PREFACE 



The advantages of local Faunas are too generally under- 

 stood and acknowledged to require any lengthened proof 

 or illustration. It may indeed be doubted whether the 

 study of the animals of particular tracts of country has 

 not contributed more than any other means to the ad- 

 vancement of zoological knowledge, especially as regards 

 those important branches, the geographical distribution 

 of animals, the influence of climate, of soil, and of other 

 local circumstances, in determining the range of species, 

 the changes of varieties, and the extent and periods of 



migration. 



It is true that in few instances only will the animal 

 productions of a single country furnish such a multitude 

 of forms in any particular group as may afford a satis- 

 factory illustration of the whole plan of zoological 

 arrangement. But even under our own ungenial and 

 changeful skies, few persons are aware to what extent 

 such domestic means of study exist, or how little we 

 need be indebted to foreign aid in acquiring the first 

 principles at least of zoological science. 



But allowing the necessity of foreign importations for 

 the acquisition of a knowledge even of certain principal 

 groups in each class of animals, there is another inipor- 



