AUTHOR’S PREFACE 
Natural history is deservedly a popular subject. The mani- 
festations of life in all its varied forms is a theme that has 
never failed to attract alh who are not destitute of intelligence. 
From the days of the primitive cave-dwellers of Europe, who 
lived with mammoths and other animals now lost to the 
world ; of the ancient Egyptians, who drew and painted on 
the walls of their magnificent tombs the creatures inhabiting 
the delta of the Nile ; of the Greeks, looking out on the world 
with their bright and child-like curiosity, down to our own 
times, this old, yet ever new, theme has never failed. Never 
before was there such a profusion of books describing the various 
forms of life inhabiting the different countries of the globe, or 
the rivers, lakes, and seas that diversify its scenery. Popular 
writers have done good service in making the way plain for 
those who wish to acquaint themselves with the structures, 
habits, and histories of living animals ; while for students a 
still greater supply of excellent manuals and text-hooks has 
been, and still continues to be, forthcoming. 
But in our admiration for the present we forget the great 
past. How seldom do we think of that innumerable host of 
creatures that once trod this earth ! How little in comparison 
has been done for them ! Our natural-history books deal only 
with those that are alive now. Few popular writers have 
attempted to depict, as on a canvas, the great earth-drama that 
