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presume to explain, though the theory I have previously 
suggested of Ireland having originally formed part of a 
large continent, may afford some clue, as upon such a suppo- 
sition a colony of that people might wander with their herds 
to this extreme point of land, and settle there and finally 
become isolated by the gradual submergence of what now 
forms the bed of the Irish Channel and North Sea, or some 
narrow tract of land which connected them with the north 
of Europe. May not the occurrence of the Bear and Wolf in 
Britain, both, natives of the colder parts of northern Europe 
at the present day, also strengthen the above conjecture, and 
which may in like manner have wandered westward in pursuit 
of the Rein-deer, Megaceri, and other ruminating animals? 
I have already said that the age of the Megaceros will 
necessarily involve that of other quadrupeds whose remains 
are found in the same situations, and are universally admitted 
to have been its contemporaries, as the Mammoth Rhinoceros, 
Hippopotamus, &c, in this country, and the Mastodon in 
America, whose period of existence is supposed to date 
very early in the earth's history, or at least to an epoch 
anterior to man. That it has this effect I allow ; but this is 
no valid objection, unless we had positive evidence of the 
precise periods when the above large Pachyderms lived and 
ceased to live, which I venture to suspect we have not. In 
the last work published, which touches upon this subject by 
one of our most practical geologists, my esteemed friend 
Professor Phillips, he declares his belief that these very 
quadrupeds ceased to exist in the glacial epoch, an opinion 
which he doubtless considered was supported by geological 
evidence, and which he had arrived at by cautious induction. 
Yet while this very work was passing through the press, a 
most important discovery was made in the brick clay of 
the Aire valley deposit near Leeds, of the remains of 
the Hippopotamus, the Mammoth, and of the Urus ; and as 
