42 THE DISTRIBUTION OF HEPATICA IN SCOTLAND 
part of the western side; but some districts have been 
well searched, and show that the eastern part has a similar 
flora to that of the East Highlands, while the western part 
is similar to that of the West Highlands. It is to be noted, 
however, that, this part of Scotland being much the 
narrowest part of the mainland, the western species are 
more commonly met with throughout the whole district 
than is the case further south; yet they are very scarce 
near the east coast. The watershed runs comparatively 
close to the western sea-board, so, as is to be expected, the 
western species extend for some distance into the eastern 
side. The rainfall is shght near the east coast, being 
mostly under 30 in., and is less than 40 in. for some 
distance inland. In the western part it is less than that 
of the West Highlands, but it is still over 40 in. in its 
driest part, which is the extreme north, and it is more than 
50 in. over the greater part of the district. There is a 
considerable amount of cultivation in Caithness, but very 
little elsewhere except in the south-east corner of Ross-shire. 
This latter district has also a fair amount of woods, but 
in Caithness and in the northern part of the province 
generally natural woods are almost absent, owing to the 
want of shelter. ‘To this is due the absence of some species 
which are found in the East Highlands. 
In the southern part of the west coast of this province, 
the low-ground flora is quite similar to that of the West 
Highlands, and it is probable that there is little difference 
until the extreme north is reached, where there is little or 
no sheltered ground. On the north coast shelter is almost 
absent; the rainfall is also under 40 in. for almost the 
whole of its length. These conditions being unfavourable 
for the western species, we find they are almost absent in 
this part, the proximity of the sea not being sufficient in 
itself to counterbalance these disadvantages. In the excep- 
tional case of a western species not requiring shelter and 
inhabiting wet ground, such as Plewrozia, we find it 
abundant on moors near the north coast. 
The arctic-alpine flora, and the flora of the hills in 
general, of this province are poor in comparison with those 
of the Kast and West Highlands, especially those of the 
Breadalbane and Cairngorm Mountains, as the Torridon 
