Xi PREFACE. 
therefore designed a series of six maps of the regions, drawn on 
a uniform scale, on which the belts of altitude are shown by 
contour-shading, while the forests, pastures, deserts, and peren- 
nial snows, are exhibited by means of appropriate tints of colour. 
These maps will, I trust, facilitate the study of geographical ° 
distribution as a science, by showing, in some cases, an adequate 
cause in the nature of the terrestrial surface for the actual dis- 
tribution of certain groups of animals. As it is hoped they will 
be constantly referred to, double folding has been avoided, and 
they are consequently rather small; but Mr. Stanford, and his 
able assistant in the map department, Mr. Bolton, have taken 
great care in working out the details from the latest observations; 
and this, combined with the clearness and the beauty of their. 
execution, will I trust render them both interesting and in- 
structive. 
In order to make the book more intelligible to those readers 
who have no special knowledge of systematic zoology, and to 
whom most of the names with which its pages are often crowded 
must necessarily be unmeaning, I give a series of twenty plates, 
each one illustrating at once the physical aspect and the special 
zoological character of some well-marked division of a region. 
Great care has been taken to associate in the pictures, such species 
only as do actually occur together in nature ; so that each plate: 
represents a scene which is, at all events, not an impossible one. 
The species figured all belong to groups which are either pecu- 
liar to, or very characteristic of, the region whose zoology they 
illustrate ; and it is hoped that these pictures will of themselves 
serve to convey a notion of the varied types of the higher 
animals in their true geographical relations. The artist, Mr. J. 
B. Zwecker, to whose talent as a zoological draughtsman and 
great knowledge both of animal and vegetable forms we are 
indebted for this set of drawings, died a few weeks after he; 
