mee. Amey LA. N TGA, 

THE DISTRIBUTION OF BIRDS IN CEYLON AND ITS 
RELATION TO RECENT GEOLOGICAL CHANGES 
IN THE ISLAND. 
By W. E. Wart, C.GS. 
HE fauna of an island can never fail to be of interest. 
Owing tu its isolation there are usually to be found within 
its limits a greater number of peculiar species and gencra than 
can be expected from a continental area of the same extent. 
If the island has been separated from adjacent lands for only 
a short geological period, the insularity of its fauna is not 
well developed ; but the longer the period of separation, the 
more marked become the differences. 
As a consequence, the study of an insular fauna will throw 
considerable light upon its geological history, corroborating 
the geological evidence, or supplementing gaps in the geological 
record. ‘Take, for instance, the British Islands. We know 
that at a quite recent geological period—that of the great 
Ice Age—the whole of the north of Great Britain was covered 
by an enormous sheet of glacier ice, and that even the south 
of England was too cold to support anything but an arctic 
fauna. When the ice receded and the temperature grew 
warmer, the present temperate fauna gradually came over 
from the Continent. To allow for the influx of mammals there 
must have been a land connection, not only between England 
and the Continent, but between England and Ireland. 
Now, a fair number of animals which came over into England 
failed to reach Ireland, so it is evident that Ireland became 
an island after the Ice Age, but before Great Britain became 
separated from the Continent. 
This comparative study of the distribution of animals is of 
the greatest importance in working out the geological history 
of Ceylon, as our geological record is so imperfect. 
The rocks of which the Island is composed belong to the 
oldest geological period, and it is fairly certain, from the 
] 6(7)14 
