PREFACE. 



ix has been a fortunate circumstance that for tlie preparatiuu of 

 the present Volume the cooperation of Mr. H. Saunders and 

 Mr. 0. iSalvin could be secured, who for many years past have 

 made the Birds of the families of Gulls and Petrels the special 

 subject of their respective studies. As also the collections formed 

 by these gentlemen have been incorporated with the series in 

 the British Museum, the latter possesses of both these groups 

 a collection unrivalled as to its intrinsic value, if not also as to 

 the number of species and specimens. 



According to the lists given, this Collection consists now of : — 



Species. 



Ganie 115 



Tubinares 109 



Among the Tubinares only, some of the species (15) are not 

 represented in the Collection. 



Beside the many friends and correspondents who have rendered 

 material assistance in the preparation of this Volume by the loan 

 or gift of specimens, and who "will be enumerated in the intro- 

 ductory remarks of the Authors, I have to refer specially to the 

 authorities of the United States National Museum and to the 

 Hon. AV. Rothschild, of whom the former sent important types 

 for comparison, whilst the latter placed the whole of his rich 

 collection at the disposal of Iho Authors. 



