BUCKTHORN : IVY 



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Rhamnus Frangula, L. Alder Buckthorn (Fig. 123). 

 The globular drupe passes through dark brown to black, 

 and has very thin flesh. 



ft Fruit blue-black ; stones 4, obovoid, angular, 

 grooved at the back. 



R. catharticus, L. Buckthorn. Easily confounded by 

 a beginner with Prunus spinosa until attention is directed 



Fig. 124. Ivy, Hedera Helix. 1, flowering shoot; 2, leaf of a barren 

 climbing shoot; 3, flower in vertical section, enlarged; 4, floral diagram ; 

 5, fruit ; 6, seed (Wo). 



to the several stones, and the sub-opposite arrangement 

 of the leaves and spines : the persistent calyx-tube at the 

 base is also a useful character. 



92 



