TRANSACTIONS OF SECTION C. 753 
the Red Crag. They cover an area 45 miles by 20 in extreme breadth, and in one 
place are nearly 150 feet in thickness, but they are not anywhere known to be 
underlaid by beds of Red Crag age. In the northern part of the Icenian area 
Astarte borealis occurs, and this species seems to mark a slightly more recent 
horizon of this zone. The Weybournian Crag, containing Tediina balthica, is only 
known to the north of Norwich, and extends from thence to the Cromer coast. 
The author now believes that these latter beds are distinct from, and of older date 
than, the Westleton shingle of Prestwich. 
3. The Meteorological Conditions of North-Western Europe, during the 
Pliocene and Glacial Periods. By F. W. Harmer, /.G.S. 
No satisfactory explanation has yet been offered as to the conditions under 
which originated the great sheets of shelly sand known to geologists as the Upper 
Crag, the littoral deposits of the North Sea in Pliocene times, which contain 
everywhere (over an area in Hast Anglia more than sixty miles in length) the 
dead shells of mollusca in the most extraordinary profusion. No such accumu- 
lations are now taking place on the shores of Norfolk and Suffolk, although 
molluscan life is more or less abundant in the adjoining seas. On the coast of 
Holland, on the contrary, dead shells are exceedingly common. : 
The occurrence of such débris is local rather than general, and seems to be due 
sometimes to currents, but more frequently to the action of stormy winds, which 
agitate the sea bottom to a greater or less depth. An examination of the daily 
weather charts issued by the Meteorological Office shows that movement of dead 
shells towards the shore at any place is for the most part in the direction of the 
gales which may there be prevalent. At present the cyclonic disturbances, to which 
East-Anglian storms are due, pass as a rule with their centres to the north-west 
of that district; and hence south-westerly and westerly gales are there common, 
and shelly dédris is driven on to the shores of Holland, and not on to those of the 
east of England. It would seem, therefore, that during the Pliocene epoch, 
strong winds from the east must have prevailed in the Crag area. At an early 
stage of the Red Crag period, mollusca now confined to the Arctic Circle had begun 
to establish themselves in the Crag basin, so that the glaciation of Scandinavia, 
attended with anticyclonic conditions over that country, had probably then com- 
menced. At present, when Scandinavia is anticyclonic, storm centres may be 
diverted from their usual course towards the south, as was the case, for example, 
in October 1898, causing south-easterly and easterly gales, with rough sea, on 
the eastern coasts of England. It is suggested that such conditions may have 
frequently prevailed there during the Crag period. 
The meteorological conditions of the northern hemisphere during the Glacial 
epoch must have been widely different from those of our owntime. At present the 
accumulation of ice sheets in the Arctic regions is local rather than general ; 
Greenland, for example, being glaciated, while the north of Scandinavia enjoys a 
milder climate. The latter is due partly to the Gulf Stream, but partly also to 
the prevalence of south-westerly winds, caused by the relative positions occupied. 
by areas of high and low pressure. Nansen states that a constant area of high 
pressure now exists over Greenland, and that the winds blow outwards from that 
country in all directions. Similar conditions probably obtained during the Glacial 
period over the great ice sheet of northern Europe, producing the most far- 
reaching changes on the climate of different parts of the northern hemisphere ; 
and this may, to some extent, explain the local character of the accumulation of 
great masses of snow and ice during that epoch. 
4. On some Paleolithic Implements of North Kent. 
By the Rev. J. M. Metxo, I.4., F.G.S. 
There is evidence from the abundance of flint implements that the prehistoric 
population of Kent must have been considerable. Implements are found at all 
1899. 3¢ 
