THE CLIMATAL DISTRIBUTION OF BRITISH PLANTS. 55 
mountains in the Lake District and on most of the Scotch 
mountains. Zone 6, the Super-arctic, only occurs on the 
higher Scotch mountains, north of the Clyde. 
The total number of species found in these two zones is 
about 240: of this number about 130 do not reach the 
highest zone, which can scarcely boast of more than 100 
species for its whole flora. 
I have now drawn your attention to some of the interesting 
plants of each of the three Agrarian and the three Arctic 
zones, but, before I conclude, I must just notice a class of 
plants, some 4o or 50, which are quite impartial in their 
distribution, and are found throughout all of the zones from 
sea level to the tops of the highest mountains, and from 
Cornwall to the Shetlands. Nearly all of these are among 
our commonest plants, such as the common Buttercup 
(Ranunculus acris), the Lady’s Smock (Cardamine pratensis), the 
Wood Sorrel (Oxalis Acetosella), the Harebell (Campanula 
votundifolia), plants with strong and hardy constitutions fitting 
them for any climate or soil, being what botanists call 
dominant types. A few on the other hand are not by any 
means generally distributed, but are found only on the sea 
shore and in mountainous regions, most often on high 
mountains. A conspicuous plant of this class being the 
Thrift or Sea Pink (Armeria vulgaris), which is so common a 
plant on sea shores. 
