PREFACE. IX 
obedience to some real or assumed priority existing one 
hundred or one hundred and fifty years ago. The real 
object of names is to give the student a certain knowledge, 
and if a bird has been known for a long period of time 
by an established name, it is evidently absurd to alter it at 
the caprice of the writer. 
These remarks do not apply with the same meaning to 
generic divisions, which must alter and become more 
numerous as the science progresses. I have therefore 
changed the nomenclature of Temminck for that which is in 
more general use in ornithology, though I have not hesitated 
to refrain from so doing when I have thought the circum- 
stances did not warrant such a step. 
The present edition will be published in five volumes, and 
I have again to thank those naturalists who have given me 
their kind assistance, among whom I may especially mention 
Mr. J. H. Gurney, Lord Lilford, Dr. Theodore Von Heuglin, 
the Rev. Canon Tristram, Colonel Irby, Mr. Savile Reid, 
Deputy Surgeon- General Stewart, Mr. Howard Saunders, 
Dr. Crowfoot, of Beccles, Professor Vanden-Nest, of the 
Zoological Society, Antwerp, Mr. Brooks, of Etawah, Leith 
Adams, M.B., and Mr. Bond. 
Colchester, Dec. list., 1874.. 
