 



Potentilla Tilingii Greene, Pittonia 1: 105. 1887. 



Horkelia flavescens Rydb. Mem. Dept. Bot. Columbia Univ. 2: 138. 1898. 



Horkelia integrifolia Rydb. N. Amer. Fl. 22: 279. 1908. 



Potentilla congesta var. Tilingii Jepson, Man. Fl. PI. Calif. 496. 1925. 



Stems several, ascending or decumbent from a short cespitose caudex and taproot, 2-4 dm. 

 high. Leaflets of basal leaves 3-4 pairs, cuneate to oblong-obovate, generally 3-toothed at the 

 apex, 10-15 mm. long, white silky-pubescent; cyme often branched with subcapitate terminal 

 clusters of flowers ; hypanthium silky-villous, 3-4 mm. broad ; sepals broadly ovate, 1-2 mm. 

 long, exceeding the linear bractlets ; petals oblanceolate ; filaments all linear-lanceolate. 



Open places in yellow pine forests, Arid Transition Zone; Siskiyou Mountains, southern Oregon to the 

 Coast Ranges, northern Lake County, and to the southern Sierra Nevada, California. Type locality: "wet 

 ravines, Dufneld's Ranch, Sierra Nevada, Tuolumne County, California." May-July. 



19. Horkelia purpurascens S. Wats. Purple Horkelia. Fig. 2397. 



Horkelia purpurascens S. Wats. Proc. Amer. Acad. 11: 148. 1876. 



Potentilla purpurascens Greene, Pittonia 1: 105. 1887. 



Horkeliclla purpurascens Rydb. N. Amer. Fl. 22: 282. 1908. 



Potentilla purpurascens var. pinetorum Coville, Proc. Biol. Soc. Wash. 7: 77'. 1892. 



Ivesia purpurascens Keck, Lloydia 1 : 132. 1938. 



Stems erect from a short erect caudex, more or less pubescent and glandular. Basal leaves 

 numerous, 8-15 cm. long; leaflets 15-20 pairs, crowded, 2-4 mm. long, divided to near the base 

 into 2-4 oval lobes, more or less hirsute ; cyme narrow with erect branches ; hypanthium hirsute, 

 cupulate, 4-5 mm. broad ; sepals lanceolate, twice the length of the linear bractlets ; petals strap- 

 shaped, emarginate, slightly exceeding the sepals, white, often tinged with purple. 



Dry soils, on the margins of mountain meadows, Transition and Canadian Zones; southern Sierra Nevada, 

 California. Type locality j headwaters of Kern River, California. June— Aug. 



Horkelia purpurascens subsp. Congdonis (Rydb.) Abrams (Horkelia Congdonis Rydb. Bull. Torrey Club 

 26: 543. 1899.) Distinguished mainly from the typical species by the glandular stems, and the obtuse petals. 

 Mainly eastern slopes of the southern Sierra Nevada, California. Type locality: Casa Diablo, Mono County, 

 California. 



11. IVESIA Torr. & Gray, Pacif. R. Rep. 6 3 :72. 1857. 



Perennials with thick erect rootstocks. Leaves mostly basal and numerous, pinnate, 

 the leaflets numerous, small, more or less crowded and imbricate. Flowers 5-merous, in 

 open or dense cymes. Hypanthium campanulate or commonly saucer-shaped, bearing 

 bractlets alternate with the 5 sepals. Petals white or yellow, oblanceolate and clawed or 

 nearly orbicular and clawless. Stamens 5 or 20 (rarely 10 or 15), inserted in the throat 

 of the hypanthium; filaments filiform, except in /. argyrocoma. Pistils 1-15, surrounded 



