46 JOUENAL OF THE ROYAL HORTICULTURAL SOCIETY. 
THE BRITISH AND SWISS ALPINE FLORAS. 
By E. A. Xewell Arber, B.A., F.R.H.S., 
Trin. Coll. Camb. 
[Read May 2, 1899.] 
The flora of the higher mountain ranges of Europe is one of great interest, 
whether we have regard to its origin, its distribution, or to those special 
features which distinguish it from all other floras. The extreme beauty 
and diversity of form and coloar which is characteristic of alpine species 
is such as to impress all who have been privileged to visit alpine regions, 
whether professedly students of Nature or otherwise. The alpine flora of 
Switzerland is one of the best known of mountain floras, and many of 
the commonest plants seen in our rock-gardens are either species or 
varieties of species belonging to that flora. On the other hand the British 
alpine flora is smaller and comparatively insignificant, and on this 
account is rather apt to be overlooked. Many people are perhaps not 
aware that we have such a flora at all in Britain. If, however, we study 
the distribution of the plants which make up the British flora, we find 
that a certain number of species are confined to the summit of our higher 
mountains, and if we compare this flora v>'ith that of Switzerland we shall 
also find that nearly all these species are represented in the Swiss Alps, 
and as a rule occur there only at high elevations. I propose in this paper 
to give a comparative account of the British and Swiss floras, more par- 
ticularly in relation to tbeir alpine species. Such may, perhaps, be of use 
to those interested in the cultivation of alpines, and also to others who 
are familiar with our British plants, and who may at some time or other 
have an opportunity of extending their observations to the flora of the 
Swiss Highlands. 
As will be seen shortly, the British flora compares not unfavourably 
wdth the richer and more diversified flora of Switzerland ; a fact w^hich 
should stimulate the interest of all lovers of our wild flowers. 
A COMPAEISON OF THE BRITISH AND SwiSS FlORAS. 
Before considering the alpine division of the British and Swiss floras, 
it will be necessary first of all to shortly compare these two floras as a 
whole, in order to obtain some idea of the chief points of resemblance and 
difi'erence which they present. The number of Phanerogamic families, 
genera, and species represented or occurring in the British Isles and in 
Switzerland is as follows : — 
Plianerogams. 
1. Families represented in British Isles, 92; Switzerland, 102. 
Common to both floras, 89. 
2. Genera represented in British Isles, 515; Switzerland, GOO. 
Common to both floras, 460. 
3. Species* occurring in British Isles, 1,650; Switzerland, 2,350. 
Common to both floras, 1,250. 
* The number of species in the genera Rubus, Rosa, Hieracium, and Salix was 
calculated from Nyman's " Conspectus Florae Europaeae." 
