48 JOUKNAL OF THE ROYAL HOETICULTUEAL SOCIETY 
occurs in Switzerland, and more than 50 per cent, of the total Swiss 
species in Britain. 
There are about 1,100 Swiss species which do not occur in Britain, 
and 150 of these are not indigenous. In the same way, of the 100 species 
pecuhar to Britain, as compared with Switzerland, at least 50 are 
naturalised. Many of the former are essentially maritime plants. It 
must not, however, be thought that maritime plants are necessarily 
absent from a country which, like Switzerland, has no sea-board. On 
the contrary there are several species indigenous to Switzerland, such as 
Glaucium luteum, Scrop. and Scirpus maritimus, L., which in Britain 
are almost entirely confined to our coasts. 
The great majority of those species which are peculiar to the British 
flora as compared with the S-vsdss, and vice versa the Swiss compared 
with the British, are distributed among the larger of the natural orders 
and genera. 
The following are the chief genera which show an increase' in species peculiar 
to each of these floras, as compared with one another. 
In the Swiss flora : — 
Hieracium 
Gentiana 
Senecio 
Saxifraga 
Crepis 
Campanula 
Potentilla 
Pedicularis 
Allium 
Viola 
Orobanche 
Trifolium 
Arenaria 
Androsace 
Rosa 
Galium 
Arabis 
Anemone 
Ranunculus 
Vicia 
! British flora : — 
Hieracium 
Potamogeton 
Fumaria 
Ranunculus 
Euphorbia 
Cochlearia 
Rubus 
Hypericum 
Arenaria 
Saxifraga 
Trifolium 
Juncus 
To sum up our consideration of these floras as a whole, we may 
estimate the total flora of 
Families. Genera. Species. 
Switzerland 102 600 2350 
Britain 92 51o 1650 
The indigenous flora confined to one country and not represented in 
the other : — 
Families. Genera. Species. 
SwitEerland 3 100 950 
Britain 3 45 350 
We see then that the British and Swiss floras, considered as a whole, 
are nearly related. In drawing deductions from a comparison of two 
floras such as these, there are several considerations which must not be 
overlooked. In the first place it must be remembered that while the 
British Isles form a natural botanical division of the earth's surface, 
this is not, however, the case with Switzerland. Switzerland, as defined 
politically to-day, has a flora which is complicated by the presence of an 
entirely different type of vegetation along its southern border. The 
Mediterranean flora, as the latter is termed, overlaps the true Swiss 
flora in many places, particularly in the Rhone Valley. The total 
Swiss flora is therefore greater than the true Swiss flora by a certain 
