PREFACE

HE object of the present volume is to delineate and describe, so far as the state of our knowledge permits, the present distribution of the higher animals over the surface of the Earth. This undertaking, with the exception of Plate 36, is not based upon any previous work of a similar nature, but is entirely the result of original researches into the zoological literature of all countries. All the families
___________________ of Mammals, Birds, Reptiles and Amphibians, together with several of the more
important genera and species, have been dealt with, while the work embraces in addition most ׳ of the families of Fishes and a selection of families and genera of Molluscs and Insects.
The authors fully realise that in a work of this kind it is impossible to attain absolute accuracy. Zoological literature has assumed such enormous proportions that a complete survey is quite impracticable. No pains have been spared, however, to lay under contribution all the more important publications relating to the faunas of the various countries. The distribution of animal life in many areas has not been investigated in sufficient detail to afford the necessary data, and the range is then impossible to define with precision. This applies particularly to countries like Siberia, and in such instances the authors have been unable to do more than indicate the known outposts and join them by a more or less hypothetical line. But they venture to think that, for all practical purposes,
the work is sufficiently accurate.
In the mapping of the distributions it has been thought desirable, for the sake of clearness, to have numerous small maps, rather than risk confusion by crowding too many families on one Plate. Thus, by the use of over two hundred maps, together with distinctive colouring, it is hoped that all complexity has been avoided. In each case the data have been drafted on large-scale maps and then
carefully reduced to the smaller scale for the Atlas.
In the Text, a short historical account is given of the various systems propounded for the sub- *׳ division of the World into Zoo-geographical Regions, wherein the views of the leading authorities are considered. Their schemes are shown on a special Plate. Most of these are based upon the study of particular groups of animals—such as Mammals—but that of Dr Alfred Russel Wallace has a wider bearing, and hence has been accepted as a basis for the text of the present volume. In Part II. the various Regions and Sub-Regions of this author are defined, and an account given of their characteristic and peculiar animals, with original Tables, giving a numerical summary of the
families of terrestrial Vertebrates occurring in these areas.
The main portion of the Text is designed to afford concise information regarding the groups of animals whose	distribution	is shown on the	Plates. A census	has been given, where possible, of
the	number of	known species in each family,	based upon the latest information. The nature of the
haunts frequented, a general statement as to the constituent animals of the various groups, the peculiarities in their distribution, and other desirable particulars have been furnished.
The Part	devoted to	Bibliography contains a list, limited	to about a thousand titles, of the
more important books and papers dealing with the animals of the various Regions. The titles are arranged alphabetically under the authors’ names, and are then grouped primarily under the Regions, and secondarily under the various classes of animals.
Lastly, in	a work of	this nature, where	so many animals	and countries have been passed in
review, a full and comprehensive Index has been deemed a necessary adjunct.
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