ROSE FAMILY 427 



puberulent; sepals triangular-lanceolate, 2.5 mm. long, longer than the narrowly linear bractlets; 

 petals yellow, spatulate, slightly exceeding the sepals ; stamens 5. 



Alpine slopes, Hudsonian and Arctic Zones; Wenatchee Mountains, Washington; also the Coeur d'Alenes, 

 Idaho. Type locality: "Yakima Region, Washington." July-Aug. 



14. Ivesia Gordonii (Hook.) Torr. & Gray. Gordon's Ivesia. Fig. 2411. 



Horkelia Gordonii Hook. Kew Journ. Bot. 5: 341. 1853. 



Ivesia Gordonii Torr. & Gray in Newb. Pacif. R. Rep. 6 s : 72. 1857. 



Potentilla Gordonii Greene, Pittonia 1 : 106. 1887. 



Ivesia alpicola Rydb. Howell, Fl. N.W. Amer. 1 : 182. 1898. 



Horkelia Gordonii var. alpicola Rydb. Mem. Dept. Bot. Columbia Univ. 2: 152. 1898. 



Stems subscapose from a short cespitose caudex, minutely glandular-puberulent, 1-2 dm. 

 high Basal leaves numerous, puberulent; leaflets 10-20 crowded pairs, 5-12 mm. long, divided 

 into 3-5 broadly oblong segments ; cyme capitate ; hypanthium 4-5 mm. broad, villous-pubescent 

 and glandular ; sepals ovate, 5 mm. long, twice the length of the linear bractlets ; petals yellow, 

 shorter than the sepals ; stamens 5 ; pistils 1-6. 



Alpine slopes, Arctic-Alpine Zone; southern Washington to northern California, Montana, and Colorado. 

 Type locality : upper Platte River. July-Aug. 



15. Ivesia lycopodioides A. Gray. Club-moss Ivesia. Fig. 2412. 



Ivesia lycopodioides A. Gray, Proc. Amer. Acad. 6: 530. 1865. 

 Ivesia Gordonii var. lycopodioides S. Wats. Bot. Calf. 1: 183. 1876. 

 Potentilla Gordonii var. lycopodioides Greene, Pittonia 1: 106. 1887. 

 Horkelia lycopodioides Rydb. Mem. Dept. Bot. Columbia Univ. 2: 151. 1898. 



Stems scapose from a densely cespitose caudex, glabrous, less than 5 cm. high. Basal leaves 

 crowded, about 3 cm. long, glabrous ; leaflets numerous, more or less imbricate, 1-2 mm. long ; 

 cyme few-flowered; hypanthium 3 mm. broad, glabrous or puberulent, the lobes 2 mm. long, 

 about a third longer than the oblong bractlets ; petals oblong-oblanceolate, about equaling the 

 sepals, pilose ; stamens 5 ; filaments and styles 1 mm. long. 



Summits of high mountain peaks, Arctic- Alpine Zone; central Sierra Nevada, California. Type locality: 

 Mount Dana, 11,000-12,000 feet altitude. July-Aug. 



Ivesia lycopodioides subsp. scandularis (Rydb.) Keck, Lloydia 1: IIS. 1938. (Ivesia scandularis Rydb. 

 N Amer Fl 22: 228. 1908.) Alpine dwarf like the typical species, but leaves densely puberulent and less 

 viscid and the leaflets villous-ciliate. Alpine meadows, Boreal Zones; White Mountains, Mono County, and 

 Sierra Nevada, Inyo County, California. Type locality: White Mountains, elevation 12,000 feet, California. 



Ivesia lycopodioides subsp. megalopetala (Rydb.) Keck, Lloydia 1: 119. 1938. (Ivesia megalopetala 

 Rydb N Amer Fl. 22: 289. 1908.) Stems ascending, 10-25 cm. long; herbage glabrate, sparsely glandular 

 with sessile glands. Leaves approximate but not imbricate, the segments linear to spatulate, thinner; flowers 

 about 10 mm broad; filaments and styles 2 mm. long. Subalpine meadows, Boreal Zone; Sierra Nevada from 

 Tuolumne County to southeastern Tulare County, California. Type locality: Mount Dana, California. 



16. Ivesia Shockleyi S. Wats. Shockley's Ivesia. Fig. 2413. 



Ivesia Shockleyi S. Wats. Proc. Amer. Acad. 23: 263. 1888. 



Horkelia Shockleyi Rydb. Mem. Dept. Bot. Columbia Univ. 2: 153. 1898. 



Stems subscapose from a densely cespitose caudex, glandular-pubescent, 2-10 cm. high. Basal 

 leaves numerous, 2-6 cm. long; leaflets 8-12 pairs, crowded, 2-4 mm. long, cleft to the base 

 into several obovate thick segments, densely glandular-pubescent and with a few scattered cilia, 

 bristle-tipped; cyme open; hypanthium 3 mm. broad, glandular-pubescent; sepals ovate, twice 

 the length of the ovate bractlets; petals about equaling the sepals; stamens 5. 



Rocky alpine slopes, Boreal Zones; Sierra Nevada and White Mountains from Placer County to Inyo County, 

 California, and western Nevada. Type locality: summit of Silver Peak, Alpine County, California. July-Sept. 



17. Ivesia Baileyi S. Wats. Bailey's Ivesia. Fig. 2414. 



Ivesia Baileyi S. Wats. Bot. King Expl. 90. 1871. 



Potentilla Baileyi Greene, Pittonia 1: 105. 1887. 



Horkelia Baileyi Rydb. Mem. Dept. Bot. Columbia Univ. 2: 154. 1898. 



Stems several, from a cespitose caudex, decumbent or ascending, 1-3 dm. long, finely pubes- 

 cent or glabrate. Basal leaves many, 5-15 cm. long; leaflets 4-6 rather distinct pairs, pubescent 

 or glabrate, 5-10 mm. long, broadly obovate, deeply incised into broadly obovate segments; stem 

 leaves with 2-3 pairs of leaflets; inflorescence leafy-bracted, open and truly cymose; pedicels 

 very slender, often 15-20 mm. long; hypanthium saucer-shaped, 4-5 mm. broad, glandular- 

 pubescent, distinctly 5-angled in fruit ; sepals ovate, 2 mm. long, about twice the length of the 

 linear-oblong bractlets ; petals yellow, spatulate, shorter than the sepals ; stamens 5. 



Mountain cliffs, Boreal Zones; southeastern Oregon, southern Idaho, and adjacent Nevada. Type locality: 

 Wright's Canon, West Humboldt Mountains, Nevada. July-Aug. 



12. POTENTILLA L. Sp. PI. 495. 1753. 



Perennial or rarely annual herbs with digitately or pinnately compound leaves and 

 cymose or solitary, yellow, perfect flowers. Hypanthium persistent, concave or hemi- 

 spherical, 5-bracteolate. Sepals 5. Petals 5, mostly obovate and emarginate. Stamens 

 commonly 20, inserted on an annular disk very near the base of the receptacle; filaments 

 filiform or spatulate but not flattened. Pistils many, becoming dry achenes in fruit, in- 

 serted on a hemispherical or conical receptacle; style terminal or nearly so, lateral or 

 basal, deciduous; ovules pendulous, attached at union of style and ovary, anatropous, 



