THE FLORA OF THE NORTH-EAST 31 
botanists from far and near. ‘Two of the three districts richest in our 
rarest Alpines lie within comparatively easy access—the Cairngorms them- 
selves, and the Lochnagar group of mountains with the hills and glens 
lying on the Aberdeenshire-Angus border. Though neither is so rich 
as Breadalbane, both areas offer great possibilities because of their wider 
range of extent and altitude, and because they have been much less 
thoroughly searched. The Cairngorms alone cover an area of about 
300 square miles, and extend for miles as a great elevated plateau of granite 
having a mean elevation of 3,800 ft. On the summit of this plateau and 
in the corries which gash its flanks, particularly those facing north or 
north-east, grow the hardiest of our Alpine gems. As, with a few excep- 
tions, all these are found growing within the Arctic Circle they are strictly 
* Arctic-alpine.’ 
The flora of the mountains consists of three different groups of plants : 
(1) Those which are of universal range (from the sea-level to the 
summits of the highest mountains), like Empetrum nigrum and Vac- 
cinium myrtillus ; (2) those which inhabit our rocky coasts and the 
high corries but not intermediate localities, like Sedum roseum and 
Saxifraga oppositifolia ; (3) those which normally grow above 1,000 ft., 
including a few which do not descend below high levels, like Juncus 
trifidus (above 2,200 ft.) and Luzula arcuata (above 3,700 ft.). Among 
the first group are many plants like Alchemilla and Euphrasia, of which all 
the mountain forms were formerly classified under the trivial name of 
vulgaris or officinalis. As the result of more critical study, and of com- 
parison with continental species, many upland forms now rank as species 
or sub-species. Though it is difficult to explain why, it is well known 
that certain corries and localities like Glen Callater, with its adjoining 
Corrie Kander, and Little Craigandal are far richer in Alpine species than 
others which seem equally well suited for them. A rocky slope on Little 
Craigandal lying at an elevation of 2,400-2,800 ft., where Prof. Balfour 
discovered Astragalus alpinus in 1842, is richer than any similar area north 
of the Dee. 
In Volume I of the Cairngorm Club Fournal Prof. Trail gave a list of 
‘The Flowering Plants and Fern Allies of the Cairngorms,’ which con- 
_ tains all those likely to be met with apart from critical species recently 
discovered. In the Annals of Scottish Natural History for 1908-9-10 
_ Mr. Frederick N. Williams discusses ‘ The High Alpine Flora of Britain ’ 
found at or over 1,000 metres (3,280 ft.), but it is necessary to explain 
that as he deals with all species recorded for that zone of altitude, he 
includes many species of universal range and not considered strictly 
Alpine. As an example of how species of the British type decrease with 
altitude we may note that on the summit of the Coyles of Muick (1,956) 
we find 12 out of a total of 19 ; on Mount Keen (3,077) 3 out of 8; while 
on Ben Macdhui (4,296) all seven—<Silene acaulis, Saxifraga stellaris, Salix 
herbacea, Luzula spicata, L. arcuata, Carex rigida, Festuca vivipara—are 
of the Highland type. Among the rarer Alpines of the Cairngorms are 
Sagina alpina, S. Boydii, Saxifraga nivalis, S. rivularis, S. cespitosa, 
many Hieracia, and several rushes, sedges and grasses. In addition to 
these Salix lanata and S. reticulata grow in Glen Callater and Corrie 
