PREFACE 
This volume is the outcome of the second series of “ Swiney 
Lectures ” on Geology which I delivered at the Victoria and 
Albert Museum in London in 1908. The subject chosen for 
these lectures was the “ Geological History of the American 
Fauna.” Instead of publishing the lectures, like the previous 
ones on the “ European Fauna,” with little alteration, I decided 
to amplify and rewrite them completely. In doing so I was 
enabled to bring out more clearly certain points in the 
geological history of the American animals which seemed 
to me of general interest. 
It is always difficult to choose a suitable title for a work of 
this kind. The one I have selected is brief yet comprehen¬ 
sive. At the same time, it may be urged that the origin and 
distribution of Man might reasonably be expected from the 
title, whereas it has been omitted in the text. This omission 
is mainly due to the fact that the literature dealing with the 
subject, exclusive of Man, is very extensive, while the origin 
and distribution of human races in America is treated in quite 
a distinct set of periodicals and books. 
An important feature of my researches is the elucidation of 
some of the problems connected with the cause and nature of 
the “ Ice Age ” or “ Glacial Epoch.” There is a considerable 
amount of faunistic evidence that both the Atlantic and the 
Pacific oceans were closed simultaneously in the north, result¬ 
ing in a higher temperature of these oceans and a greater 
snowfall in the countries surrounding them in the north. 
Similarly, if the Glacial Epoch had been due to a closing of the 
Arctic Ocean, the higher temperature prevailing in the Arctic 
