tiom ihe HuLLETiN or the Tokrbv Botanical Club, 35- 535-542- iiyo8. 



Notes on Rosaceae — I 



I'KK Axel Rydherg 



The author has thought it advisable to pubHsh a series of 

 notes on this family, supplementary to his monograph in the 

 North American Flora, vol. 22, beginning on page 239. The 

 reasons for so doing, are : 



1. The plan of the North American Flora does not allow 

 many critical notes and explanations, and many facts worthy of 

 presentation must necessarily be omitted on account of lack of 

 space. 



2. It is not always evident from the synonymy alone, why a 

 certain name should be adopted in preference to another. 



3. It is often desirable to present the author's reasons for his 

 limitation of genera and species. 



4. In the North American Flora, only the types of new species 

 are given. It is often desirable to cite some more specimens, 

 which would help in identification of these species, when the types 

 are not accessible. 



Opulaster Medic. 



There may be some doubt as to whether this genus was 

 properly published. The original publication consists only of 

 citing Spiraea opulifolia L. as a synonym of Opulaster bidlatus 

 Medic. Icotorns Raf, Epicostorus Raf , and PJiysocarpa Raf , were 

 published in about the same way. The only name for the genus, 

 which was accompanied by an adequate description, was PJiyso- 

 carpus Maxim. ; but this, as well as PJiysocarpa Raf., is invalidated 

 by the older Physocarpon Necker,* and Physocarpiim Bercht. & 

 Presl,t which both have Latin diagnoses. Under the latter, there 

 are also two species named and described. There is, therefore, 

 no alternative left but the retaining of Opulaster as the name of the 

 genus, unless the making of a new name is preferred. 



* Elem. Bot. 2 : 164. 1790. 

 f Rostl. I : Ranunc. 14. 1823. 



535 



