158 ROSE ORDER 



Kelseya Rydberg 1900 

 ( Xamed for Kelsey, an American botanist) 



Sepals 5, united into a hairy calyx, petals 5, white, stamens 10, inserted 

 on the margin of the disk, pistils 5 ; flowers solitary and hidden at the ends 

 of the branches; leaves simple, imbricated ; tnfted perennial. 

 Stems 3-4 in. high ; leaves oblong-spatulate, 2-4 cm. 



long K. uniflora 



Opulaster Medicus 1799 Ntnebark 



(Lat. name of the wild cranberry tree) 



(Physocarpus Maxim) 



PI. 26, fig. 4. 



Sepals 5, united into a bell-shaped calyx, petals 5, white, on the throat 

 of the calyx, stamens 20-40, inserted with the petals, pistils 1-5, stigma ter- 

 minal, globose, pods 1-5, more or less inflated, 2-4-seeded, splitting when 

 ripe ; flowers in terminal corymbs ; leaves simple, palmately lobed ; shrub. 

 Bushy, 1-6 ft. high; carpels mostly 2-3, somewhat in- 

 flated or compressed, as long or longer than the 

 calyx O. opulifolius 



Petrophytum Nuttall 1840 

 (Gr. petra, rock, phyton, plant) 



Sepals 5, united into a silky-hairy calyx, petals 5, white, stamens many, 

 pistils 3-5, styles hairy below, follicles 1-2-seeded; flowers in a short spike, 

 leaves entire, crowded into a rosette ; stems woody, tufted or matted. 

 Stems in a dense mat ; leaves oblong-spatulate, 8-10 



mm. long P. caespitosum 



Potentilla Linne 1753 Potextilla, Cixouefoil 



(Lat. potens, powerful, from reputed medical properties) 



PI. 25, fig. 2. 



Sepals 5, united into a concave or hemispheric tube with 5 alternating 

 bracts, petals 5, rarely 4, yellow, rarely white or purple, stamens many, 

 seldom fewer, pistils many, style terminal, deciduous ; flowers solitary or 

 in cymes ; leaves compound, digitate or pinnate ; annual or perennial. 

 1. Flowers many in leafy cymes; leaves mostly of 

 3-5-leaflets, digitate ; style swollen toward the 

 base ; mostly annuals 

 a. Achenes with a large wart or swelling on the 



side P. paradoxa 



