PoTENTii.i.A. XLVIII. IIOSACETE. 251 



minute, subulate; sep. spreadiiij;, lonj^-acuminate, shorter than the narrow-obo- 

 vate, einartriiKile petals; siij. 00.— A delicate house-plant, with snow-white 

 double llowers. JNative of Mauritius. 



12. P () T E N T I L L A. 



Lat. potcntia, power; iu ulliision to its .fiipposeil potency in medicine. 



Calyx concave, deeply 4 — 5-clcft, with an cijual number of alter- 

 nate, exterior segments or bracteolcs ; petals 4 — 5, obcordate ; sta- 

 mens 00 ; filaments slender ; ovaries collected into a head on a small, 

 dry receptacle ; styles deciduous ; achenia 00. — Herbaceous or shrubby. 

 Lvs. pifuiaieli/ or falmately compound. Fls. solitary or cymosc^ mostly 

 yellow. 



* Leaves palmatcly trifoliate. 



1. P. NoRVKGicA. Norwegian Potcntilla or CinquefoU. 



Hirsute; st. erect, dichotomous above; Ifts. 3, elliptical or obovate, den- 

 tate-serrate, petiolulate ; cymes leal'y ; cat. exceeding the emarginate petals. — 

 Old fields and thickets, Arc. Am. to Car. Stem I— 4f high, covered with silky 

 hairs, terete, at length forked near the top. Cauline petioles shorter than the 

 leaves. Leaflets A — U' by \ — i', (lower and radical ones very small,) often 

 incised. Stipules large, ovate, subentire. Flowers many, crowded, with pale 

 yellow petals shorter than the lanceolate, acute, hairy sepals. Jl. — Sept. 



0. 7 hirsuta. T. & G. (P. hirsuta. Michx.)— Hairs loose, silky ; st. .slender, 

 erect, subsimple ; Uneer and middle lvs. equal, long-petiolate ; Ifls. roundish-obo- 

 vate, sessile, incisely dentate ; fls. few, petals rather conspicuous, nearly as long 

 as the calvx.— Dry fields. With reluctance I adopt the views of Torrey & Gray 

 in regard to this plant. 



2. P. TRiDENTATA. Ait. Trident or Mountain Potejiiilla. 



Smooth ; St. ascending, woody and creeping at base ; Ifts. 3, obovate-cune- 

 ate, evergreen, entire, with 3 large teeth at the apex ; cymes nearly naked ; pet. 

 twice longer than the calyx. — On the White Mis. ! and other alpine summits in 

 the N. States. Flowering stems G — 12' high, round, often with minute, ap- 

 pressed hairs. Petioles mostly longer than the leaves. Leaflets sessile, 9 — 18" 

 by 4 — 6", coriaceous, smooth. Flowers with white, obovate petals. Carpels 

 and achenia with scattered hairs. Jn. Jl. 



3. P. MINIMA. Haller. 



St. pubescent, ascending, mostly l-flowered ; lvs. trifoliate ; Ifts. obovate, 

 obtuse, incisely serrate, Avith 5 — 9 teeth above ; pet. longer than the sepals. — 

 Alpine regions of the White Mts. Stems numerous and leafy, 1 — 3' high. 

 Leaflets with the margins and veins beneath hairy. Flowers small. Petals 

 obcordate, Bracteoles oval-obtuse, narrowed at the base. 

 * * Leaves palmately 3 or b-foliaie. 



4. P. Canadensis. (P. sarmentosa. Willd.) Common CinquefoU. 



Villo.se pubescent ; st. sarmentose, procumbent and ascending ; lvs. pal- 

 mately 5-foliate, the leaflets obovate, silky beneath, cut-dentate towards the 

 apex, entire and attenuate towards the base ; slip, hairy, deeply 2 or 3-cleft, or 

 entire; pedicels dLxiWdixy , solitary; bracteoles of the calyx longer than the seg- 

 ments, and nearly as long as the petals. — Common in fields and thickets, U. S. 

 and Can. Stems more or less procumbent at base, from a few inches to a foot 

 or more in length. Flowers yellow, on long pedicels. Calyx segments lanceo- 

 late or linear. Apr. — Aug. 



0. p^tmila. T. & G. (P. pumila. PA.)— Very small and delicate, flowering 

 in Apr. and May. — I cannot perceive any difference betM'-een this and the above, 

 except its diminutive size and early flowering. In dry, sandy soils. Stems 

 about 3' high. 



y. simplex. T. & G. (P. simplex. Michx.)— Plant less hirsute ; st. simple, 

 erect or ascending at base ; Ifts. oval-cuneiform ; flowering in June — Aug. — In 

 richer soils. Stems 8 — 14' high. Leaflets about 1' long, | as wide. 



5. P. argentea. Silvery CinquefoU. 



St. ascending, tomentose, branched alwve ; Ift^. oblong-cuneiform, with a 



