258 THE FRESH- WATER LOCHS OF SCOTLAND 
ground covered with Carex, etc., and at one place there is an 
association of Typha latifoha. The shore along the north and east 
is flat and peaty, and a wide strip of it, exposed by the falling of the 
water, was more or less covered with Juncus fluitans which was 
reverting towards the terrestrial type. A number of species were 
observed at these reservoirs besides the above-mentioned, amongst 
them the following which are not very common in Area VII. : — 
Fontinalis antipyretica, Callitriche hamulata, Peplis Portula, Veronica 
scutellata, and Ranunculus pseudo-reptans. 
Loch Leven is situated in the lowest part of a somewhat oval 
strath, which is bounded by the Cleish Hills, Benarty Hill, the 
Lomond Hills, and the Ochil Hills. It is somewhat pear-shaped in 
outline, with the apex lying to the south-east. It is 3f miles long 
by 2 1 miles wide at the broadest part. The surface of the loch is 
350 feet above sea-level, and as the land for some distance around 
is below the 400-feet le\ el, it must, at a former period, have been very 
much larger. It was artificially reduced in size in 1845, when its level 
was lowered 4i feet. On account of the shallow marginal zone this 
slight lowering of the level reduced the area by about 1400 acres. 
For its size it is an extremely shallow loch, the greater portion of it 
being less than 15 feet deep. Indeed, along the east shore an area 
nearly three miles long by nearly a mile broad is mostly less than 
9 feet deep. It has, however, two depressions, each having a depth of 
about 80 feet— one to the west of St Serfs Island, and the other to the 
north-east of Scart Island. If the effluent were lowered 22 feet, so as 
to reduce the level of the loch by that amount, about 3000 acres of 
land would be reclaimed. There are six islands in the loch. The 
largest of them, called St Serf's Island, has a.n area of about 80 acres ; 
it is quite treeless, and is utilised as a rabbit-warren. Castle Island is 
covered with trees, and has an extent of about 5 acres. The other 
islands are quite small. The shores are everywhere flat and usually 
sandy, particularly on the east side, where the sand is sometimes blown 
into small dunes. More rarely the shore is composed of stones, or 
there is no shore because meadow-land comes down to the water's edge. 
In a few places there is a narrow zone of marsh extending a consider- 
able distance along the shore, as, for example, upon both the east and 
south sides opposite St Serf's Island. In many places there are large 
quantities of vegetable remains, chiefly those of Chara and Anacharis, 
lying upon the shore at the winter water-level. The flat shores of this 
loch are in many places very much exposed to wind, and due to this 
influence is the fact that some plants, which ordinarily grow erect, here 
assume a prostrate habit ; such, for example, as Equisetum arvense, 
Juncus bufonius, J. acutiflorus, J. supinus. Ranunculus Flammula, 
etc. There are two or three associations of Phragmites communis. 
