62 ROSACEA, 



2. O. triflornm, Pursli, Fl. ii. 736 (1814). Soft-villoiis, 1 ft. higli : 

 radical leaves interruptedly pinnate with numerous crowded cuneate- 

 oblong incised leaflets : fl. large, few on long peduncles : calyx reddish ; 

 the linear bractlets 4 — 9 lines long,, equalling the lobes and the erect 

 petals : plumose tails of the achenes 2 — 3 in. long. — In the higher Sierra, 

 and northward and eastward to Arctic America. 



14. ALC'HEMILLA, Tragus. Herbs of various habit ; ours small 

 annuals with leafy stems, and minute green flowers fascicled in the axils 

 of the palmately lobed leaves, Galyx-tube urceolate ; limb 4— 5-cleft, 

 with or without as many minute bractlets or intervening teeth. Stamens 

 1 or 2, minute. Pistils 1 or 2 ; style basal or lateral ; ovule 1, ascending, 

 Achene ovate, compressed. 



1. A. arveusis, Scop. Fl. Oarn. ed. 2, i. 115 (1772) ; Linn. Sp. PI. i. 

 123 (1753), under Apltanes : A. occidentaiis, Nutt., probably. Slender, 

 simple or much branched from the base, 1 — 4 in. high, leafy, floriferous 

 and hirsute-pixbescent throughout, the calyx-tube densely hirsute : leaves 

 3-parted, the segments 2— 3-cleft : calyx-tube much contracted under the 

 4-parted limb, bractlets minute. Var. glabra. Glabrous, even to the 

 calyx-tube, which is broader than in the type, less constricted at the 

 orifice, with relatively larger bractlets. — Common along streams, borders 

 of thickets, or on open plains ; the variety in the valley of the Sacramento. 



2. A. cuueifolia, Nutt. in T. & G. Fl. i. 432 (1840). Differs from the 

 preceding in having leaves longer than broad, cleff at the summit only, 

 and a calyx-limb 5-cleft, without intervening bractlets. — Santa Barbara, 

 NuUall, and possibly within our limits. 



15. POTENTILLA, Brunfeh (CiNQUEFoiii. Five-Fingee). Herbs 

 (one species shrubby) with pinnately or palmately compound leaves, the 

 leaflets usually toothed or cleft, and adnate stipules. Flowers axillary 

 and solitary or in terminal cymes. Calyx from flat to campanulate, 

 5-cleft, valvate, with 5 alternating bractlets. Petals 5, rounded or elon- 

 gated, yellow, red or white. Stamens 5— oo ; filaments filiform or dilated. 

 Pistils 1 — 00 ; styles more or less lateral, deciduous. Achenes on a 

 glabrous or hairy dry (in one spongy-fleshy) receptacle. 



* Stamens 6 — go, uniform ; filaments filiform, or dilated at tlie base only. 

 -)— Petals minute, linear-oblong ; stamens 5. — Genus Sibbaldia, Linn. 



1. P. procuMibeus, Clairv. Man. (1811) ; Linn. Sp. PI. i. 284 (1753), 

 under Sil)baldia. Perennial, dwarf, creeping, the stems leafy and flowering 

 at the ends : leaflets 3, cuneate, 3-toothed at the truncate apex, I4 — 1 in. 

 long : peduncles shorter than the leaves : fl. cymose, yellow ; petals acute : 

 achenes 5—10, raised on short hairy stipes.— High summits of the Sierra. 

 4_ H— Petals spalulale, dark purple : stamens and pistils cc ; ripe receptacle 

 enlarged, spongy-fieshy. —Genus Comarum, Linn. 



