ROSE FAMILY 



the high-bush blackberries and should be the means 

 of making the various forms better known. It goes 

 without saying that in plants which are so confused as 

 rubi, intermediate and perplexing forms will be found; 

 but even these forms can be best understood when the 

 plants are broken up into their ixigning types." 



In Britton's " Manual of the Flora of the United 

 States and Canada " Rjibus argutiis and Riibiis frondosus 

 are considered as separate ; R. argiitus being the gla- 

 brate species, with the more southern habitat ; and R. 

 frondosus the Leafy-bracted Blackberr3\ 



Riibus nigrobaccus sativus, the Short-cluster Black- 

 berry, differs from the type in that it is lower, the 

 leaflets broader, less distinctly long-pointed, fruits 

 rounder and looser. It is the nondescript blackberry 

 of open fields and is the parent of the larger part of 

 the short-cluster or garden blackberries. 



Although the Blackberry group is very confusing 

 to an amateur, a few marked types can easily be deter- 

 mined ; the High-bush, R. nigrobaccus, with its mountain 

 form, R. allcgJienicnsis, and its unkempt poor relation, 

 R. nigrobaccus sativa, are not difficult to recognize. 

 The corymbose R. argutus, synonym R, frondosus, can 

 also be distinguished both in flower and fruit. The 

 straggling Dewberry, R. procumbcns, which once was 

 one but now is many, can be readily recognized in its 

 type. 



But to distinguish among the varying and connect- 

 ing forms which, grouped about these types, are now 

 considered species, is the task of the expert. More- 

 over, the experts do not altogether agree among them- 

 selves. It is probable that the group will always be 



152 



