450 MALACEAE 



acuminate at the apex, cuneate at the base, with 2-4 shallow lobes towards the 

 apex, serrate, with gland-tipped teeth, slightly pubescent above and at the 

 junctions of the veins beneath; corymb pilose; sepals pubescent within, ovate, 

 acuminate, sometimes with stalked glands; stamens 10; styles 3 or 4; fruit glo- 

 bose, 8-10 mm. thick, red, slightly xmbescent. Banks: nw Mont. Submont. 

 My-Jl. 



8. C. columbiana Ho well. A shrub or small tree, much branched; leaves 

 rather thin, obovate or ovate, 2-6 cm. long, cuneate at the base, with 3 or 4 

 pairs of sharp lobes, sharply and doubly toothed, sparingly long-hairy, especially 

 along the veins; corymb sparingly long-hairy; sepals triangular, long-pointed, 

 slightly long-hairy within, glandular-toothed; stamens about 10; fruit pear- 

 shaped or ellipsoid, 8-12 mm. long, scarlet. C. Piperi Britton, a form with 

 hairy corymb and fruit. River banks: B.C. N.D. Ida. Ore. Submont. 



FAMILY 62. AMYGDALACEAE. PLUM FAMILY. 



Trees or shrubs, with alternate simple leaves and deciduous stipules. 

 Flowers perfect, in ours regular. Hypanthium well developed, mostly cup- 

 shaped, with an angular disk at the mouth bearing the stamens. Sepals 

 and petals 5. Stamens in ours 10 or more. Pistils usually solitary. Fruit 

 a drupe. 



Drupe with pulpy exocarp ; leaves not fascicled. 1. PRUNUS. 



Drupe with almost dry exocarp, pubescent; leaves fascicled. 2. EMPLECTOCLADUS. 



1. PRUNUS L. PLUMS, CHERRIES. 



Shrubs or trees. Leaves alternate, deciduous, usually toothed. Flowers 

 perfect, either solitary, umbellate or corymbose from scaly buds, or corymbose 

 or racemose at the ends of leafy branches. Hypanthium in ours campanulate 

 or turbinate. Sepals 5, imbricate. Petals 5, imbricate, inserted with the sta- 

 mens on a disc in the throat of the hypanthium. Stamens 15-30; filaments 

 filiform, distinct. Drupe, with a fleshy exocarp, often with a bloom; stone 

 bony, smooth. 



Flowers few, umbellate or corymbose. 



Fruit with a ventral groove and flat stone. (PLUMS.) 



Leaves oval or orbicular, rounded at the apex. 1. P. subcordata. 



Leaves lanceolate to obovate, acute or acuminate. 



Trees or shrubs, usually spiny; leaves serrate to near the base. 



2. P. americana. 



Low undershrub, unarmed; leaves entire at the base. 3. P. prunella. 

 Fruit without a ventral groove; stone subglobose. (CHERRIES.) 



Creeping shrub; flowers umbellate. 4. P. Besseyi. 



Erect shrubs or trees. 



Hypanthium decidedly obconic; flowers umbellate from naked lateral buds. 



5. P. ignota. 



Hypanthium campanulate or turbinate; flowers more or less corymbose. 

 Leaves acute, serrate. 



Corymbs naked. 6. P. pennsylvanica, 



Corymb usually subtended by 1 or 2 leaves. 7. P. corymbulosa. 



Leaves obtuse or rounded at the apex, crenulate. 



Leaves glabrous. 8. P. emarginqta. 



Leaves pubescent. 9. P. prunifolia. 



Flowers many, racemose on leafy branches. (CHOKE CHERRIES.) 

 Leaves more or less pubescent beneath. 



Peduncles stout; pedicels pubescent, shorter than the fruit, deciduous; leaves thick. 



10. P. valida. 

 Peduncles slender; pedicels glabrous, longer than the fruit, persistent; leaves 



rather thin. 11. P. demissa. 



Leaves glabrous on both sides. 12. P. melanocarpa. 



1. P. subcordata Benth. Tree up to 8 m. high, with stout spreading 

 branches, finely pubescent, becoming glabrous; leaves oval to orbicular, 2.5-7 

 cm. long, finely double-toothed, pale beneath; sepals entire, rounded; fruit 2-3 

 cm. long, dark r,ed or yellow. Rocky hills: Ore. Ida. Calif. Submont. 

 Mr-My. 



