A 



44 FLOWERS OF FIELD, HILL, AND SWAMP 



20. Marsh-fivefinger, Purple Cinquefoil 



Poteniilla pa/ustris. — Family, Rose. Color, dark purple. 

 Leaves, pinnate, with 5 to 7 oblong, toothed leaflets, light green 

 above, downy beneath. Thne, summer. 



Calyx, open, i inch broad. 5-cleft, purple inside; bractlets 

 between the divisions. Corolla, of 5 purple petals, shorter than 

 the calyx. Stamens, numerous. 



Fruit, of several achenes in a roundish head on a large and 

 spongy receptacle. Flowers, few, clustered in a flat cyme from 

 a smooth stem which roots at the base. 



21. Silverweed 



P. Aiiserina. — Family, Rose. Color, yellow. Leaves, all from 

 root, pinnate, with 7 to 21 toothed leaflets, and smaller ones 

 between, dark green above, silky white beneath. Time, June 

 to September. 



Calyx and corolla, 5-divided. Five bractlets, often cut, lie 

 between the sepals. Stamens and fruit, like the last. 



The broad, open, yellow flower i^rovvs on a scape from a bed of 

 beautifully cut, handsomely colored leaves which are green above, 

 conspicuously white beneath. Like a strawberry plant, the silver- 

 weed spreads by jointed runners. Along the dunes bordering 

 Long Island bays I have found this pretty potentilla, its leaves 

 lapping the water. 2 or 3 feet long. 



22. Shrubby Cinquefoil 



{P. fruiicbsa) is another member of this group, growing in 

 marshy places ; tall, i to 4 feet high, with pinnate leaves, a 

 woody, much-branched stem, and yellow flowers terminal on 

 the branches. 



23. Swamp Saxifrage 

 Saxifraga Pennsylvanica ("rock-breakers," because some 

 species grow in clefts of rocks). — Family, Saxifrage. Color, 



