ROSACEAE 67 



9. Calyx "mossy". (Moss roses). R. centifolia muscosa. 



Flowers not "mossy". (Cabbage roses). R. centifolia. 



10. Flowers double. (Tea roses). R. odorata. 

 Flowers single. 11. 



11. Leaves very rugose. R. rugosa. 

 Leaves not rugose. 12. 



12. Flowers yellow, early. (Yellow rose). R. foetida. 

 Flowers pink: stem and foliage pinkish. R. rubrifolia. 



PBUNUS. Plum. Cherry, etc. 



Deciduous or exceptionally evergreen trees or shrubs with 

 hard usually reddish wood with scattered ducts, the first of the 

 year sometimes slightly larger and forming a ring of a single 

 series, and fine medullary rays; rather slender terete twigs 

 sometimes transformed into or ending in spines; rounded con- 

 tinuous pale pith; alternate somewhat raised crescent-shaped 

 or half-round leaf -scars with 3 bundle-traces; minute often in- 

 distinct stipule-scars; triangular or ovoid sessile buds, the 

 terminal wanting in some groups, with several often denticu- 

 late exposed scales; chiefly lanceolate serrate petioled leaves; 

 moderately small white perfect polypetalous perigynous flowers 

 in axillary tufts or racemes ; and various-sized 1-seeded drupes. 



1. With scar left by terminal bud, in autumn. 2. 

 With terminal bud present. 10. 



2. Buds round-ovoid, scarcely longer than thick. 3. 

 Buds ovoid-conical, distinctly elongated. (Plum). 9. 



3. Leaves round-ovate, firm, glabrous: buds dark, with 



ciliate scales. (Apricot). P. Armeniaca. 



Leaves distinctly longer than broad. (Plum). 4. 



4. Buds puberulent, dark red. P. domestica. 

 Buds glabrous. 5. 



5. Scales red-brown, ciliate: leaves small. P. angustifolia. 

 Bud-scales brown, not ciliate. 6. 



6. Buds 1 obtuse: petiole with nectar-glands. P. hortulana. 

 Buds often acute: petiole wihout glands, 1, 



