ADVERTISEMENT. 



When I presented my collection of Birds to the Zoological Society, Mr. 

 Gould kindly undertook to furnish me with descriptions of the new species and 

 names of those already known. This he has performed, but owing to the hurry, 

 consequent on his departure for Australia,— -an expedition from which the science 

 of Ornithology will derive such great advantages, — he was compelled to leave 

 some part of his manuscript so far incomplete, that without the possibility of 

 personal communication with him, I was left in doubt on some essential points. 

 Mr. George Robert Gray, the ornithological assistant in the Zoological depart- 

 ment of the British Museum, has in the most obliging manner undertaken to 

 obviate this difficulty, by furnishing me with information with respect to some 

 parts of the general arrangement, and likewise on that most intricate subject, — 

 the knowledge of what species have already been described, and the use of proper 

 generic terms. I shall endeavour in every part of the text to refer to Mr. G. R. 

 Gray's assistance, where I have used it. As some of Mr. Gould's descriptions 

 appeared to me brief, I have enlarged them, but have always endeavoured to retain 

 his specific character; so that, by this means, I trust I shall not throw any 

 obscurity on what he considers the essential character in each case ; but at the 

 same time, I hope, that these additional remarks may render the work more 

 complete. 



The accompanying illustrations, which are fifty in number, were taken from 

 sketches made by Mr. Gould himself, and executed on stone by Mrs. Gould, with 



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