FLORA OF SCOTTISH LAKES 
227 
the margins and in shallow, sheltered bays. Many of the shore rocks 
were covered with a luxuriant growth of lichens, particularly with 
Parnielia oniphalodes. Noteworthy also was the abundance of Bryo- 
phytes upon the littoral rocks, and in damp places. 
Loch Stroan. — The Airie Burn, which Hows from the north-east 
corner of Loch Skerrow, joins the river Dee after flowing northwards 
for about two miles. Thence the Dee, impetuous nearer its source, 
slowly meanders deep and wide through a flat alluvium, eastwards, 
for about a mile and a half, and then it flows into Loch Stroan. The 
north-west shore of this loch consists chiefly of sandy or muddy flats, 
the result of the detrital matter brought into it by the river Dee ; 
this is continuous with the extensive alluvial flats through which the 
river flows before entering the loch, and is overgrown near the water 
with Carex rostrata, etc. Farther away from the loch the drier 
portions are covered with moorland herbage of the grass-like type. 
Elsewhere the shores are stony or rocky, with a gentle inclination, 
merging gradually into grassy or heathery moor. Although slightly 
peaty, the water is clear and bright, so that vegetation at the bottom 
may be observed at a depth of 10 feet. Spongilla fluviatilis and 
Anodonta cygnea are both abundant in this loch. The bottom of 
Loch Stroan is to a great extent sandy or muddy, but no living 
vegetation occurs at a greater depth than 20 feet, as one might expect 
would be the case from a consideration of the clearness of the water. 
The reason is that beyond a depth of 15 to 20 feet the loch bottom is 
covered with the remains of grass-like moorland vegetation brought 
into the loch by winter floods as at Loch Doon (p. 219). The dead 
remains do not come so near the surface here as at Loch Doon, 
because of the scour caused by the river Dee in flood-time. In this 
case the bulk of such material is derived from the flat, marshy ground 
extending a few miles to the west of the loch, through which the 
river flows. On the east shore of the loch there is a great bank of 
such dead material, that has been deposited high above the normal 
water-level ; this, like that at the bottom of the loch, consists chiefly 
of the common moorland and marsh species of Carex, Scirpus, and 
Molinia. This loch has an abundant and varied flora, and a number 
of uncommon plants occur plentifully. 
Loch Whinyeon is somewhat circular in outline and about half a 
mile in diameter, occupying an exposed position over 700 feet above 
sea-level, three miles north from Gatehouse of Fleet. The water is 
clear and but very slightly peaty. The shore is everywhere stony or 
rocky, and consists chiefly of broken shale, the beds of which are fre- 
quently very highly inclined. The flora of the shore, as well as of the 
water, is extremely poor, but a number of Bryophytes clothe the 
littoral rocks. 
