1898-99.| A Bryological Excursion to Ben Lawers. 39 
started for our camp. But, hunger notwithstanding, we did 
not take the most direct route. We first went round Lochan- 
a-Chait, where some things struck us as being remarkable. 
For example, there was not a single water-plant growing in 
the whole loch. One or two small bits of alge were growing 
on the stones, but, taken altogether, I do not think there was 
as much as would have filled a table-spoon. There was no 
marshy ground around the shores, but between the water and 
the grass—which began with a clear edge, as if it had been 
cut off from six inches to a foot in height—there was a 
causeway of stones, varying in width from three to six feet, 
firmly packed together, and as level as if put in by the hand 
of man. Very few of the stones were large, and no loose 
stones lay about. In the smaller loch adjoining aquatic plants 
were in abundance. We suggested various theories to account 
for the remarkable difference in the state of vegetation of the 
two sheets of water, and of the paving of the shores, all of 
which were wide of the mark. But before we reached the end 
of the loch, Molus came and showed us how it was done. All 
day the air had been still, when suddenly a terrific hurricane 
arose among the rocks at the top of the mountain: we could 
hear it approaching, so we turned and waited. Down it came 
into the water, lifting a large sheet, which fell back into the 
loch with a great splash, as if emptied out of a gigantic basin. 
I have no doubt that the effect of these wind-storms upon the 
water is the cause of the absence of vegetation and of the 
paving of the shores. Curiously enough, we felt very little 
wind ; but, as showing the force with which it struck the loch, 
the water rose at our feet, and covered some large stones 
which lay between the two lochs, preventing us from crossing, 
which we were about to do. The water had risen nearly a foot. 
It took us a long time to get down to our camp, and we 
got nothing of special note except a large bed of Hypnum > 
stramineum. We looked for the Buxbaumia, but did not find 
any more of it. Arriving at camp about 8 o’clock, we put off 
no time in preparing and eating supper, which was very 
acceptable, after thirteen hours of fasting and mountain- 
climbing. After supper we arranged our specimens, but 
before we had finished it began to rain, and we retired to 
bed. It continued to rain all night, but we were quite dry, 
and had a fairly comfortable rest. Next morning, after break- 
