68 EOSACE^. 



25. P. ciliata, Greene, 1. c. Habit and aspect of the last, but herbage 

 not purplish, villous : radical leaves with more than 20 crowded and 

 imbricated pairs of leaflets, these divided into 3 oblong linear entire 

 segments : cymes capitate-congested : calyx-segments lanceolate, exceed- 

 ing the turbinate tube and, with the narrower and shorter bractlets, 

 villous-ciliate : petals with linear-oblong blade and slender claw of equal 

 length : filaments scarcely dilated : pistils very few (1 — 3). — Owens' 

 Valley, Inyo Co., Dr. Kellogg. Plant with the aspect of the preceding 

 species, but in floral character an " Ivesia." 



26. P. purpurasceus, Greene, 1. c; Watson, Proc. Am. Acad. xi. 148 

 (1876), under Horkelia. Short-pubescent and somewhat pilose, 6 in. 

 high : leaflets 2 — 4-parted into oblong or obovate segments : fl. few, in a 

 rather open cyme : calyx % in. long, purplish ; bractlets small, narrow : 

 petals broadly cuneate-oblong, nearly equalling the calyx-lobes, rose- 

 colored : stamens 20 in 2 rows, the filaments in one row filiform. — Head 

 of Kern Eiver, at 9,000 ft., Roihrock. 



■M- -M- Leaflets in few pairs, 3-denlate at. ape.r. 



27. P. Tiling, Greene, 1. c; Regel, Gart. Fl. 1872. t. 711, under 

 Horkelia : H. iridentata, Torr. Pac. R Rep. iv. 84. t. 6 (1857) : Iresia 

 tridentata, Gray, Proc. Am. Acad. vii. 338 (1868). Stems slender decum- 

 bent, 6 — 12 in. high : herbage canescent with an appressed silky pubes- 

 cence : leaves mainly radical : leaflets cuneate-obovate to narrowly 

 oblong, % — 1 in. long, 3-dentate or entire : fl. small, in a much branched 

 dense cyme : petals white, spatulate to linear, little exceeding the calyx ; 

 filaments varying from subulate-dilated to filiform : achenes more or less 

 tuberculate. — Middle elevations in the Sierra. This and the preceding 

 completely nullify both Horkelia and Ivesia as supposed genera. 



* * *• Perennials ; leaflets oo , crowded or even imbricated on the rachis 



(except in No. 31) ; stamens 5 — ^20, uniform, filaments not dilated 



(except in No. 32); pistils very few, or 1 only. — Genus 



Ivesia, Torr. & Gray. 



■^ Stems leafy ; floivers eyntose-panicled. 



28. P. Pickeriii^i, Greene, Pittonia i. 105 (1887) ; Torr. in Bot. 

 Wilkes Exp. 288. t. 4 (1862), under Ivesia. Densely white-villous : leaf- 

 lets at first closely imbricated, in later development only approximate, 

 oblong, entire or 2— 5-lobed, 1 — 4 lines long : cymes dense, but arranged 

 in an open panicle : calyx 2 lines long ; bractlets linear : petals spatu- 

 late, equalling the calyx, yellowish : achenes 4 — 6. — A northeastern 

 species, reaching Sierra Valley, Lemrnon. 



29. P. nu^uiciilata, Greene, 1. c: Gray, Proc. Am. Acad. vii. 339 

 (1868). Resembling the last, but less densely villous : cymes less crowded : 

 calyx }^ in. long, the lobes and bractlets acuminate ; petals white, with 



