THE GENUS ROSA 287 



it as a tomentosa X pimpinellifolia hybrid — a designation 

 now wholly insufficient. The R. tomentosa of those days, 

 although shorn of the R. tnollis, was yet wide enough to 

 cover many microgenes now transferred to the Villoscc. Even 

 allowing for this far-flung R. totnentosa it is as certain as any- 

 thing can be that the names involuta, Sabim, Doniana and 

 occiden talis, if not others, were applied to plants of mollis X 

 pimpinellifolia parentage as well as to tomentosa (agg.) X 

 pimpinellifolia. Of course, southward of a line from York- 

 shire to Wales, the latter origin was certain ; northward of this 

 nothing was sure; mollis, omissa, tomentosa in the guise of any 

 of their segregates might very well enter, although in descend- 

 ing order of frequency ; firstly, because the period of flowering in 

 R. mollis more nearly synchronises with that oi R. pimpinellifolia; 

 secondly, because those two species, as in the coast denes of 

 Durham, occupy common habitats, and lastly, because 

 tomentosa vera and its microgenes thin out with extreme 

 rapidity northward. 



In Durham and Northumberland, R. rubiginosa is certainly 

 not a genuine native, and never, as far as I know, comes into 

 contact with R. pimpinellifolia ; these counties, therefore, 

 cannot produce R. biturigensis or any of its varieties. For 

 the specimen figured (Plate VIII. A) I have to thank Mr. 

 Barclay, and judging from its general appearance, I have very 

 little doubt but that in this case, and in the vast majority of 

 others, the hybrid had for its parents R. pimpinellifolia and 

 the R. rubiginosa form comosa. In the species-section 

 Agrestes no hybrids have been reported. 



The only other wild rose phen-hybrids known to me are 

 inter-Canine, and they include the liitetiana X coriifolia 

 referred to above and the mollis X canina from Norway. At 

 this juncture I have no intention of going into minute details 

 of these or of the numerous other hybrids I have seen growing 

 naturally, nor indeed do I intend, in general, to give full 

 descriptions at all ; whatever remarks I have to offer will be 

 reserved for the concluding portion of the paper, when, for the 

 first time, many of these crosses are figured. 



