94 . Transactions. 
broken and accidental forms, littoral shells are absent, while the 
presence in great numbers of deep sea microzoa and mollusca 
proves the pelagic character of the deposit. Above this shelly clay 
there isa zone of clay without shells, covered in its turn by a layer 
containing recent and littoral shells. In no other deposit have 
the arctic deep sea and the temperate littoral periods been so well 
divided. There succeeded to the last Glacial epoch a gradual 
but comparatively rapid rise of sea level until the Garvel Park 
was immersed to a depth of at least 600 feet, and it became the 
habitat of an arctic pelagic fauna. During this rise considerable 
denudation of the boulder clay took place, a fresh ledge of which 
was annually disintegrated. The constant change of conditions, 
currents, and materials gave rise to the greatest diversity in the 
deposits, and during the rise and subsequent fall of the sea level 
our present shores became successively the littoral, the laminarian, 
and the pelagic zone, so that in many localities all kinds of 
bivalves are found mixed together in the same bed. It was con- 
tended by Mr Macfadzean that, as the same evidences are also 
found in Scandinavia and in N.E. America, the rise and fall of 
sea level were universal and simultaneous over this quarter of 
the world. He exhibited a classified collection of shells obtained 
by him from the Garvel Park deposits, and offered to present it 
to the Society if it was thought of suflicient interest to the 
members. 
Til. The Ancient Lake Dwellings of Scotland. 
By Mr G. F. Brack, Corresponding Member. 
Mr Black, in a lengthy communication on the above subject, 
referred to the first discovery of lake dwellings in Scotland in 
1781, and to the explorations carried on at Zurich in 1853-4, 
Since 1857 several have been noted in this country, and described 
by various archeologists, especially that at Lochlea, Tarbolton, 
Ayrshire, by Dr Munro and Mr R. W. Cochran Patrick, M.P. In 
reference to this lake dwelling, Mr Black gave a minute deserip- 
tion of the size and situation, and a list of the various relics found 
during the explorations. Mr Black remarks that lake dwellings 
have been found at Lochmaben, Sanquhar, Friars’ Carse, Loch 
Orr, Lochwood, Closeburn, Corncockle, and in the parish of 
Morton, in Dumfriesshire ; and, in conclusion, suggested that 
