A Family History. 199 



us that all these very divergent plants are ultimately 

 descended from a single common ancestor — the prim- 

 aeval progenitor of the entire rose tribe — whence they 

 have gradually branched off in various directions, 

 owing to separately slight modifications of structure 

 and habit, it is clear that the history of the roses must 

 really be one of great interest and significance from 

 the new standpoint of evolution. I propose, therefore, 

 here to examine the origin and development of 

 the existing English roses, with as little technical 

 detail as possible ; and I shall refer for the most part 

 only to those common and familiar forms which, like 

 the apple, the strawberry, or the cabbage rose, are 

 already presumably old acquaintances of all my 

 readers. 



The method of our inquiry must be a stiictly 

 genealogical one. For example, if we ask at the 

 present day whence came our own eatable garden 

 plums, competent botanists will tell us that they are 

 a highly cultivated and carefully selected variety of 

 the common sloe or blackthorn. It is true, the sloe 

 is a small, sour, and almost uneatable fruit, the bush 

 on which it grows is short and trunkless, and its 

 branches are thickly covered with very sharp stout 

 thorns ; whereas the cultivated plum is borne upon 

 a shapely spreading tree, with no thorns, and a well- 



