CLASSIFICATION OF ANGIOSPERMS. 



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flowers are white and in compound cymes, the outer being sterile 

 and large and showy. The fruit is a reddish, globular, very 

 acid drupe, clinging to the branches all winter. The Snow-ball 

 or guelder-rose of the gardens is a sterile variety of this species. 

 Another variety (edule*) is also cultivated on account of its edible 

 fruits, particularly in Canada and the Northern United States. 



FIG. 392. Fruiting branch of Viburnum prunifolium. 



A number of species of Viburnum are rather common in 

 various parts of the United States, as the Maple-leaved arrow- 

 wood (V . accrifolium) , which is a small shrub with deeply 

 3-lobed, coarsely dentate leaves and small, nearly black drupes ; 

 Arrow-wood (V. dcntatiim}, with broadly ovate, coarsely den- 

 tate leaves and blue drupes, which become nearly black when 



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