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Rhamnaoeae. 



Rhamnus. Buckthorn. 

 (Family Rhamnaceae). 



Shrubs or rather small trees: 

 deciduous. Twigs rather slender, 

 rounded: pith moderate, rounded, 

 continuous, white. Buds moderate, 

 solitary, sessile or exceptionally 

 developing the first season, naked 

 (Frangula) or with some half- 

 dozen scales (Rhamnus proper). 

 Leaf-scars alternate, or in some 

 species opposite or in decussating 

 broken pairs, crescent-shaped or 

 half-elliptical, small, more or less 

 raised: bundle-traces 3 or joined 

 into a transverse series: stipule- 

 scars mostly minute, or stipules 

 small and persistent. References 

 under Adolphia. 



Cascara sagrada is much used in 

 medicine. 

 1. Buds scaly (Rhamnus) . 2. 



Buds naked (Frangula). 6. 



2. Buds chiefly opposite: shoots often spine-tipped. 3. 

 Buds alternate: not spiny. 4. 



3. Spines scarcely longer than buds. (1). R. cathartica. 

 Spines long and very pungent. R. japonica. 



4. Buds large (7-8 mm. long). (2). R. alpina. 

 Buds small (under 5 mm. long). 5. 



5. Twigs gray, often downy. 

 Twigs red or brown, glabrous. 



6. Buds long (8-10 mm.). (Cascara sagrada). 

 Buds short (scarcely 5 mm.). 7. 



7. Fruiting pedicels separate. R. Frangula 

 Fruiting pedicels several in a cluster. (4). R. caroliniana, 



(3). R. lanceolata. 

 R. alnifolia. 

 R. Purshiana. 



