248 DR. J. W. HESLOP HARRISON ON 



parallel chains is no longer possible. Here at length we are 

 up against something so close to a species in the Linnaean 

 sense of the word that the unprejudiced observer can only- 

 regard them as such, despite the fact that few rhodologists 

 would look upon the chain as of lower value than a section or 

 subsection, comprising many species. 



Admitting the validity of our conclusion, we find that our 

 chain of collected forms assumes the familiar guise of the collec- 

 tive species, whereas the members of that chain sink to their 

 natural level of the^Jordanian species or microgene as I prefer 

 to call it. That the microgenes glide into one another depends 

 in all probability, for the most part, on hybridity, as I shall 

 demonstrate later. 



To avoid confusion I propose to call these chains section- 

 species, and on that basis the number I am prepared to admit 

 amongst the forms I have studied in a wild or half-wild con- 

 dition in the north amounts to eight. These are R. cani/ia, 

 R. Afzeliana^^, R. rubiginosa, R. agresfis, R. tnollis, R. 

 tomentosa, R. piinpinellifolia, and R. ci/i/iamomea, each of which 

 includes a fairly large number of microgenes, which, as they 

 exist in nature, are far from coinciding with the multitude 

 of alleged species set out with such lavish detail in the 

 various rose floras. Further, for ease in reference and to 

 harmonise my nomenclature as far as possible with that 

 current amongst botanists, I shall designate these section- 

 species by the sectional names EucaniiiLC, Afzeliance, Rubigi- 

 710SCB, Agrestes, VilloscB\, Toinentosce, Pimpinellifolice, and 

 Cinnaniomecz respectively. 



* The name Rjsa Afzdiana (a reinstatement due to Almquist) is used 

 to cover the two old collective species R. glaiica aiul R. coriifolia, the 

 separation of whijh was ridiculous in view of the feebleness of the 

 characters employed to differentiate them. The old <\>rii/oli(i forms 

 massed around var. Lintoiii are transferred to their natural allies the 

 RtibiginosiC. Similarly R. tonuiittlla and its satellites are removed to the 

 A^rcstcs. In the same way, antl for similar reasons, I have united the old 

 collective groups R. caniiia and R. diimclonim under A', canina. 



t In the Villosie I include all the related mollis and omissa forms. 



