PREFACE. Vii. 
in the later editions of his work as well as by quite the majority 
of writers to the present day. Of the enormous mass of ornith- 
ological literature issued since Yarrell’s day, [have availed myself 
by gleaning where anything may be gleaned for my purpose, 
and if any of the works thus consulted are not included in the 
Bibliography it is because I have felt it necessary to restrict 
the list to the principal and most interesting. 
In conclusion I have to thank a number of past and present 
correspondents and friends who have obliged me with names 
or information for this book, and to beg their indulgence for 
not detailing more specifically the help they have given me. 
I must also add a word of thanks to Mr. H. F. Witherby for 
his kindly suggestions, and the interest he has shown in the 
publication of the work. 
H. Kirke Swany. 
38, Great Queen Street, Kingsway, 
London, W.C., 
December 12th, 1912. 
