ROSE FAMILY 193 



Sandy flats or open gravelly or rocky ridges, 5000 to 11,800 feet : Sierra Nevada 

 from Eldorado Co. to Kern Co.; Tehachapi Mts. ; mountains of the Mt. Pinos region; 

 San Bernardino and San Jacinto mountains. June- Aug. 



Tax. note. — Potentilla santolinoides, notably constant thi'oughout its range, is an outstand- 

 ing member of the subgenus Ivesia and is remarkable for its single pistil and the mode of de- 

 hiscence of the anthers. It is mainly upon these characters that it was made by Eydberg the 

 type of his proposed genus Stellariopsis (Mem. Dept. Bot. Columbia 2:155). Keduction in the 

 number of pistils to 3 or 2 is, however, common in the Ivesia group of PotentUla and that an 

 extreme and constant condition has been attained in some species is not unexpected. Eeduction 

 to one achene often occurs in P. gordonii Greene and ocasionally in P. imguiculata Greene, 

 Anthers in P. santolinoides show a marked tendency toward the mode of dehiscence usually de- 

 scribed as "opening by a pore." Over twenty flowers were examined for this character. In the 

 majority of cases the anthers opened by a short subterminal slit; in certain specimens the slit 

 became rounded into a definite pore. This tendency was associated with a change in anther 

 shape, the valves becoming obovate rather than oval-elliptical. In a few specimens the anthers 

 appeared to open by a pore with no preliminary slit observable (Kaiser Crest, Fresno Co., A. L. 

 Grant 1013 ; Mt. Pinos, Peirson 3233 ; Huntington Lake, Ferguson 282). This latter condition ia 

 more usual in specimens from Southern California, while in the Sierra Nevada dehiscence by a 

 slit is the prevailing method. It appears, then, that the characters upon which Stellariopsis was 

 based are inconstant or unimportant, and that this group should not be segregated from the 

 subgenus Ivesia of Potentilla. 



Locs. — Myers sta., Eldorado Co., Ottley 932; Mt. Ralston, Eldorado Co., H. M. Evans; Ken- 

 nedy Mdw., Relief Creek, South Fork Stanislaus River, A. L. Grant 906 ; Benson Pass, Tuolumne 

 Co., Jepson 3375 ; Tuolumne Mdws., Jepson 4479 ; Lake Merced, Merced River, Jepson 3203 ; El 

 Capitan, Yosemite, Jepson 4358; Devils Postpile, Madera Co., A. L. Grant 1561; Kaiser Crest, 

 Fresno Co., Jepson 13,016 ; Kearsarge Pass, Jepson 880 ; Wildflower Lake, w. Inyo Co., Jepson 

 879 ; Cottonwood Creek, Inyo Co., Jepson 5073 ; Twin Lakes, Silliman Crest, W. Fry 363 ; Hockett 

 Mdws., Tulare Co., Culbertson 4315. Tehachapi Mts.: Tehachapi Peak, Dudley 313. S. Cal mts.: 

 Mt. Pinos; Mt. Alamos, Hall 6705; Holcomb Valley, San Bernardino Mts., Parish 1819; Tahquitz 

 Valley, San Jacinto Mts. (Bull. S. Cal. Acad. 24:14). 



Refs. — PoTENTlLJLiA SANTOLINOIDES Greene, Pitt. 1:106 (1887) ; Jepson, Man. 492, fig. 487 

 (1925). Ivesia santolinoides Gray, Proc. Am. Acad. 6:531 (1865), type loc. "Sierra Nevada", 

 Brewer, probably his no. 1661, above Nevada Fall. Stellariopsis santolinoides Rydb. Mem. Dept. 

 Bot. Columbia Univ. 2:155, pi. 95 (1898) ; N. Am. Fl, 22:292 (1908). 



30. P. muirii Greene. Granite Mouse-tail. Stems slender, naked except for 

 a pair of reduced or minute leaves at the middle, 2 to 6 inches high, villous-pubes- 

 cent; leaves pinnate, densely silvery-silky, the basal tufted, the blades y2 to 1^/2 

 (or 2%) inches long, terete with the numerous minute leaflets densely covering 

 the axis ("mouse-tail" type) and all but concealed by the pubescence; petioles 1 to 

 6 lines long; cyme with 2 or 3 forks, the flowers in subcapitate clusters, or the cyme 

 reduced to a single terminal head; flowers 1^ to 2% lines wide; petals yellow, 

 linear to oblanceolate-oblong, acute to obtuse, % to ll^ lines long, % the length 

 of the calyx-lobes; stamens 5, the filaments minute, nearly filiform; achenes 

 usually 2. 



Gravelly or rocky alpine slopes, 9500 to 11,500 feet : Sierra Nevada from Tuol- 

 umne Co. to Inyo Co. July- Aug. 



Locs. — Mt. Conness, J. B. Lemhert; Ireland Lake, Lyell Fork Tuolumne River, Kennedy; 

 Silver Pass, Fresno Co., A. L. Grant 1527; Evolution Basin, Fresno Co., E. Ferguson 489; Baker 

 Creek, w. Inyo Co., Duran 1811. 



Refs. — Potentilla muirii Greene, Pitt. 1:106 (1887); Jepson, Man. 492 (1925). Ivesia 

 muirii Gray, Proc. Am. Acad. 8 :627 (1873), type loc. Mt. Hoffmann, Muir. EorTceliu muirii Rydb. 

 Mem. Dept. Bot. Columbia Univ. 2:148, pi. 90, figs. 6-10 (1898). E. chandleri Rydb. Bull. Torr. 

 Club 28:177 (1901), type loc. Mt, Goddard, Hall ^ Chandler 700. Ivesia chandleri Rydb. N. Am. 

 Fl. 22:287 (1908). 



31. P. callida Hall. R-ock Ivesia. Plants dwarfed, caespitose, % to 2 inches 

 high; stems subscapose, with 1 or 2 pairs of reduced leaves or stipular bracts; 

 pubescence thinly hirsute; leaves basal, pinnate, the blades 6 to 10 lines long; peti- 

 oles 1 to 4 lines long ; leaflets about 13, 1 to 2 lines long, cleft to the base, the segments 

 roundish-oval to elliptical-oblong ; cymes 1 to 6-flowered ; flowers 1^ to 2% lines 



