Flora of Scottish Lakes. 
113 
1909-10.] 
level. It is 68 feet deep, and is situated in a somewhat open and wind- 
exposed position among grass-covered mountains. Its surroundings are 
treeless, except for the plantation about a small fishing lodge at the south- 
west end, below Craigronald, which rises immediately from the shore of the 
loch. 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 most abundant being Hyocomium flagellare, Hedwigia 
ciliata, Grimmia apocarpa, and Bhacomitrium aciculare. 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. At the north end there are associations of Phragmites 
communis, Juncus lamprocarpus, and J. acutiflorus ; a little bay on the east 
side has also a quantity of the first mentioned. On the north-west margin 
there are associations of Carex rostrata and Equisetum limosum. Groups 
of Heleocharis palustris and dwarf specimens of Ranunculus Flammula 
occur here and there all around the loch. Juncus alpinus and a dwarf form 
of Heleocharis palustris (p. 85) 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., resembling those of a sandy 
seashore 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 more or less carpeted 
with Littorella lacustris, Lobelia Dortmanna, and Isoetes lacustris, most of 
which are more or less overgrown with Algae, chiefly Batrachospermum 
vagum, Ulothrix aequalis, Binuclearia tatrana, etc. (p. 96). These plants, 
however, bear no external evidence of injury by the Algae, although Nardia 
emarginata and Scapania undulata, both of which grow abundantly on sub- 
mersed rocks, were much injured by the dense growth of such epiphytes 
upon them. Fontinalis squamosa and F. antipyretica occur in abundance 
upon the submersed rocks of the margin from the surface to 3 or 4 feet 
deep. In many places Juncus fluitans is extremely abundant from 2 to 5 
feet deep. In some parts, particularly at the south end, Sphagnum subse- 
cundum (p. 90) and Heterocladium heteropterum (p. 93), mixed with 
Scapania undulata, were abundant at the bottom from 2 to 8 feet deep, an 
uncommon situation for such plants. They may have been brought into 
the loch by one of the burns in time of spate, and then become adapted to 
the submersed environment. 
I could obtain no living plants in this loch beyond a depth of about 10 
feet, not because of the presence of vegetable detritus, nor of the opacity of 
VOL. xxx. 8 
