]_82 - ROSACEA. Horkelia. 



5. H. tenuiloba, Gray. Canescently villous, a foot high : leaflets 8 to 12 pairs, 

 small (2 or 3 lines long), cuneate-obovate, deeply 4 — 8-cleft with linear lobes, or in 

 the upper leaves narrow and few-lobed or linear and entire : flowers in close cymes ; 

 bracts short : calyx 2 lines long ; lobes linear, a little shorter than the oblong-spatu- 

 late petals. — Proc. Am. Acad. vi. 529 ; Watson, Bot. King Exp. 448. H. congesta, 

 var. tenuiloba, Torrey, Pac. P. Pep. iv. 84. H. congesta, Newberry, Pacif. P. Pep. 

 vi. 73. 



On S;mta Rosa Creek (Bicjelow) ; on Hat Creek, near Lassen's Peak, Newlcrry. 



6. H. Bolanderi, Gray. Densely hoary-pubescent, cespitose, the stems 3 or 4 

 inches high : leaflets numerous, about 2 lines long, cuneate-obovate, with 3 to 5 

 oblong or rounded lobes : flowers in a rather open cyme : calyx 2 lines long, about 

 equalling the oblong-spatulate petals. — Proc. Am. Acad. vii. 338; Watson, 1. c. 



Var. Parryi, Watson. Less densely pubescent : leaflets often broadly and ab- 

 ruptly cuneate : flowers larger, 3 or 4 lines long. 



Dry alkaline soil, near Clear Lake, Bolander. The variety in the mountains above San Ber- 

 nardino, Parry, 1875. 



7. H. purpurascens, Watson. Pubescent and somewhat villous, 6 inches 

 high: leaflets numerous, approximate, 2-4-parted; segments oblong to obovate, 2 

 or 3 lines long or less : flowers few, in an open cyme : calyx purplish, about 4 lines 

 long; bractlets small and narrow: petals rose-colored, broadly cuneate-oblong, nearly 

 equalling the calyx : stamens 20 ; the filaments opposite to the calyx-lobes and 

 bractlets subulate, the alternate ones filiform : carpels 20 to 25. — Proc. Am. Acad. 

 xi. 148. 



In the Sierra Nevada, about the head-waters of Kern River, at 9,000 feet altitude, Dr. J. T. 

 Eothrock. Peculiar in the number of the stamens. 



++ ++ Leaflets few-toothed at the truncate apex. 



8. H. tridentata, Torr. Pubescence silky-villous, mostly appressed, often 

 dense : stems usually a span high or more : leaflets 2 to 5 pairs, cuneate-obovate to 

 narrowly oblong, usually 3-toothed at the apex, a half-inch to an inch long : flowers 

 on slender pedicels in a contracted much-branched cyme : calyx 2 or 3 lines long, a 

 little shorter than the linear to broadly spatulate petals : filaments often filiform or 

 the longer ones onty slightly broader below, sometimes dilated : receptacle often 

 villous: akenes occasionally rough-tuberculate. — Pacif. R. Pep. iv. 84, t. 6. Ivesia 

 tridentata, Gray, Proc. Am. Acad. vii. 338. H. Tilinqi, Pegel, Trudi Peterb. i. 

 151, & Gartenfl. 1872, t. 711. 



In the Sierra Nevada, from Yosemite Valley to Plumas Co., Mrs. M. E. P. Ames. A species 

 which goes far in its variations to unit? this genus with the next. 



17. IVESIA, Torr. & Gray. 



Stamens 20, in one to three rows ; filaments slender, filiform. Carpels few, upon 

 a villous receptacle : styles filiform. — Herbaceous perennials of the Sierra Nevada 

 and eastward ; leaflets usually numerous and parted or very deeply cleft, often 

 closely imbricated ; flowers white, yellow, or purple, in cymes or open panicles. 

 Characters otherwise as in Horkelia. — Gray, Proc. Am. Acad. vi. 530 ; Watson, 

 Bot. Kiug Exp. 448. 



* Flowers in rather close panicled cymes: stems slender, mostly leafy : not alpine. 



1. I. Pickeringii, Torr. Densely white silky-villous, about a span high : 

 leaflets very numerous, at first closely imbricated, 2 - 5-parted or lobed or often 

 entire, the segments oblong, 1 to 4 hues long : stems panicled above, the cymes 

 densely many-flowered : calyx 2 lines long or less ; bractlets linear : petals yellow- 



