PREFACE. 
viii 
the Supplement to the ‘Birds of Australia,’two “Allied” and two 
“Hairy” Hermits in the ‘Monograph of the Humming-Birds,’ and 
two “ Orange-breasted ” Trogons in the second edition of the Monograph. 
The list of “Errata et Corrigenda” proves that, with all one’s care, 
a good many mistakes will occur in a gigantic Index like the present. 
Many of these errors were uot discovered until the final sheets of the 
book were being checked, as it was impossible to put the whole of the 
work up in type at the same time, and in this way most of the mistakes 
were noted only when too late for correction. 
In conclusion, I can only hope that this ‘ Index,’ over which I have 
expended so much time, will be found to supply a real want, and will 
be of much service to the possessors of Gould’s splendid series of 
ornithological works. I have only once more to thank my assistant, 
Mr. Chubb, for the cheerful help which he has rendered me through¬ 
out the preparation of the work. 
Some little difficulty arose at first as to whose set of Gould’s works 
should be used as an authentic and complete copy. Messrs. Sotheran 
very kindly lent me a complete set of the Indices to the folio works, 
as far as they had got them, but they were unable to supply me with 
those of the ‘ Birds of Europe,’ the ‘ Birds of Australia,’ and some of the 
earlier Monographs. I therefore determined, in the case of these 
works, to depend upon the copies in the library of the Zoological 
Society of London. 
R. BOMLLEP SHARPE. 
Chiswick, Dec. 15, 1892. 
