542 Rydberg : Notes on Rosaceae 



The plant of northwestern North America is much closer to 

 the European Ariincus Aruncus, and differs practically only in the 

 long-acuminate leaflets. If any of the American species of Aruncus 

 should be reduced to the Old World species, it should be A. 

 acuminatus. A. Aruncus is common in cultivation and rarely 

 escaped. 



To these four species is to be added an East Siberian species 

 A. kamcJiaticus, which has been collected on Attn, the most 

 westerly of the Aleutian Islands. 



New York Botanical Garden. 



