THE BOOK OF ROSES. 69 



vation has ever served to convert a yellow rose 

 into a red one ; or to produce composite leaves 

 on a fertile Barberry-leaved rose, or single leaves 

 on a fertile Rosa lutea. 



Under these three species, therefore, we shall 

 class our descriptive enumeration of all the 

 varieties of roses now in existence, as con- 

 tained in Part II. 



