194 ROSACEAE 



wide ; petals oblong-obovate, acutish at apex, % to 1 V2 lines long ; stamens 15 to 20 ; 

 filaments filiform, sinuous; stylos somewhat filan{lulai--])apillose ; aclienes about 4, 

 smooth VI' faintly ruj^ulose. 



Rocky ridges, 8000 feet : Tahquitz Peak, San Jacinto Mts. Aug. 



Note on relationship. — Potentilla callida, though closely related to P. shockleyi, differs in 

 a number of details. Tiie plants are more reduced and less glandular, the leaves and floral struc- 

 tures much smaller. The pubescence is finer. The calyx-tube lacks the pentagonal shape charac- 

 teristic of P. shockleyi. The stamens are three to four times as many, with long sinuous filaments 

 and anthers not one-fourth the size of those of P. shockleyi. The ranges are widely separated 

 and no intermediate plants have been collected. P. callida is knoAvn only from one station. 



Kefs.— PoTENTH^LA CALLIDA Hall, Univ. Cal. Publ. Bot. 1:86 (1902), type loc. Tahquitz 

 Peak, San Jacinto Mts., HaU 2611. Ivesia callida Rydb. N. Am. Fl, 22:286 (1908). P. shockleyi 

 var. callida Jepson, Man. 492 (1925). 



32. P. shockleyi Jepson. Sky Ivesia. Stems scapose, scarcely exceeding the 

 foliage, usually bearing a single pair of stipular bracts, 2 to 3 inches high, these 

 and the leaves densely tufted; herbage finely glandular-puberulent; leaves pin- 

 nate, the blades linear-oblong in outline, 1 to 2 inches long, the petioles V3 to 1/2 as 

 long; leaflets crowded, 2 to 4-parted into obovate obtuse bristle-tipped segments, 

 1 to l\i lines long; cjone 4 or 5-flowered, distinctly racemose; calyx-tube pen- 

 tagonal in fruit; flowers 2I/2 to 314 lines wide, on somewhat arcuate pedicels; 

 petals white, ovate, shorter than the calyx-lobes ; stamens 5 ; filaments linear- 

 subulate ; achenes 3 to 5, smooth. 



Rocky alpine peaks, 10,000 to 13,000 feet : eastern crests of the Sierra Nevada 

 from Placer Co. to Mono Co. ; White Mts. June-July. 



Locs. — Sierra Nevada: Tinker's Knob, Placer Co., Sonne; Mt. Dana, H. Sharsmith. "White 

 Mts.: Cottonwood Creek, Duran 1634. 



Refs. — Potentilla shockleyi Jepson, Man. 492 (1925). Ivesia shocTcleyi Wats. Proe. Am. 

 Acad. 23:263 (1888), based on spms. from Silver Peak, Alpine Co., Lemmon, and White Mts., 

 Mono Co., Shockley. Horlcelia shocTcleyi Rydb. Mem. Dept. Bot. Columbia Univ. 2:153, pi. 93, 

 figs. 8-14 (1898). P. decipiens Greene, Pitt. 1 :106 (1887) excluding synonyms, type loe. Truckee, 

 Sonne; not P. decipiens Jord. (1856). P. nubigena Greene, Erythea 3:36 (1895). 



33. P. gordonii Greene. Alpine Ivesia. Stems erect, nearly naked, 1 to 6 

 inches high, increasing in length % to 2 inches after anthesis ; herbage minutely 

 viscid-pubescent, or often somewhat hirsute ; leaves basal, pinnate, the blades 

 narrowly linear in outline, ^/^ to 3V2 inches long, on petioles 2 to 10 lines long; 

 leaflets numerous, densely set, 1 to 2^/2 lines long, 3 to 5-cleft nearly to the base 

 into obovate segments; cyme more or less dense; flowers 2^2 to 3 lines wide; bract- 

 lets linear or lanceolate ; calyx-tube cupulate ; petals yellow, l^/^ lines long, at first 

 almost orbicular, exceeding the calyx-lobes, becoming spatulate after anthesis and 

 then shorter than the accrescent calyx-lobes; stamens 5; filaments filiform; achenes 

 1 to 4, smooth. 



Alpine or subalpine, among rocks, 7800 to 13,000 feet : Yollo Bolly Mts. ; Sierra 

 Nevada from Tuolumne Co. to Modoc Co. North to Washington, east to Montana 

 and Colorado. July-Aug. 



Field note. — The root-crown is a thickened somewhat fleshy structure, which in some cases is 

 subfusiform or obovate-tuberous. 



Locs. — Inner North Coast Range: South Yollo Bolly, Jepson 14,175. Sierra Nevada: Mt. 

 Dana, Lemmon; Piute Peak, Tuolunme Co., Constance Douglas; Souora Peak, A. L. Grant 416; 

 Ebbetts Pass, Brewer 2071; Castle Peak (Mt. Stanford), Sonne 83; Eagle Peak, Warner Mts., 

 Modoc Co., Jepson 7971. 



Var. ursinorum Jepson. Leaves grayish with a short stiff pubescence ; stamens 5 (as in the 

 next two vars.). — Montane, 6800 to 9000 feet, Salmon and Scott mountains: Bear Creek, Trinity 

 Co., Alexander 4" Kellogg 313; Mt. Eddy, Siskiyou Co., Alexander 4" Kellogg 329. 



Var. megalopetala Jepson. Leaf -blades ^2 to 4% inches long, sometimes terete; cymes 

 sometimes less congested; calyx-tube in age saucer-shaped (as also in the next three vars.) ; bract- 

 lets oval to oblong ; petals conspicuous, orbicular to obovate-spatulate, exceeding the calyx -lobes ; 



