FLOEA OF SCOTTISH LAKES 
229 
Loch Ken is one of the largest lochs in this part of Scotland, 
being only exceeded in size by Loch Doon. The loch proper is 
generally considered to lie between the grounds of Kenniuir Castle 
and the Boat of Rhone railway viaduct ; this portion is 4] miles long 
by -J mile wide. The river Dee joins the loch a little below the 
viaduct, and is continued as a narrow lake, in some places, however, 
half a mile wide, considerably to the south of Crossmichael. This 
lake-like portion extends the loch a further distance of over 4 miles, 
and is usually recognised as a part of the river Dee, although to the 
uninitiated it belongs to Loch Ken, and must be considered so from 
a botanical point of view. This sheet of water is thus about 8^ miles 
long, and v aries in width from a hundred yards to half a mile. Like 
Woodhall Loch, Loch Ken presents a mixture of the highland and 
lowland types of lochs, not only in its flora and physical conditions 
but also in scenic effect. At the head of Loch Ken the slight peati- 
ness of the water is modified by the drainage received from the 
villages and cultivated areas through which the Water of Ken flows. 
Both in the species and in the luxuriance of the vegetation at the 
northern end of the loch, there is evidence of a greater supplv of 
food-salts than is usual in peaty lakes. The water, although slightly 
peaty, is clear. In many places the shore consists of stones and rocks, 
which are usually angular or but slightly water-worn, and afford 
support to a very scanty flora. A narrow strip of such shore usually 
passes at once into meadow, moor, or woods. In other places the 
loch is bordered by bog, which makes it difficult to distinguish any 
line of demarcation between land and water. More rarely the shore 
may be sandy, or the water may be bordered by a bank without the 
intervention of a shore. In that portion of the loch above the rail- 
way viaduct vegetation seldom occurs at a greater depth than 6 or 7 
feet ; beyond that depth clay, mud, or vegetable detritus covers the 
bottom to the exclusion of living plants. In the lower portion, 
about Parton and Crossmichael, there is in places a bottom flora 
down to a depth of 12 feet. This is accounted for by the great body 
of peaty water from the river Dee scouring the bottom and washing 
vegetable detritus either into deeper places or down stream. It is 
also interesting to note that Isoetes lacustris, a plant very impatient of 
water rich in normal plant food-salts, was not found nearer the head 
of Loch Ken than the vicinity of Burned Island, whence it occurred, 
but quite sparingly, down to the viaduct ; after the loch had 
received the water of the river Dee, Isoetes became abundant, and 
continued so down to below Crossmichael. At the head of the loch, 
where the river Ken and the Knocknairling Burn enter, there is a 
very considerable area of deposit from the rivers, consisting of gravel, 
sand, or mud in a more or less marshy condition. These flats are 
