28 ELEMENTS OP BOTANY. 



tinct or united. Fruit a group of akenes, a stone-fruit (Fig. 

 180), or a pome. Seeds 1 or few in each carpel, destitute 

 of endosperm. 



I. PRUN0S, PLUM, CHERRY, ETC. 



Trees or shrubs ; leaves simple, with stipules, which are 

 often small or fall off early ; calyx with a bell-shaped or urn- 

 shaped tube and 5-lobed spreading limb, falling off after 

 flowering ; petals 5 ; stamens 3-6 times as numerous, or 

 indefinite, inserted on the throat of the calyx-tube ; pistil 1, 

 long-styled, with 2 ovules, ripening into a single stone-fruit. 



a. (P. Americana), Wild Pluji. A tall' shrub or spreading 

 small tree, 10-15 ft. high, generally thorny, with large, obovate, 

 taper-pointed, coarsely serrate leaves, large, white, pedioeled flowers, 

 and tough-skinned oval or roundish, reddish or yellowish fruit, with 

 a sharp-edged or margined flattened stone. 



b. (P. CEUASus), Gardex Red Cherry, Sour C, Morello 

 C. A spreading tree 10-30 ft. high, with ovate or obovate serrate 

 leaves ; short-pediceled, rather large flowers, appearing earlier than 

 the leaves ; and sour, red fruit. Cultivated from Europe. 



c. (P. Virginiana), Choke Cherry. A shrub or small tree, 

 5-20 ft. high, with thin oval or obovate, pale, pointed, sharply serrate 

 leaves and small white flowers in short racemes. Fruit bright red, 

 turning at length to dark crimson, very puokery until fully ripe ; 

 stone smooth. 



II. POTENTILLA, CINQUEFOIL. 



Calyx flat, deeply 6-cleft, with bractlets at the base alter- 

 nating with the divisions. Petals 5. Stamens indefinite. 

 Ovaries small, on a dry receptacle, ripening into akenes. 

 Leaves compound. Flowers single or in cymes. 



a. (P. arguta). Upright Cinquefoil. An erect, stout, hairy 

 plant, 1-4 ft. high, with long-petioled pinnate root-leaves and few 

 stem-leaves, each of o-7 leaflets, the latter broadly ovate and cut- 

 toothed or serrate, downy underneath. Flowers large, in dense 

 terminal clusters, the petals whitish or cream-color. Perennial. 



b. (P. Canadensis), C'oMMON Cinijt"'-eoil. Stems slender, pro- 

 cumbent, silky-hairy, sending out long runners, with obovate wedge- 

 shaped leaflets appearing like 5 from the divisions of the 2 lateral 

 ones and 1-flowered peduncles in the axils of the leaves. Perennial. 



u. (P. argentea). Silvery Cinquefoil. Steins prostrate or 



