Flora of the Palonse Region 99 



vate, cuneate at base, coarsely dentate; lateral leaflets oblique: flowers 1.5-2 

 cm. broad: petals nearly orbicular, somewhat longer than the spreading 

 sepals: fruit oblong, the akenes on the surface. Thatuna Hills, common. 



161. ROSA. 



Rrect or climbing shrubs, usually with prickly stems: leaves 

 alternate, odd-pinnate, with adherent stipules; leaflets mostly 

 serrate: flowers solitary or in corymbs: calyx-tube cup or urn- 

 shaped, becoming fleshy in fruit, usually 5-lobed, without bract- 

 lets: petals 5, large, obcordate: stamens numerous, on the calyx- 

 tube: styles distinct or united: carpels indefinite, sessile at the 

 bottom of the calyx-tube: akenes numerous, enclosed in the berry- 

 like ealyx-tube. 



Flowers small, about 2 cm. in diameter. R. gymnocarpa. 



Flowers large, mostly solitary. R. nuTkana. 



Flowers large, mostly in corymbs. R. pisocarpa. 



R. gymnocarpa Nutt. Small shrub, about 1 m. high, armed with nu- 

 merous slender straight prickles: leaflets 5-9, elliptic, cuneate at base, ser- 

 rate, nearly glabrous, .5-2 cm. long; serratures and petioles glandular: 

 flowers mostly solitary, about 2 cm. in diameter: calyx-lobes acuminate, not 

 foliaceous, appendaged, deciduous from the fruit: fruit oblong or pear- 

 shaped, about 1 cm. long. Dry woods, Thatuna Hills. 



R. nutkana Presl. vStout, 1-2 m. high, armed with few but stout prickles: 

 leaflets 5-7, ovate or elliptic, obtuse, coarsely serrate, 1-3 cm. long, glabrous 

 or somewhat pubescent, usually glandular on the petioles and serratures: 

 flowers mostly solitary, 4-5 cm. broad: calyx-lobes glandular, foliaceous, 

 appendaged, persistent; calyx-tube globose, smooth: fruit globose, 2 cm. in 

 diameter; seeds large. 



var. hispida Fernald. Calyx-tube and fruit densely hispid-prickly. 



Both the type and the variety are common. 



R. pisocarpa Gray. Very similar to the preceding species, the leaves 

 usually finely pubescent: flowers smaller, about 3 cm. in diameter, usually 

 in corymbs: fruit ovoid or oblong, .5-1 cm. in diameter. Common in low 

 places. 



162. PIRUS. 



Trees or shrubs, not thorny (in ours): leaves simple or com- 

 pound: flowers in corymbed cymes: calyx urn-shaped, 5-cleft: 

 petals roundish or obovate: stamens numerous: styles 2-5: pome 

 flesh}' or berry-like, the 2-5 carpels or cells of a papery or cartil- 

 aginous texture, 2-seeded. 



P. sitchensis Piper. (Sorbtis sitchensis RoetnJ Shrub, 2-5 m. high, with 

 smooth bark; young branches pubescent: leaves pinnate, 12-20 cm. long; 

 leaflets 4-6 pairs, mostly oblong, acute or acuminate, simply or doubly serrate, 

 glabrous or nearly so, shiny above, 2-6 cm. long, 1-2 cm. broad: cymes dense, 

 compound, 8-12 cm. broad: flowers white, 8 mm. broad: calyx and pedicels 

 loosely woolly-pubescent: fruit bright red, about 6 mm. in diameter. 

 Thatuna Hills, in rich woods. 



