PREFACE. 



My late friend and colleague Osbert Salvin for many years made a special study 

 of the Order Tubinares, and together we collected specimens of Petrels from all 

 available sources, thus amassing a large and valuable series, which, with the rest of our 

 ornithological collection, numbering some 80,000 specimens, we finally presented 

 to the Natural History Museum. 



It was Salvia's intention on the completion of the " Tubinares " for the twenty-fifth 

 volume of the Catalogue of Birds in the British Museum, to write a fuller account 

 of the Petrels, and publish it as a Monograph, illustrated by coloured figures of each 

 species ; for that purpose we had some forty plates prepared by Mr. Keulemans, 

 but Salvia's untimely death, in June, 1898, put an end to this project. 



Although naturally anxious to carry out my friend's intention, a good deal of 

 extra work was now thrown upon my shoulders, and for some years I was too 

 much engaged with the " Biologia Centrali- Americana " to embark on any fresh 

 undertaking. As I hoped, however, at some future date to have more leisure, most 

 of the remaining plates (106 in all) were drawn and coloured under my supervision, so 

 as to be ready should opportunity occur. Having brought the unfinished volumes of the 

 " Rhopalocera " and the " Aves " for the " Biologia " to a conclusion, my attention 

 was again turned to the long intended Monograph, and with the able assistance of 

 Dr. R. Bowdler Sharpe, of the Natural History Museum, I no longer hesitated to make 

 a commencement. 



Professor Newton, one of our highest authorities on the Aves, writing to Sir 

 Walter Buller, said, " All Petrels are puzzling in almost every way," and he goes on 

 to say that though Salvin solved some of the puzzles, he doubted whether, in spite 

 of the trouble he had taken and all the opportunities at his command, he would 

 himself admit that he had completely disposed of all the difficulties of determination. 

 Unlike my late colleague, I had made no special study of the Order, and had it not 

 been for the promise of Dr. Sharpe's assistance, it would have been presumptuous in 

 me to have undertaken so difficult a task. 



I have endeavoured to carry out the work on the lines projected by Salvin. 

 Taking the Catalogue of Petrels as his guide, he proposed to omit the host of references 

 belonging to the various species, and to quote only such as belonged to their history 

 and distribution. 



rx 



