FLORA OF SCOTTISH LAKES 
225 
Loch Oich, but is smaller. The water is clear but slight^ peaty. 
At the west end the margin is formed chiefly by peaty banks ; 
elsewhere, except at the east end, which is flat and boggy, the 
shores are stony, rocky, or sandy, or the steep hillside enters the water 
directly without the intervention of a shore. The upper portions of 
the adjacent hills above the tree zone are mostly clothed with 
bracken and grass formations. The rank growth of the latter 
is here, however, much restricted, so that in comparison with Loch 
Doon there is but a small quantity of dead vegetation available for 
covering the loch bottom. Having noticed the relative scarcity of 
rank Molinia about the neighbourhood of this loch, I was anxious 
to discover to w^hat depth aquatic plants flourished at its bottom. 
Careful dredf^ino; revealed the fact that the livino; veo;etation here 
extends to a depth of 16 feet ; at greater depths the dead remains 
of Molinia, Carex, etc., cover the bottom, and no plants flourish within 
this zone. The flora of the loch is poor in the number of species, 
but some of the plants occur in great abundance. About the west 
end, at which is the efliuent, the loch is narrow, shallow, and bears 
a considerable vegetation. Beds of Carex rostrata are abundant, and 
on drier parts of the boggy shore these are gradually or suddenly 
exchanged for other marsh plants. At the east end the affluent 
passes through an extensive delta, which is overgrown with marsh 
plants common to the district. The shore rocks, which are not 
a particular feature of this loch, bear a number of common 
Bryophytes, etc. 
Loch Grennoch, by Cairnsmore of Fleet, is a fine sheet of M^ater 
2 miles long by | mile wide, at an elevation of 691 feet above sea- 
level, in a somewhat open and wind-exposed position among grass- 
covered mountains. Its shores are treeless, except for a plantation 
around a small fishing lodge at the south-west end, below Craigronald. 
The water is very clear, and but slightly peaty. The shore is rocky, 
with the exception of numerous bays of white syenitic sand. The 
exposed littoral rocks bear a number of common Bryophytes and 
lichens, but to no great extent. The aquatic flora is very poor in 
species, and the semi-aquatic plants of the shore are also poor in 
species and in numbers, the greater portion of the shore being almost 
devoid of such plants. Juncus alpinus, F?7/., and a dwarf xero- 
philous form of Heleocharis palustris (p. 181), grow upon the drier 
parts of some of the sandy bays. In certain of these bays the copious 
sand is blown up into miniature dunes, capped with Calluna, etc., 
and resembling a sandv sea-shore on a small scale. The bottom is 
for the most part very rocky, but there are considerable areas of sand 
or gravel extending from the margin to a depth of 8 or 10 feet. 
These areas are usually covered more or less with some of the bottom- 
15 
