iv PREFACE 



The Introduction fully explains the plan of the work, and the 

 lines which have been adopted in writing it, and books to which 

 the Author is specially indebted are either mentioned in the text, 

 or included in a special list at the end. It is both mentally and 

 physically impossible for one zoologist to know at first hand more 

 than a small part of his subject, and for this reason full quotations, 

 in preference to mere paraphrases, have been taken from the 

 writings of many distinguished specialists, the sources in such 

 cases being always indicated. 



Some of the coloured plates are by Specht, and the rest have 

 been drawn expressly for this book by Mr. William Kiihnert and 

 Mr. A. Fairfax Muckley. Some of the black-and-white plates, 

 and many of the text illustrations are also new, and the remainder 

 have been taken or re-drawn from acknowledged sources. Pro- 

 fessors Glinther and Poulton have kindly permitted some of their 

 illustrations to be copied, and Mr. R. A. Van Someren has been 

 so good as to place at my disposal a number of his interesting 

 photographs of birds and birds' nests. 



Special acknowledgment is also due to the authors and pub- 

 lishers of Das Tierreich, Die Schopfung der Tierwelt, and Das 

 Leben des Meeres, for their courteous permission to make use 

 of illustrations from those works. 



J. R. AINSWORTH DAVIS. 



ABERYSTWYTH, October /, 1902. 



