364 ISLAND LIFE 



tinent of Europe, are especially interesting, because they 

 demonstrate the existence of some peculiar conditions 

 such as would help to explain the presence of the other 

 peculiar species. Whether we suppose these American 

 forms to have migrated from America to Europe before 

 the glacial epoch, or to be the remnants of a vegetation 

 once spread over the north temperate zone, we can only 

 explain their presence with us and not further east by 

 something favourable either in our insular climate or in 

 the limited competition due to our comparative poverty 

 in species. 



About half of the peculiar forms are found in the 

 extreme west or north of Britain or in Ireland, where 

 peculiar insular conditions are at a maximum ; and the 

 influence of these conditions is further shown by the 

 number of species of West or South European plants which 

 occur in the same districts. 



We may here notice the interesting fact that Ireland 

 possesses no less than twenty species or sub-species of 

 flowering plants not found in Britain, and some of these 

 may be altogether peculiar. As a whole they show the 

 effect of the pre-eminently mild and insular climate of 

 Ireland in extending the range of some South European 

 species. The following list of these plants, for which I am 

 indebted to Mr. A. G. More, with a few remarks on their 

 distribution, will be found interesting : — 



List of Irish Flowering Plants which are not found in Britain. 



1. Poly gala vulgaris {var. grandiflora). Sligo. 



2. Campanula rotundifolia {var. speciosa). W. Ireland. 



3. Arenaria ciliata. W. Ireland (also Auvergne, Pyrenees, Crete). 



4. Saxifraga umbrosa. W. Ireland (also Pyrenees, N. Spain, Portugal). 



5. ,, geum, S. W. Ireland (also Pyrenees). 



6. ,, hirsuta. S. W. Ireland (also Pyrenees). 



7. Inula salicina, W. Ireland (Scandinavia, Middle and South Europe) 



8. Erica mediterranea. W. Ireland (W. France, SpRin, Portugal). 



9. ,, mackaiana {tetralix suh.-si^.). W. Ireland (Spain). 



10. Arbutus unedo. S. W. Ireland (W. of France, Spain, Portugal, and 



shores of Mediterranean). 



11. Vabeocia polifolia. W. Ireland (W. of France, Spain, and Portugal). 



12. Pinguicula grandiflora. S. W. Ireland (Spain, Pyrenees, Alps of 



France and Switzerland). 



13. Neotinea intacta. W. Ireland (S. France, Portugal, Spain, and 



shores of Mediterranean). 



