50 
PROCEEDINGS OF THE PERTHSHIRE SOCIETY OF NATURAE SCIENCE. 
Central Europe were compelled to retreat to the moun¬ 
tains by the incoming hosts of temperate species which 
crowded them out of the low grounds. There can 
be no doubt that, after the final disappearance of our 
ancient mers de glace, it was this arctic-alpine flora that 
clothed the British area. Our commonest animals at 
that time were reindeer, elk, and so forth. As these 
northern plants and animals retired to higher latitudes, 
they were closely followed by the great body of temperate 
species which constitute what is now the prevailing flora 
of Great Britain and similar latitudes of the Continent. 
Our islands had thus been clothed and peopled by plants 
and animals which had immigrated from the Continent; 
and as this immigration took place in post-glacial times, it 
showed that the British area after the disappearance of 
arctic conditions formed part and parcel of the European 
Continent, And not only so, but as the present floras of 
the Faeroe Islands and Iceland are Scandinavian in type, 
and as they could not have existed in those islands during 
the last glacial epoch, it follows that they must have been 
introduced in post-glacial times. This, as Dr Geikie re¬ 
marked, implied a continuous or nearly continuous land- 
connection between those far-off islands and the European 
Continent,—the connection in all probability having been 
by way of Scotland and the Outer Hebrides. A sub¬ 
marine ridge at about a depth of 200 or 250 fathoms ex¬ 
tended across from the Hebrides to the Fieroes, and this 
is probably the submerged land-connection which obtained 
in early post-glacial times. 
Having pointed out the facts bearing upon the ques¬ 
tion of changes in the geographical outline of North- 
Western Europe, that of climatic changes was next 
considered. It was pointed out that the former greater 
abundance of southern species in our northern seas de¬ 
noted a formerly higher temperature for those waters. 
These southern forms were now dying out. It was self- 
evident that the immigration of these species into our area 
must be of post-glacial date, since it is quite impossible that 
they could have outlived the conditions that obtained dur¬ 
ing the last glacial epoch. Clearly, then, the Gulf-stream, 
within a comparatively recent period, had flowed into 
these northern seas in a much greater volume. And these 
facts and inferences were in keeping with the evidence 
supplied by the buried forests of the peat-bogs. At the 
time Mediterranean molluscs were immigrating into 
northern seas, oaks and pines were covering immense 
regions which are now bare and treeless. This was what 
he termed the genial post-glacial period. It is to this 
period that the lower buried forests of our peat-bogs 
belong. 
The next stage is represented by the raised beaches, 
which indicate a former submergence of the land. The 
British area 'then became insulated, and the climate 
deteriorated. The great forests decayed more or less 
rapidly, and became buried in growing peat. The climate 
was at once humid and cold: the humidity giving rise 
to a vast increase of the peat-bogs throughout all North- 
WesternEurope;—and the cold once more causing perennial 
snow-fields and glaciers to appear in Scotland. At this 
time the sites now occupied by all our great seaport towns 
were under water. All the wide earse-lands of Forth and 
Stirling and Gowrie were drowned, and Neolithic man 
lived along what were then the sea-coasts, where he has 
left piles of shells, and other relics, such as harpoons, 
stone hammers, hearthstones, &c., to testify to his former 
presence. 
Eventually the climate improved, and the sea at the 
same time retreated to a lower level than at present. 
Again the forests began to spread, and this so vigorously 
that they by and by covered wide areas which had formerly 
been waste heath and bog. This was the period of the 
upper or newer forest-bed of the peat-bogs in this country 
and the Continent. It was followed by a final submergence 
of the land, during which the climate would appear to 
have again become colder and more humid, and thus en¬ 
couraged a new and vigorous growth of peat, underneath 
which wide areas of forest-land were eventually buried. 
The last great change has been a retreat of the sea from 
the 25 to 30 feet level to its present position, probably 
accompanied by a lessened humidity, as would seem to be 
indicated by the fact that the peat-bogs over wide areas in 
Norway, Sweden, Denmark, Germany, and our own 
slands, appear to have ceased to extend themselves,—in 
many places, indeed, they are even dying out and decaying 
away. 
ANNUAL DINNER. 
December 16th, 1881. 
The Annual Dinner took place in the Salutation Hotel, 
Perth, on Dec. 16th. The President, Dr Geikie, F.K.S., 
occupied the chair, and there was a good attendance of 
members, who, as usual, alone had the privilege of being 
present. 
In proposing the toast of the evening, “ The Perthshire 
Society of Natural Science,” Dr Geikie insisted upon the 
importance of every member being, so far as in him lay, a 
