131 
Perthshire, with the adjoining peaks ; 2nd, the Clova dis- 
trict in Forfar ; 3rd, Braemar. All these were long since 
searched by able botanists, as Hooker, Gardiner, Drummond, 
Wilson, Arnott, Greville, and others, but such is their rich- 
ness that a year hardly ever passes without some discovery. 
There are several causes for this richness, viz., elevation, 
moisture of climate, and nature of soil. 
Ben Lawers is the highest mountain in Perthshire, and 
attains an elevation of 3,984 feet above the level of the sea : 
its lower slopes consist of extensive moors, interspersed with 
peat bogs, which are the favorite abodes of various species 
of Sphagnum, Splachnum, Dissodon, Bryum, Mnium, and 
Hypnum. Its upper portion is composed of micaceous 
schist ; there it is that most of the great treasures of the 
mountain lie concealed — some of the species grow on preci- 
pitous ledges of rock, others in deep crevices, and others 
again on grassy turf, The additions of the last four years 
to the British flora from this ground are sufficient to attest 
its richness, viz : 
Tortula fragilis, Leskia nervosa, 
Mnium spinosum, Hypnum sulcatum, 
Timmia megapolitana, „ Bambergeri. 
Neither the preceding species nor the following, viz., Hyp- 
num plicatum, H. cirrhosum, H. Oakessii, discovered at 
dates varying from 1823 to 1850, have yet been found in 
Britain elsewhere than on Ben Lawers. 
Altogether about 180 species of mosses have been recorded 
from this mountain ; and when those of the woods, rocks, and 
walls round its base are added, the total of species for the 
district will amount to about 300. 
In Braemar the character of the soil completely changes, 
and with it the vegetation. The valleys and lower ridges 
are principally composed of slaty rocks; the higher moun- 
tains of the Cairngorm range of granite. In the valley 
Dr. Dickie has been fortunate enough to discover, on the 
